0:00 Finding Kv (rpm per volt) rating of a hub motor. 0:10 set DC amps to 20a because im using my power supply and it has 24a max. 0:20 weakresponse is set to 7:none, so the controller wont add field weakening, 0:34 setting maxspeed to 1500 to allow it freedom to reach rated rpm at 60v 1:10 I raise ratios in speed limit to 1500 rpm to allow the motor to reach rated rpm. 2:00 60v and 1350 rpm is 22.5Kv. 22.5 rpm for each volt DC is max speed without field weakening. 2:50 weakresponse set to 0, which turns on field weakening. 3:06 notice the motor now goes up to the 1500 rpm limit set in maxspeed and ratios in speeds 3:25 setting maxspeed to 2000 to show what field weakening can do. 3:40 we also raised the speed limit in ratios in speed to around 1650 rpm. 4:19 it runs about 1665 rpm, limited by ratios in speeds. 5:01 setting DC amps to 5 amps to show it can limit field weakening depth 5:20 removing all limits in ratios in speed 6:14 raise DC amps to 10a to show it allows deeper field weakening 6:50 it can go all the way to 2000 rpm now, which is the maxspeed setting. 7:18 setting 3a DC limit to show it can limit rpm based on watts. 8:32 oops, this was supposed to be amp not rpm. Lol 9:42 rations in speeds must be used to limit depth of field weakening if boost function is used. 10:56 this is because I set rpm to 10. Lol 12:03 finally my fat thumbs got rpm back to 800 12:17 rpm limited to around 860 12:45 when boost is pressed, the maxspeed limits is overridden and only ratios in speed limits rpm.
Cool! Nice to learn a bit more about the setting up of the Fardrivers. I bought a 961200 recently but unfortunately could not adjust most of the settings due to "please use new BLE" being displayed. The seller sent me a new bluetooth and now I can set useful regen. The hub motor I use is a 13" 273 50H V4 with 24*9T windings. Would be interesting to get your opinion of the settings and the choice of winding configuration.
24 strand 9 turns? On a 13” wheel with a 273mm motor inside? That seems crazy. The 32 strand 5T 50H @ 96v is only 660 rpm before field weakening is needed. One thing to consider is the more turns there are in a slot, the fewer strands the winding will have, and the lower peak current it can handle before overheating. The 2T has 74 or 80 strands depending on the version. That would carry 3x the phase amps of a 24 strand winding. If that is the drive wheel for a Zamboni, you’re all set, but if that is a electric Grom you want to go 100 mph, thats the wrong winding. What is the vehicle and how fast do you want to go? The 961200 is for a 12 kw motor, thats a 273 70H with a 2T winding. A 273 50H is normally 8kw, but thats with 3T which has about 55 strands per winding bundle. A 24 strand 9T 50H with a tiny 13” wheel would give crazy torque with a 72360 controller. With a 19” OD tire it would only go 30 mph without field weakenong and maybe 60 with 100% field weakening. Do you have any videos showing what the fardriver app dashboard page shows during pull power acceleration and top speed run, along with a scroll through the settings? I have a video before this one showing 273 winding options 25H to 50 H, 2T to 5T. It might give some ideas. This video shows how to find your Kv, running with weak response set to 7. That can be done unloaded or on the road. For a 9T I think loaded and unloaded will be almost the same and at extremely low current.
@@imho7250 I am looking back at my info, when I got the motor this was in 2018 before the field weakening, high current controllers were around. So QS said this motor would be good for 1100 rpms @ 72V no load, I had this at 56mph for 72V and as I was thinking 92V later on that has it 75mph based on tyre circumference. This at the time was acceptable to me as I wanted strong acceleration in the 0 - 50 mph band. Our speed limit is 30mph so no real point in a 60 mph plus setup. I noticed when they suggested this winding it did not match the V3 8KW 13" 50H winding choices that were shared on their website, so I figured the V4 is wound differently than the V3's. A 1071RPM @ 72V V3 motor is wound 65*3T and listed as a 14.88kV motor. I was concerned with higher speed windings the need for a powerful controller pushing higher current would mean more heat and less efficiency at the sub 30mph speeds I would ride at most times and would it reduce range of the bike? When I took to the drag race track it got to 78mph in 160m, so the field weakening must have been doing along. This was on my previous 96850 Fardriver that died after a year and a half. Error 14. I put in the stand just a while ago after your message and set weak response to 7 and it shows 4528R on the no load speed . When I set to 0 I got 5534R no load speed. I then adjusted the ratios in speed so up to 3000RPMS it is 100% then taper off and the no load speed is 5721R. (note note 100% certain if these values are accurate, like is 5721R = 5721 RPMS? Maybe some setting needs adjusting to calibrate correctly? When setup it automatically chose 4 pole pairs, my old Fardriver was set to 16 pole pairs which is correct, would this affect the measured RPM value?) The bike certainly flies super fast to 55mph, I need to take to the track to see more as it's risky on our roads unless I find a good spot. I went from 96850 to 961200 so I could get the higher starting amps which helps alot. Front wheel lifts and skips on takeoff up the 50mph no problem. If I build a second bike will look at the next higher kV winding option, but might not make sense for the speeds I ride normally.
@@imho7250 Another video of it in the early days with a Kelly controller, Lithium phosphate batteries and 5000W motor. th-cam.com/video/BX27rcRwl-U/w-d-xo.html
@@moriwaki80 , ok, if that motor was very old it might not be 32 magnet 36 coil motor the ones today are, or maybe is Delta instead of Wye or vice versa, since that also affects Kv for any given wind, 1100 rpm @ 72v, seems more like the full tilt field weakening. Sometimes the manufacturer is ambiguous about it. You can see what the kv is if you ensure pole pairs are correct in settings (so it reports the correct rpm) and set weakresponse 7. I originally set my pole pairs wrong (40 instead of 20) and it wasn’t until I used gps and an online calculator that I noticed rpm was only showing 50% (because it was dividing poles passing per minute by 40 instead of 20 to get rpm). Your 96850 should have been plenty. My friend had a electric ninja with 273 50H and the 72890 (also 450a DC) and it did really well. 120 kph with field weakening off and 155 kph with field weakening. The danger to the controller for high Kv motors is that at 100% field weakening depth, the motor is trying to make 190, but field weakening has brought it down to 95v or so. But one wrong move by the controller, perhaps during regen, and voltage can go way past max voltage suddenly. Nucular controllers actually limit field weakening to the rpm that even if field weakening stoped, the motor voltage would not exceed the controller limits. My motor shown here is 22.5kv (14” tire) and does 70 kph on the road with field weakening off. And my controller is slightly over rated (i use 120a of the 190a max). And I only run 60v on my 72360 so my controller should never have an issue related to operating outside parameters. Would love to see videos of your FarDriver display during test runs to see how it compares to my friends bike in both settings and the rpm, amps, voltage data on the display during a full acceleration run.
@@moriwaki80 on the topic of choosing the ideal wind for a space bike, lets say you have a 961200 already, a 27s 100ah battery with 300a continuous and 600a peak, an E-Grom size motor with 13” wheels and 18” O.D. tires. Lets say you live in a free country which allows you to register it for the highway, and the speed of normal traffic is 70 mph and you want 105 mph in boost for passing or drag racing. For me, the ideal motor is the 273 70H (water cooled if possible). It’s the only one that can take 57 kw for 60 seconds or so. But if not possible then a 50H and the controller DC set to 300a normal and 450a boost. The ideal wind would be rated rpm for 70 mph (no field weakening), and then 50% field weakening depth for 105 mph. This would hopefully use about 100a at 70 mph and 400a at 105 mph. The problem with motorcycles is they have no room for batteries, so even if you had that huge 27s 100ah battery, thats only 1 hr cruise at 70 mph, so 70 miles range on the highway. If you take a slower road 35 mph you could go 140 miles. If you only want to drag race, it depends on the distance. 1/4 mile it would probably run out of rpm halfway through and need a higher kv winding. But you only want 0-60 mph then probably the wind that tops out at 60 with 50% depth of field weakening. But it also depends on the bike. For example we see E-bike guy with a 273 40H and 450a and now 600a battery and controller, 3.3T and it already will loop out from under anyone who twists the throttle fully. Yet some comment “If you go to 5T you will have more torque”. Lol. More than too much is not good. Lol There is also a misconception that more turns is more max torque but thats not true. Higher turn winding only increases Kt (torque per amp), but since the winding is fewer strands, it cant carry the same current. A 9T with 100 amp phase current would be about the same torque as a 3T with 300 amp phase current. And since the 3t winding has almost 3x the mm^2 as a 9T has: 55 strand 3t vs 24 strand 9T 55/24=2.3x strands and therefore 2.3c mm^2, so the 9T would technically make more peak torque before melting but only 20% more, not 300% more. The 9t would be much more efficient up to its rated (no field weakening) rpm, but by time its going the rated speed of a 3T, its using more power because field weakening is 100% so now the 50H magnet acts like a 25H and you need 200a for torque and 200a for field weakening. On top of all these theoretical numbers are the reality the aerodynamic drag at top speed. Will a motor with field weakening at 50% have enough torque to go the speed you want? And how many seconds can the windings/phase wires handle this current? In your case you already have a motor with a reference to what it does on your bike with you riding where and how you ride, so choosing a new wind is a bit easier. But I have seem people jump too far, from 3.3T to 2T when a 3T or 2.6T would have been optimal. My motor had no choice. Its 22.5 kv and i would say 1800w continuous (60v x 30a) and i can send 4x (120a) for short bursts. In my other video I show weakresponse 7 (no field weakening) and weak response 6 (field weakening on). And my motor balances at 40a @70 kph with no field weakening and with field weakening I had to end the test @ 80kph due to death wobble. If I modified the bike to be stable at 100 kph (62 mph) and used 72v then it would easily do that speed but probably need 100a instead of 40a to do the extra 30 kph. As it is, i leave field weakening off because it lets the motor run cooler when I give full acceleration to 70 kph.
@@dcktater7847 , what setup are you using? With WeakResponse 7 its not going to add field weakening, and as soon as back EMF matches the battery voltage, you will see “Weak” on the Fardriver app and DC amps will be pulled down below MaxLineCurr, even if all rpm limits are disabled. If you turn on field weakening from that limitless condition, on the road, DC amps will go to max and stay there. And if the bike is on a stand the motor will go so fast it can cause damage to any taters around. Lol
@@dcktater7847 , if you can make a simple screenrecording of the Fardriver app, do a slow scroll through settings top to bottom, then make a test run either on a stand or on the road, or can take a look, As long as you set pole pairs correctly, the digital rpm on the Fardriver app will be correct. It just counts magnets passing by but it has no way to detect how many magnets there are so you must put the correct value if you want rpm to work. Otherwise the Fardriver doesn’t use pole pairs to run. It’s only for the human so he can see rpm.
@@dcktater7847 If you are testing unloaded, make sure battery is at 50% charge, 72v for a 72v battery, because with no load the battery doesn’t sag hardly at all and the motor spins freely so it will run much faster before back EMF climbs to 84v, thats why we test at 72v if unloaded and trying to find the rated rpm. But if you can’t get it all the way down to normal voltage, you can still divide rpm/voltage based on what the Fardriver reports.
@@imho7250 i got the infamous "4 pole pair only" version. It spins to 9000 which is around 7k real life. This is qs 138 90h v3. However when i got the controller the fw was shut off and it was dismally slow on the road so maybe on load it works and it just doesnt work no load who knows...but for you it works no load too... But i also got a proper version of the new model which also doesnt react to shutting fw off. I measured 3.6k with a normal controller with the rpm meter on the shaft i'd just like to confirm it with the far driver this is a rickshaw motor and this far driver knows the 5 pole pair but even this seems to exceed the measured value no load...i mean i dont care about the qs it has a well known kv value i just gotta measure this rickshaw motor cause who knows what's inside these. It says 4000 rpm and 72volt on the motor but still i got it spinning to only 3.6k by the rpm meter...
Hi! First of all, thank you so much for the detailed content, it's really interesting! I would like to know if there's any way of limiting the maximum phase current the fardriver controller will provide at 100% throttle. (For instance, if I only want 800 phase amps, but I need the 600 DC amps from a 961200 controller, can I limit the phases to not provide more than 800A and therefore protect the motor from overheating?) Many thanks!
Yes, the Fardriver has individual DC and phase amp limits in settings. You can set DC amps to whatever the DC system can tolerate and set phase amps independent of that. However if you set DC amps to the maximum continuous current of the battery (instead of max peak current), and phase amps for max continuous phase amps, the performance will be very lackluster, but very safe for all components. So typically these limits will be set for peak current allowed, and then pulled back to within maximum continuous current. The Fardriver has a few features to automatically pull back current after the maximum acceleration: MaXSpeed (rpm). This is the most basic setting every controller has, and you would typically set this limit such that the amps get pulled down to within maximum continuous. Ratios in speed. This allows you to allow different percentage of max phase current depending on the rpm range. The benefit of this over MaxSpeed rpm limit is you can allow 800a phase amps up to a certain rpm, then pull it back to 25% (200a) above a certain rpm. This allows your top speed to vary depending on going uphill/against the wind or downhill with a tailwind. The other protection feature is Boost. This is basically like having gear 4, but it has some additional protection. If you wire up the boost function, this allows you to set more conservative values for speed 3. (400 DC and 600 phase, with rpm limit that pulls it back to 200a DC for example), and then set 600a DC and 800-1200a phase, and then you set the time limit to the seconds that your components can handle that. 5-130 seconds, and then also it has a cooldown timer. Boost overrides MaxSpeed rpm limit and uses only ratios in speeds as its limit. This allows you to fully utilize the peak current for the peak time its safe to use it. If you have the motor temperature sensor and it’s selected in the fardriver, that will shut off the controller when the motor reaches 160c. But this feature is best used for monitoring motor temps and setting current and time limits (if boost is used) to levels that won’t let the motor overheat.
@@imho7250 Thank you very much for the thorough response, I'm actually trying to find what would be the best cost to benefit controller for my setup, so I'm thinking about testing with maybe a 961800 and then limiting currents to simulate a 96850 or a 961200. Then I can check what delivers the desired performance and get just that (and sell the controller I used to test). But anyway, keep up the excellent work, I'm subscribed now!
@@wagnerbrochini3892 , what is your motor? Whats the mm^2 of the phase wires? Thats always a clue at what they can tolerate. Once you get up to the big boys Fardrivers they also offer racing versions which have a higher e-rpm capability. But this will only be useful on a mid-drive. I have a 2kw motor so i got a Fardriver 72360 (190 DC amps) but set DC to only 60a when I had my old battery and then 120 with my new battery. Then later added Boost and set DC to 80a and boost DC to 120a. This controller is really for a 3kw motor so it left me some overhead. Generally Fardriver controller can delete 4x rated power at it’s highest battery voltage. For example a 72360 is said to be for 2-3 kw motors. (2 kw for 48v and 3kw for 72v), but the real peak output is: 48v x 190a = 9120 watts 60v x 190a = 11400 watts 72v x 190a = 13680 watts So this ensures you can send at least 4x rated power for acceleration, which I find is the realistic limit. We see some sending 10x rated power but this only gives you that power for about 1 second, then the windings start glowing red. Lol If your 96v battery can handle 600a without sagging more than 0.5v/cell, the 961200 will give 57600 watts, good for any motor rated at 12kw continuous. If your 96v batter can handle 800a without sagging more than 0.5v/cell, then 961800 will give 76800 watts, good for any motor rated at 16 kw continuous. If you can afford the higher current model and run it at a lower current that should give a margin of safety for the controller and also allows you to actually test 5x, 6x rated power for a few seconds to see if it helps. I did a few tests at 180a but couldn’t really tell much difference over the 120a, but the motor got very hot very fast. Even at 120a (4x rated power), the first acceleration feels strong and then the wires heat up and looses some off the line torque.
@@imho7250 Since you are interested in digging into the rabbit hole, let's go: I'm planning on using an inexpensive mid drive, preferably water cooled, like the QS138-C, the QS180 (which would require a CNC milled casing to become watercooled) or even the MG138-F. The thing is that, from all of those, only the QS180 is 4 pole pairs, the others are 5 (which greatly limits my maximum RPM). My plan is to push them to 12000rpm on a very high 2-stage reduction for monstruous wheel torque. Anything besides the MG138-F (which requires 1000A on the phases to produce about 75Nm) would have to be rewound for double the Kv (and double the required current) as I don't plan to use any field weakening whatsoever. Also phase wires could be anything desired, as those are directly connected to the windings that are going to be changed; actually my plan is to use the ends of the windings as the phase cables and having the controller really close to the motor. Still rotor pole pairs are the limiting factor here. Since you've mentioned erpms, I read somewhere that regular fardrivers are 36000erpm capable and track versions are 48000erpm, but that would have to be confirmed. That puts a 961800 track right about where I would need to be with the QS180 (48000erpm and 4 pole pairs is 12000rpm maximum). I would need something like a motor from a Tesla (3 pole pairs) to reach that maximum rpm with regular fardrivers, but that is unviable cost wise. !! If you know about any decent options with 3 pole pairs it would greatly help me !! On the battery front, I'll be using very high rate of discharge LFP cells in a 32S pack, matching any of the 96 series of the Fardriver lineup. The sag is calculated so that the pack voltage goes to about 92 to 93V when WOT (wide open throttle), maximum power figures would be about 55kW (600A DC), 73kW (800A DC) and 100kW (1100A DC, limited by maximum pack output with the 961800 track). Final gear reduction is about 7.6:1 and I would need the motor to output about 150Nm, that is really QS180 territory with a BIG if... lol
@@wagnerbrochini3892 , I think e-RPM (which is calculated differently by different manufacturers) is 48,000 normal and 60,000 track. There is a guy demo 12,000 rpm normal and 15,000 rpm track, on a 4 pole pair setting. A 4 pole pair motor will have a higher rpm than a 5 pole pair motor, if the limit is 48,000 pole pairs per minute. The 4 pole pair would be 12000 and the 5 pole pair would be 9600 rpm. But this shouldn’t be a decision factor because you still can change final drive ratio to whatever you want. Its good that you are using 2-stage reduction because that will allow regen to work reasonably well. I believe going over 5:1 reduction becomes a proper when back-driven and doesn’t work well. Something like the way a torsen limited slip differential works. LFP is generally not well suited to high C discharge, but if you have enough cells and they are as high drain as LFP comes in, that would be ok. My rule of thumb of 0.5v/cell sag is for Li-ion, but for LFP which has an SOC curve more like a lead acid battery, i would say as long at it doesn’t sag below 3.2v/cell at the controller under max discharge, its ok. That would mean on your 32s, minimum voltage at max current at the Fardriver should be 102v. But this is only super critical if you use field weakening or your Kv needs 100v to reach the rpm you geared everything for. Field weakening is great for anything that needs a momentary top speed 25%-50% faster than the cruise speed (before field weakening is needed). But if you are building something that you only want max speed all the time, then gearing it for no field weakening will be best, at a cost of low end torque. Without field weakening you would still have a maximum cruise speed limited by the maximum continuous rating of your battery and motor, and a slightly higher maximum speed because all amps are going to pushing you and none used to reduce magnet strength. The good thing is whatever you do with a mid-drive, if you don’t like the overall drive-ability, you can change the final drive ratio and use more or less field weakening. This is the Achilles Heel of Hub motors because you can’t rewind it easily each time you want a different ratio. Lol I don’t know if specifically going for 3-pole pairs will help. Sure it can run faster rpm but im not sure for the size and weight it gives more torque than 4,5, 6 pole pairs. QS could easily make a 3 pole pair motor, but they don’t. Normally it’s 5, 6, 7 pole pairs. The main thing is its interior magnets not surface mounted like a Surron motor. Its quite an engineering challenge to make an EV from scratch because you also need the aerodynamic drag curve for the vehicle. If its a motorcycle then it’s super challenging because the rider can change that drastically, unlike in a car the driver has little effect on top speed, which is inversely problematic to the weight of his testicles. Lol Ill check out your channel to see if you have anything on this project yet.
Hey bro i wanted to ask what could be the reason for throttle cutoff. I have qs120 2kw and 58V 12AH battery having 120A max continuous current Weak response set to 7 so no weakning. When i instantly push the throttle it cutsoff the throttle . Amps no problem as it not going above 45 50. Bms is also not a problem rates for 200A So i know the controller is cutting off the throttle and after few seconds comes back on
The only 12ah battery with 120a continuous is LiPo cells. So i would like to see more about the pack. If its a 14s3p P42a pack its not really 120a continuous, its more like 90a continuous and thats a bit high. If you have a Bluetooth BMS you can see whats going on in the battery during acceleration to see if any brick is sagging under load. I only use Bluetooth bms because the basic BMS doesn’t tell you anything thats going on. If you don’t have Bluetooth BMS, then probably your Fardriver low voltage protection is not set correctly. Open the Fardriver app and make sure battery voltage in -Parameters is set to 52, then scroll down to -Protect section and set LowVoltageProtect to 42v. If lowVoltageRestore doesn’t automatically set a few volts higher then set it to 44v. Let me know if this helped.
@@imho7250 the pack consists of 14s4p sony vtc 6 Yes its a bluetooth bms tdt6056 but my bluetooth modules faulty i can only connect pc but still it beeps when error occurs when theres low voltage protect on and thats not the case right now
Hey bro!can u send me ur friends(with the qs273) field weikening settings?also can i apply field weikening after 1000 rpm?i dont want to loose accelaration.
Each Fardriver must be tuned individually for the vehicle, battery, motor, rider, ambient temperature. Once you turn field weakening on (WeakResponse:0), the only thing you need to do is make sure that doesn’t destroy the battery, the wiring, or the motor. This is done by setting: 1. Max!ineCurr 2. MaxPhaseCurr The current limits are set to whatever the weakest link in the system can tolerate for 60 seconds to a few minutes (depending how aggressive you want it. But this will off course burn something up if not reined in by RPM (or using the boost feature with timers). The two ways to pull current back after acceleration are: 1. MaxSpeed (bypassed in boost mode) 2. Ratios in speeds: pulls back phase current to a percentage of MaxPhaseCurr or BoostPhaseCurr. Many DIY builds for themselves are on the ragged edge and they just mentally track the thermal load, but if its for someone else all the settings need to automatically pull back current to maximum continuous current after acceleration up to a certain speed. Boost is a motor protection feature that allows you to set normal current and rpm limits so that even an idiot cant burn your motor, while allowing “turn and burn” amps and rpm, but for limited seconds (5-130 seconds I think). Then there is a cooldown timer. Typically you would use this for passing or drag racing. If you make a screenrecording of your settings and dashboard during acceleration and top speed, and then tell me what you want it to do differently, O can help you. Make sure the video is not for kids and not a short so I can comment on it. My friend’s 273 is 3T 50H on 17” wheel pushing a full size electric ninja in 30c temperature, his motor has temperature sensor and he monitors it and allows cooldown between runs so his settings might not be for you. I will post that video link below for reference but his settings are only for his bike and his riding environment and riding style. It’s not the “master fardriver settings” because no such thing.
Here is that video: th-cam.com/video/Rp6lOYMWASI/w-d-xo.htmlsi=9CqlV4Ysxs9tjpFu Be aware there is no rpm limit set so it will burn the motor up with these settings if not monitoring the engine temp and releasing throttle before something overheats. He does have the real QS 273 with temperature sensor and the Fardriver will shut down at 160c motor temp but thats way too high and something else could be smoking already. Lol
Oh i dont have boost.my gear 3 is the high amps gear so i have to pull dc back from ratios in speed.but what rpm i start to down the %? After 1000 till i go to 2000 to 1% is ok? (My motor is qs 273 10kw 60h with 25m² cables.i can go a bit higher than ur friend)
@@apostolospetridis6038 , does your motor have the temperature sensor and is that selected in your Fardriver? The temperature is what determines all the settings if you want the Fardriver to protect the motor. If you will be the one protected the motor then you don’t need any rpm limit, you could set the DC amps to 40kw (depending on your battery voltage), which is 4x the 10kw rating of your motor. Your motor kw is 10 kw but what is the Kv? My friend’s bike was 3T so with a 21s battery sagging to 80v he can do 120 kph without field weakening. I don’t know how fast 1000 rpm is on your bike because I don’t know your rear tire size. If you want max safe continues speed you need to set ratios in speeds such that it tapers down to max continuous phase current once you enter field weakening, but this will make your bike top speed much lower. If you can make a screenrecording of your fardriver when doing acceleration and top speed on the road, I can see whats going on.
@@meteor_vr9144 you need to find the weakest link in your system. That could be the battery cells, the BMS, the power cables or the motor and its phase wires. When slowly upgrading components, the weakest link will shift such as if you upgrade the battery but not motor or vice versa. We can generally ignore phase amps and look only at Max Line Current. And there are two ways to limit line current. Peak line current is set with Max line current and can be set from 200%-400% of the motor maximum rated continuous power, after you convert that from watts to amps. The second limit which is especially important if you enable field weakening is the rpm limit, which is MaxSpeed setting in mode 3 or if you use boost its ratios in speed. This rpm limit is what pulls back the amps from 400% to 100% once you reach max continuous cruise speed. If you enable boost you can use more than 100% continuous oower because there is a time limit setting. So you can let it use 400% power for 10 seconds, 300% power for 30 seconds, 200% power for 60 seconds, as an example. But this is determined by testing while monitoring motor winding temperature. If you don’t have temperature sensor in the motor then you have to be more conservative with settings and feel the motor after each test run. As far as the battery, while in field weakening, you should not be above maximum amps the cells can deliver with stable voltage. This means for Li-ion batteries, maximum current is that which causes a 0.5v/cell sag. So if you have a 20s pack, and start at 80v, with max amps the sag should not go below 70v. If you have a weak battery and want the most you can set MaxLineCurr higher than what causes a 0.5v/cell drop but you must use maxspeed or ratios in speed to pull that down to max current or it will be unstable and go into a low voltage death spiral as feild weakening tries to come for a weak battery set at too high a max amps, Hopefully that helps. Ask any additional questions for clarity.
0:00 Finding Kv (rpm per volt) rating of a hub motor.
0:10 set DC amps to 20a because im using my power supply and it has 24a max.
0:20 weakresponse is set to 7:none, so the controller wont add field weakening,
0:34 setting maxspeed to 1500 to allow it freedom to reach rated rpm at 60v
1:10 I raise ratios in speed limit to 1500 rpm to allow the motor to reach rated rpm.
2:00 60v and 1350 rpm is 22.5Kv. 22.5 rpm for each volt DC is max speed without field weakening.
2:50 weakresponse set to 0, which turns on field weakening.
3:06 notice the motor now goes up to the 1500 rpm limit set in maxspeed and ratios in speeds
3:25 setting maxspeed to 2000 to show what field weakening can do.
3:40 we also raised the speed limit in ratios in speed to around 1650 rpm.
4:19 it runs about 1665 rpm, limited by ratios in speeds.
5:01 setting DC amps to 5 amps to show it can limit field weakening depth
5:20 removing all limits in ratios in speed
6:14 raise DC amps to 10a to show it allows deeper field weakening
6:50 it can go all the way to 2000 rpm now, which is the maxspeed setting.
7:18 setting 3a DC limit to show it can limit rpm based on watts.
8:32 oops, this was supposed to be amp not rpm. Lol
9:42 rations in speeds must be used to limit depth of field weakening if boost function is used.
10:56 this is because I set rpm to 10. Lol
12:03 finally my fat thumbs got rpm back to 800
12:17 rpm limited to around 860
12:45 when boost is pressed, the maxspeed limits is overridden and only ratios in speed limits rpm.
Cool! Nice to learn a bit more about the setting up of the Fardrivers. I bought a 961200 recently but unfortunately could not adjust most of the settings due to "please use new BLE" being displayed. The seller sent me a new bluetooth and now I can set useful regen. The hub motor I use is a 13" 273 50H V4 with 24*9T windings. Would be interesting to get your opinion of the settings and the choice of winding configuration.
24 strand 9 turns? On a 13” wheel with a 273mm motor inside? That seems crazy. The 32 strand 5T 50H @ 96v is only 660 rpm before field weakening is needed.
One thing to consider is the more turns there are in a slot, the fewer strands the winding will have, and the lower peak current it can handle before overheating. The 2T has 74 or 80 strands depending on the version. That would carry 3x the phase amps of a 24 strand winding.
If that is the drive wheel for a Zamboni, you’re all set, but if that is a electric Grom you want to go 100 mph, thats the wrong winding.
What is the vehicle and how fast do you want to go? The 961200 is for a 12 kw motor, thats a 273 70H with a 2T winding. A 273 50H is normally 8kw, but thats with 3T which has about 55 strands per winding bundle.
A 24 strand 9T 50H with a tiny 13” wheel would give crazy torque with a 72360 controller. With a 19” OD tire it would only go 30 mph without field weakenong and maybe 60 with 100% field weakening.
Do you have any videos showing what the fardriver app dashboard page shows during pull power acceleration and top speed run, along with a scroll through the settings?
I have a video before this one showing 273 winding options 25H to 50 H, 2T to 5T. It might give some ideas. This video shows how to find your Kv, running with weak response set to 7. That can be done unloaded or on the road. For a 9T I think loaded and unloaded will be almost the same and at extremely low current.
@@imho7250 I am looking back at my info, when I got the motor this was in 2018 before the field weakening, high current controllers were around.
So QS said this motor would be good for 1100 rpms @ 72V no load, I had this at 56mph for 72V and as I was thinking 92V later on that has it 75mph based on tyre circumference. This at the time was acceptable to me as I wanted strong acceleration in the 0 - 50 mph band. Our speed limit is 30mph so no real point in a 60 mph plus setup.
I noticed when they suggested this winding it did not match the V3 8KW 13" 50H winding choices that were shared on their website, so I figured the V4 is wound differently than the V3's. A 1071RPM @ 72V V3 motor is wound 65*3T and listed as a 14.88kV motor.
I was concerned with higher speed windings the need for a powerful controller pushing higher current would mean more heat and less efficiency at the sub 30mph speeds I would ride at most times and would it reduce range of the bike?
When I took to the drag race track it got to 78mph in 160m, so the field weakening must have been doing along. This was on my previous 96850 Fardriver that died after a year and a half. Error 14.
I put in the stand just a while ago after your message and set weak response to 7 and it shows 4528R on the no load speed . When I set to 0 I got 5534R no load speed. I then adjusted the ratios in speed so up to 3000RPMS it is 100% then taper off and the no load speed is 5721R. (note note 100% certain if these values are accurate, like is 5721R = 5721 RPMS? Maybe some setting needs adjusting to calibrate correctly? When setup it automatically chose 4 pole pairs, my old Fardriver was set to 16 pole pairs which is correct, would this affect the measured RPM value?)
The bike certainly flies super fast to 55mph, I need to take to the track to see more as it's risky on our roads unless I find a good spot.
I went from 96850 to 961200 so I could get the higher starting amps which helps alot. Front wheel lifts and skips on takeoff up the 50mph no problem. If I build a second bike will look at the next higher kV winding option, but might not make sense for the speeds I ride normally.
@@imho7250 Another video of it in the early days with a Kelly controller, Lithium phosphate batteries and 5000W motor.
th-cam.com/video/BX27rcRwl-U/w-d-xo.html
@@moriwaki80 , ok, if that motor was very old it might not be 32 magnet 36 coil motor the ones today are, or maybe is Delta instead of Wye or vice versa, since that also affects Kv for any given wind,
1100 rpm @ 72v, seems more like the full tilt field weakening. Sometimes the manufacturer is ambiguous about it.
You can see what the kv is if you ensure pole pairs are correct in settings (so it reports the correct rpm) and set weakresponse 7. I originally set my pole pairs wrong (40 instead of 20) and it wasn’t until I used gps and an online calculator that I noticed rpm was only showing 50% (because it was dividing poles passing per minute by 40 instead of 20 to get rpm).
Your 96850 should have been plenty. My friend had a electric ninja with 273 50H and the 72890 (also 450a DC) and it did really well. 120 kph with field weakening off and 155 kph with field weakening.
The danger to the controller for high Kv motors is that at 100% field weakening depth, the motor is trying to make 190, but field weakening has brought it down to 95v or so. But one wrong move by the controller, perhaps during regen, and voltage can go way past max voltage suddenly. Nucular controllers actually limit field weakening to the rpm that even if field weakening stoped, the motor voltage would not exceed the controller limits.
My motor shown here is 22.5kv (14” tire) and does 70 kph on the road with field weakening off. And my controller is slightly over rated (i use 120a of the 190a max). And I only run 60v on my 72360 so my controller should never have an issue related to operating outside parameters.
Would love to see videos of your FarDriver display during test runs to see how it compares to my friends bike in both settings and the rpm, amps, voltage data on the display during a full acceleration run.
@@moriwaki80 on the topic of choosing the ideal wind for a space bike, lets say you have a 961200 already, a 27s 100ah battery with 300a continuous and 600a peak, an E-Grom size motor with 13” wheels and 18” O.D. tires.
Lets say you live in a free country which allows you to register it for the highway, and the speed of normal traffic is 70 mph and you want 105 mph in boost for passing or drag racing.
For me, the ideal motor is the 273 70H (water cooled if possible). It’s the only one that can take 57 kw for 60 seconds or so. But if not possible then a 50H and the controller DC set to 300a normal and 450a boost.
The ideal wind would be rated rpm for 70 mph (no field weakening), and then 50% field weakening depth for 105 mph. This would hopefully use about 100a at 70 mph and 400a at 105 mph.
The problem with motorcycles is they have no room for batteries, so even if you had that huge 27s 100ah battery, thats only 1 hr cruise at 70 mph, so 70 miles range on the highway. If you take a slower road 35 mph you could go 140 miles.
If you only want to drag race, it depends on the distance. 1/4 mile it would probably run out of rpm halfway through and need a higher kv winding. But you only want 0-60 mph then probably the wind that tops out at 60 with 50% depth of field weakening.
But it also depends on the bike. For example we see E-bike guy with a 273 40H and 450a and now 600a battery and controller, 3.3T and it already will loop out from under anyone who twists the throttle fully. Yet some comment “If you go to 5T you will have more torque”. Lol. More than too much is not good. Lol
There is also a misconception that more turns is more max torque but thats not true. Higher turn winding only increases Kt (torque per amp), but since the winding is fewer strands, it cant carry the same current. A 9T with 100 amp phase current would be about the same torque as a 3T with 300 amp phase current. And since the 3t winding has almost 3x the mm^2 as a 9T has:
55 strand 3t vs 24 strand 9T
55/24=2.3x strands and therefore 2.3c mm^2, so the 9T would technically make more peak torque before melting but only 20% more, not 300% more.
The 9t would be much more efficient up to its rated (no field weakening) rpm, but by time its going the rated speed of a 3T, its using more power because field weakening is 100% so now the 50H magnet acts like a 25H and you need 200a for torque and 200a for field weakening.
On top of all these theoretical numbers are the reality the aerodynamic drag at top speed. Will a motor with field weakening at 50% have enough torque to go the speed you want? And how many seconds can the windings/phase wires handle this current?
In your case you already have a motor with a reference to what it does on your bike with you riding where and how you ride, so choosing a new wind is a bit easier. But I have seem people jump too far, from 3.3T to 2T when a 3T or 2.6T would have been optimal.
My motor had no choice. Its 22.5 kv and i would say 1800w continuous (60v x 30a) and i can send 4x (120a) for short bursts. In my other video I show weakresponse 7 (no field weakening) and weak response 6 (field weakening on). And my motor balances at 40a @70 kph with no field weakening and with field weakening I had to end the test @ 80kph due to death wobble.
If I modified the bike to be stable at 100 kph (62 mph) and used 72v then it would easily do that speed but probably need 100a instead of 40a to do the extra 30 kph. As it is, i leave field weakening off because it lets the motor run cooler when I give full acceleration to 70 kph.
This doesnt work on mine. I set "7 none" and still weakens like crazy. Maybe i gotta restort to the good ol' handheld rpm meter 😢
@@dcktater7847 , what setup are you using? With WeakResponse 7 its not going to add field weakening, and as soon as back EMF matches the battery voltage, you will see “Weak” on the Fardriver app and DC amps will be pulled down below MaxLineCurr, even if all rpm limits are disabled.
If you turn on field weakening from that limitless condition, on the road, DC amps will go to max and stay there. And if the bike is on a stand the motor will go so fast it can cause damage to any taters around. Lol
@@dcktater7847 , if you can make a simple screenrecording of the Fardriver app, do a slow scroll through settings top to bottom, then make a test run either on a stand or on the road, or can take a look,
As long as you set pole pairs correctly, the digital rpm on the Fardriver app will be correct. It just counts magnets passing by but it has no way to detect how many magnets there are so you must put the correct value if you want rpm to work. Otherwise the Fardriver doesn’t use pole pairs to run. It’s only for the human so he can see rpm.
@@dcktater7847 If you are testing unloaded, make sure battery is at 50% charge, 72v for a 72v battery, because with no load the battery doesn’t sag hardly at all and the motor spins freely so it will run much faster before back EMF climbs to 84v, thats why we test at 72v if unloaded and trying to find the rated rpm.
But if you can’t get it all the way down to normal voltage, you can still divide rpm/voltage based on what the Fardriver reports.
@@imho7250 i got the infamous "4 pole pair only" version. It spins to 9000 which is around 7k real life. This is qs 138 90h v3. However when i got the controller the fw was shut off and it was dismally slow on the road so maybe on load it works and it just doesnt work no load who knows...but for you it works no load too...
But i also got a proper version of the new model which also doesnt react to shutting fw off. I measured 3.6k with a normal controller with the rpm meter on the shaft i'd just like to confirm it with the far driver this is a rickshaw motor and this far driver knows the 5 pole pair but even this seems to exceed the measured value no load...i mean i dont care about the qs it has a well known kv value i just gotta measure this rickshaw motor cause who knows what's inside these. It says 4000 rpm and 72volt on the motor but still i got it spinning to only 3.6k by the rpm meter...
@@dcktater7847 , yes those 4 pole pair only if
Hi! First of all, thank you so much for the detailed content, it's really interesting! I would like to know if there's any way of limiting the maximum phase current the fardriver controller will provide at 100% throttle. (For instance, if I only want 800 phase amps, but I need the 600 DC amps from a 961200 controller, can I limit the phases to not provide more than 800A and therefore protect the motor from overheating?) Many thanks!
Yes, the Fardriver has individual DC and phase amp limits in settings. You can set DC amps to whatever the DC system can tolerate and set phase amps independent of that.
However if you set DC amps to the maximum continuous current of the battery (instead of max peak current), and phase amps for max continuous phase amps, the performance will be very lackluster, but very safe for all components.
So typically these limits will be set for peak current allowed, and then pulled back to within maximum continuous current. The Fardriver has a few features to automatically pull back current after the maximum acceleration:
MaXSpeed (rpm). This is the most basic setting every controller has, and you would typically set this limit such that the amps get pulled down to within maximum continuous.
Ratios in speed. This allows you to allow different percentage of max phase current depending on the rpm range. The benefit of this over MaxSpeed rpm limit is you can allow 800a phase amps up to a certain rpm, then pull it back to 25% (200a) above a certain rpm. This allows your top speed to vary depending on going uphill/against the wind or downhill with a tailwind.
The other protection feature is Boost. This is basically like having gear 4, but it has some additional protection. If you wire up the boost function, this allows you to set more conservative values for speed 3. (400 DC and 600 phase, with rpm limit that pulls it back to 200a DC for example), and then set 600a DC and 800-1200a phase, and then you set the time limit to the seconds that your components can handle that. 5-130 seconds, and then also it has a cooldown timer. Boost overrides MaxSpeed rpm limit and uses only ratios in speeds as its limit. This allows you to fully utilize the peak current for the peak time its safe to use it.
If you have the motor temperature sensor and it’s selected in the fardriver, that will shut off the controller when the motor reaches 160c. But this feature is best used for monitoring motor temps and setting current and time limits (if boost is used) to levels that won’t let the motor overheat.
@@imho7250 Thank you very much for the thorough response, I'm actually trying to find what would be the best cost to benefit controller for my setup, so I'm thinking about testing with maybe a 961800 and then limiting currents to simulate a 96850 or a 961200. Then I can check what delivers the desired performance and get just that (and sell the controller I used to test). But anyway, keep up the excellent work, I'm subscribed now!
@@wagnerbrochini3892 , what is your motor? Whats the mm^2 of the phase wires? Thats always a clue at what they can tolerate.
Once you get up to the big boys Fardrivers they also offer racing versions which have a higher e-rpm capability. But this will only be useful on a mid-drive.
I have a 2kw motor so i got a Fardriver 72360 (190 DC amps) but set DC to only 60a when I had my old battery and then 120 with my new battery. Then later added Boost and set DC to 80a and boost DC to 120a. This controller is really for a 3kw motor so it left me some overhead.
Generally Fardriver controller can delete 4x rated power at it’s highest battery voltage. For example a 72360 is said to be for 2-3 kw motors. (2 kw for 48v and 3kw for 72v), but the real peak output is:
48v x 190a = 9120 watts
60v x 190a = 11400 watts
72v x 190a = 13680 watts
So this ensures you can send at least 4x rated power for acceleration, which I find is the realistic limit. We see some sending 10x rated power but this only gives you that power for about 1 second, then the windings start glowing red. Lol
If your 96v battery can handle 600a without sagging more than 0.5v/cell, the 961200 will give 57600 watts, good for any motor rated at 12kw continuous.
If your 96v batter can handle 800a without sagging more than 0.5v/cell, then 961800 will give 76800 watts, good for any motor rated at 16 kw continuous.
If you can afford the higher current model and run it at a lower current that should give a margin of safety for the controller and also allows you to actually test 5x, 6x rated power for a few seconds to see if it helps.
I did a few tests at 180a but couldn’t really tell much difference over the 120a, but the motor got very hot very fast. Even at 120a (4x rated power), the first acceleration feels strong and then the wires heat up and looses some off the line torque.
@@imho7250 Since you are interested in digging into the rabbit hole, let's go:
I'm planning on using an inexpensive mid drive, preferably water cooled, like the QS138-C, the QS180 (which would require a CNC milled casing to become watercooled) or even the MG138-F. The thing is that, from all of those, only the QS180 is 4 pole pairs, the others are 5 (which greatly limits my maximum RPM). My plan is to push them to 12000rpm on a very high 2-stage reduction for monstruous wheel torque.
Anything besides the MG138-F (which requires 1000A on the phases to produce about 75Nm) would have to be rewound for double the Kv (and double the required current) as I don't plan to use any field weakening whatsoever. Also phase wires could be anything desired, as those are directly connected to the windings that are going to be changed; actually my plan is to use the ends of the windings as the phase cables and having the controller really close to the motor. Still rotor pole pairs are the limiting factor here.
Since you've mentioned erpms, I read somewhere that regular fardrivers are 36000erpm capable and track versions are 48000erpm, but that would have to be confirmed. That puts a 961800 track right about where I would need to be with the QS180 (48000erpm and 4 pole pairs is 12000rpm maximum). I would need something like a motor from a Tesla (3 pole pairs) to reach that maximum rpm with regular fardrivers, but that is unviable cost wise. !! If you know about any decent options with 3 pole pairs it would greatly help me !!
On the battery front, I'll be using very high rate of discharge LFP cells in a 32S pack, matching any of the 96 series of the Fardriver lineup. The sag is calculated so that the pack voltage goes to about 92 to 93V when WOT (wide open throttle), maximum power figures would be about 55kW (600A DC), 73kW (800A DC) and 100kW (1100A DC, limited by maximum pack output with the 961800 track).
Final gear reduction is about 7.6:1 and I would need the motor to output about 150Nm, that is really QS180 territory with a BIG if... lol
@@wagnerbrochini3892 , I think e-RPM (which is calculated differently by different manufacturers) is 48,000 normal and 60,000 track. There is a guy demo 12,000 rpm normal and 15,000 rpm track, on a 4 pole pair setting.
A 4 pole pair motor will have a higher rpm than a 5 pole pair motor, if the limit is 48,000 pole pairs per minute. The 4 pole pair would be 12000 and the 5 pole pair would be 9600 rpm. But this shouldn’t be a decision factor because you still can change final drive ratio to whatever you want.
Its good that you are using 2-stage reduction because that will allow regen to work reasonably well. I believe going over 5:1 reduction becomes a proper when back-driven and doesn’t work well. Something like the way a torsen limited slip differential works.
LFP is generally not well suited to high C discharge, but if you have enough cells and they are as high drain as LFP comes in, that would be ok. My rule of thumb of 0.5v/cell sag is for Li-ion, but for LFP which has an SOC curve more like a lead acid battery, i would say as long at it doesn’t sag below 3.2v/cell at the controller under max discharge, its ok. That would mean on your 32s, minimum voltage at max current at the Fardriver should be 102v. But this is only super critical if you use field weakening or your Kv needs 100v to reach the rpm you geared everything for.
Field weakening is great for anything that needs a momentary top speed 25%-50% faster than the cruise speed (before field weakening is needed). But if you are building something that you only want max speed all the time, then gearing it for no field weakening will be best, at a cost of low end torque.
Without field weakening you would still have a maximum cruise speed limited by the maximum continuous rating of your battery and motor, and a slightly higher maximum speed because all amps are going to pushing you and none used to reduce magnet strength.
The good thing is whatever you do with a mid-drive, if you don’t like the overall drive-ability, you can change the final drive ratio and use more or less field weakening. This is the Achilles Heel of Hub motors because you can’t rewind it easily each time you want a different ratio. Lol
I don’t know if specifically going for 3-pole pairs will help. Sure it can run faster rpm but im not sure for the size and weight it gives more torque than 4,5, 6 pole pairs. QS could easily make a 3 pole pair motor, but they don’t. Normally it’s 5, 6, 7 pole pairs. The main thing is its interior magnets not surface mounted like a Surron motor.
Its quite an engineering challenge to make an EV from scratch because you also need the aerodynamic drag curve for the vehicle. If its a motorcycle then it’s super challenging because the rider can change that drastically, unlike in a car the driver has little effect on top speed, which is inversely problematic to the weight of his testicles. Lol
Ill check out your channel to see if you have anything on this project yet.
Hey bro i wanted to ask what could be the reason for throttle cutoff.
I have qs120 2kw and 58V 12AH battery having 120A max continuous current
Weak response set to 7 so no weakning.
When i instantly push the throttle it cutsoff the throttle . Amps no problem as it not going above 45 50.
Bms is also not a problem rates for 200A
So i know the controller is cutting off the throttle and after few seconds comes back on
The only 12ah battery with 120a continuous is LiPo cells. So i would like to see more about the pack. If its a 14s3p P42a pack its not really 120a continuous, its more like 90a continuous and thats a bit high.
If you have a Bluetooth BMS you can see whats going on in the battery during acceleration to see if any brick is sagging under load. I only use Bluetooth bms because the basic BMS doesn’t tell you anything thats going on.
If you don’t have Bluetooth BMS, then probably your Fardriver low voltage protection is not set correctly.
Open the Fardriver app and make sure battery voltage in -Parameters is set to 52, then scroll down to -Protect section and set LowVoltageProtect to 42v. If lowVoltageRestore doesn’t automatically set a few volts higher then set it to 44v.
Let me know if this helped.
@@imho7250 the pack consists of 14s4p sony vtc 6
Yes its a bluetooth bms tdt6056 but my bluetooth modules faulty i can only connect pc but still it beeps when error occurs when theres low voltage protect on and thats not the case right now
@@imho7250 i have screen recording i can send you
@@hassanshakeel1462 , ok, did you check the Fardriver settings I mentioned in the previous comment?
@@imho7250 the low voltage protect 30V and over voltage is 60V
In my recording i havent seen the voltage go below 42V
Hey bro!can u send me ur friends(with the qs273) field weikening settings?also can i apply field weikening after 1000 rpm?i dont want to loose accelaration.
Each Fardriver must be tuned individually for the vehicle, battery, motor, rider, ambient temperature.
Once you turn field weakening on (WeakResponse:0), the only thing you need to do is make sure that doesn’t destroy the battery, the wiring, or the motor. This is done by setting:
1. Max!ineCurr
2. MaxPhaseCurr
The current limits are set to whatever the weakest link in the system can tolerate for 60 seconds to a few minutes (depending how aggressive you want it.
But this will off course burn something up if not reined in by RPM (or using the boost feature with timers). The two ways to pull current back after acceleration are:
1. MaxSpeed (bypassed in boost mode)
2. Ratios in speeds: pulls back phase current to a percentage of MaxPhaseCurr or BoostPhaseCurr.
Many DIY builds for themselves are on the ragged edge and they just mentally track the thermal load, but if its for someone else all the settings need to automatically pull back current to maximum continuous current after acceleration up to a certain speed.
Boost is a motor protection feature that allows you to set normal current and rpm limits so that even an idiot cant burn your motor, while allowing “turn and burn” amps and rpm, but for limited seconds (5-130 seconds I think). Then there is a cooldown timer. Typically you would use this for passing or drag racing.
If you make a screenrecording of your settings and dashboard during acceleration and top speed, and then tell me what you want it to do differently, O can help you. Make sure the video is not for kids and not a short so I can comment on it.
My friend’s 273 is 3T 50H on 17” wheel pushing a full size electric ninja in 30c temperature, his motor has temperature sensor and he monitors it and allows cooldown between runs so his settings might not be for you. I will post that video link below for reference but his settings are only for his bike and his riding environment and riding style. It’s not the “master fardriver settings” because no such thing.
Here is that video: th-cam.com/video/Rp6lOYMWASI/w-d-xo.htmlsi=9CqlV4Ysxs9tjpFu
Be aware there is no rpm limit set so it will burn the motor up with these settings if not monitoring the engine temp and releasing throttle before something overheats. He does have the real QS 273 with temperature sensor and the Fardriver will shut down at 160c motor temp but thats way too high and something else could be smoking already. Lol
Oh i dont have boost.my gear 3 is the high amps gear so i have to pull dc back from ratios in speed.but what rpm i start to down the %? After 1000 till i go to 2000 to 1% is ok? (My motor is qs 273 10kw 60h with 25m² cables.i can go a bit higher than ur friend)
@@apostolospetridis6038 , does your motor have the temperature sensor and is that selected in your Fardriver? The temperature is what determines all the settings if you want the Fardriver to protect the motor.
If you will be the one protected the motor then you don’t need any rpm limit, you could set the DC amps to 40kw (depending on your battery voltage), which is 4x the 10kw rating of your motor.
Your motor kw is 10 kw but what is the Kv? My friend’s bike was 3T so with a 21s battery sagging to 80v he can do 120 kph without field weakening.
I don’t know how fast 1000 rpm is on your bike because I don’t know your rear tire size.
If you want max safe continues speed you need to set ratios in speeds such that it tapers down to max continuous phase current once you enter field weakening, but this will make your bike top speed much lower.
If you can make a screenrecording of your fardriver when doing acceleration and top speed on the road, I can see whats going on.
@@imho7250 i have temp sensor! I dont know kv.ok i will try record in accelaration when im on road.i ll let you know soon!!!
so with field weakening, should I use the battery specs for line and phase current? or do you have to set it lower like you did?
@@meteor_vr9144 you need to find the weakest link in your system. That could be the battery cells, the BMS, the power cables or the motor and its phase wires. When slowly upgrading components, the weakest link will shift such as if you upgrade the battery but not motor or vice versa.
We can generally ignore phase amps and look only at Max Line Current. And there are two ways to limit line current.
Peak line current is set with Max line current and can be set from 200%-400% of the motor maximum rated continuous power, after you convert that from watts to amps.
The second limit which is especially important if you enable field weakening is the rpm limit, which is MaxSpeed setting in mode 3 or if you use boost its ratios in speed. This rpm limit is what pulls back the amps from 400% to 100% once you reach max continuous cruise speed.
If you enable boost you can use more than 100% continuous oower because there is a time limit setting. So you can let it use 400% power for 10 seconds, 300% power for 30 seconds, 200% power for 60 seconds, as an example. But this is determined by testing while monitoring motor winding temperature. If you don’t have temperature sensor in the motor then you have to be more conservative with settings and feel the motor after each test run.
As far as the battery, while in field weakening, you should not be above maximum amps the cells can deliver with stable voltage. This means for Li-ion batteries, maximum current is that which causes a 0.5v/cell sag. So if you have a 20s pack, and start at 80v, with max amps the sag should not go below 70v.
If you have a weak battery and want the most you can set MaxLineCurr higher than what causes a 0.5v/cell drop but you must use maxspeed or ratios in speed to pull that down to max current or it will be unstable and go into a low voltage death spiral as feild weakening tries to come for a weak battery set at too high a max amps,
Hopefully that helps. Ask any additional questions for clarity.