What a cool demonstration. You also proved the assumption that batteries in simple parallel with load taken from the end batteries....draws slightly more amps from those end batteries. For ebike purposes with multiple parallel cells. could be significant unbalancing eventually Thanks for your effort.
Nice, I Found that if you add a very large amount of cooling to one of those converters and keep it cool you can run it very hard reliably! I have a 1200w version, I am using it to charge my ebike at just under 1200w. I've got it putting out 15 amps at 90v and have done about 20 cycles so far with no problems. I built mine into a rectangular box with a delta fan on each end in push pull config. They are 30w fans, so quite powerful. I probably don't need that much cooling, but I wanted them for future proofing. If I had a bigger supply I could probably get it to push through more power.
cool videos! how do i choose the resistance value to add in series? i need to pass 150A of current and ideally drop less than 1V. is a very small resistance still work okay with power supply? or do they need to be in the ~100mOhm range to work?
You got each unit up to 10 amps at 50V? For how long? I only have one unit so far, but I just ordered a few more to try exactly what you have here. I have the first one at 50 degrees C and climbing after 30 minutes at 4.75 amps. It will burn in less than 2 hours in my test. I'm testing at 52V. The heat sink fan is working. Did you have extra cooling in play? I believe my unit is the same as yours. I bought the one labelled 1800W output, but so far it can do nowhere near that label. Its heat runs away from me at just 300W. If the next two are the same, I'll need three units just to pull 15 amps.
Hi, curious how you arrived at 0.1 - 10Watt resistors? If I wanted to force load balancing of 2 X 58V 28A power supplies, how would you recommend I do that? I want to power a double pill 65V RF Amp I am building.
Good Stuff .Was curious if this could be done. Im intending to purchase an icom ic705, a 10w output radio. I would like to use it in the shack, as a portable and also occasionally in the car. (or using my old ic718)The car would have an innefficient antenna on lower Ham bands. perhaps 1% eff on 80m and about 5% on 40m bands. So an amp would be required for decent performance.1kw would do me I think Also considering a alternator upgrade to help with running the higher loads.
hi, i purchased the same module, but 12v FAN is not working through that port, does it start when module starts or it's a temperature controlled ? i tested and waited until it reached 62"C but fan did't started...... if it directly starts then which iC or component is responsible for constant 12v regulation ? or if there is temperature control sensor which turn on the fan then where is it!!! plz help me, i will be waiting for your reply .
i could use some help rf man. ive been trying to step up 5 48volt 30 amp 1000 watt ebike batteries to run at 64 volts using 3 1200 watt step up boosters in parallel. i tried your resistor way and had results when using a 12 volt power source, but once i had all the boosters adjusted to 64 volts, when i hooked them up to the battery packs, nothing is happening, it looks like no power is getting through even though i know the 5 packs in parallel have 46 volts of power in them still. i dont understand where i am going wrong
hey RF Man what if you wanted to get 20A from each of the 4 converters to get 80A total, what size resistors would I need? Edit: I have the 1800W versions which claim 40A
@@taruix603x5 Honestly though I have tested them. They can handle around 40A INPUT not output...so do your math P=VI and account for about 10% ineffeciency...
I would use this DC-DC converter with a maximum of 50% of the rated output current capacity, otherwise the operating point will be very inefficient and the ripple noise will increase even more.
Do you know if a 12-volt 100-amp car battery will work with this step up converter? It looks like these converters are mostly rated at 30-40 amp input. Let me know. Thanks.
I think a 70AH 100 amp battery with a voltage drop of 0.8 volts should be possible. You just have to make sure that you use a battery that has the lowest possible internal resistance. I therefore recommend using an additional battery with AGM technology. A high-current diode should be used between the starter battery and the AGM additional battery. Alternatively, you could take four AGM batteries and connect them in series so that you have 55 volts, and operate the LDMOS amplifier over it, which relieves the load on the starter battery and the alternator. Four 20AH AGM lead batteries for uninterruptible power supplies would be sufficient. It is important to connect a relay including high-current fuse between the starter battery and the DC-DC converter! The AGM batteries also reduce the ripple voltage. Best 73
He doesn't respond to his videos it would seem. But to answer your question those power supplies he has there which are rated to 90 amps total, are probably being maxed out when he pushes the converter to put out total of 20 amps at 50v = 1000w. You get an efficiency loss from the converters as well 20% roughly (dependant on voltage gap). but 12v x 90 amps is 1080 watts. So in fact he's probably stressing those 12v power supplies when you consider the conversion efficiency loss.
Hi great video building small ldmos amp only 300w have a 30 amp 12v supply trying to use stuff I have ,would 1 1500w work or would you run 2 and split the load as need 50v at 15 amp
One 1500 watt amplifier will work with a 50 volt 30 amp power supply. You can use 2 power supplies in parallel but you need to address the load sharing. I have a video on this topic on my channel. Thanks
It would run cooler. Power dissipation would be the same for a resister of the same value. If you are talking about running one 20 watt resistor instead of the four 10 watt ones, that won't work. Not only are the 4 resistors dissipating more than 20 watts, the resistors are not wired in parallel. They are each connected to the output of one of the boost converters.
You are pushing out 10A @ 50V. That makes about 42A @ 12V on the Input, without efficiency loss. At 85% that would be even 49 Amps, so way over spec. You can easily measure input current with your setup, so go ahead and do that. It’s specified for a input or output current of 30Amps max, depending on which is higher. Because your input voltageis so low, your input current goes through the roof. What you could do instead is connecting the power supplies in Series, so you get 36Volts of input. That makes 1080 Watts @ 36V / 30 amps. Efficiency of 85% makes about 920Watts Output. So you will get 18 Amps max per UNIT, 72Amps total output @ 50V without exceeding max current. whereas at 12Volts of input you will get only 6 Amps per Unit, 24 Amps total. So go ahead and connect your psu‘s in serial. Look out, maybe the housing is grounded to negative, then you have to make sure, that the housings are not touching, or you will short the psu‘s. For the total output of 20A @ 50V, you will need every PSU to be able to produce 65 Amps @ 12V. Are they rated for that current?
you appear to know your stuff . i am looking to use three 12volt 18amp hour batteries in a series to get 36volts 18amp hours....i want to use this battery setup for powering an ebike kit. the kit requires 48volts max of 20 amps.....would you use step-up converters in parallel like this to achieve that ? i would rather not buy 18650 battery packs (500 dollars) and i want to save as much battery weight as possible..each of these 12 volt batteries weigh 13 pounds each. you have any suggestions ?
@@bobamericana3099 Are you aware that you can get a 40a version of these that runs 1800 watts? I have one and they are only $25, & then you dont need to do any load sharing.
@@bobamericana3099 Sure...here you go: www.ebay.com/itm/1800W-40A-DC-DC-Boost-Converter-Step-Up-Power-Supply-Module-Constant-US/253660804697?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649
@Transmitters 'R' Us I would suggest using a 500F supercap bank. The current peaks are not good for the voltage regulators of the alternators. In addition, less voltage fluctuations result in better linearity.
What a cool demonstration. You also proved the assumption that batteries in simple parallel with load taken from the end batteries....draws slightly more amps from those end batteries. For ebike purposes with multiple parallel cells. could be significant unbalancing eventually Thanks for your effort.
Nice, I Found that if you add a very large amount of cooling to one of those converters and keep it cool you can run it very hard reliably! I have a 1200w version, I am using it to charge my ebike at just under 1200w. I've got it putting out 15 amps at 90v and have done about 20 cycles so far with no problems. I built mine into a rectangular box with a delta fan on each end in push pull config. They are 30w fans, so quite powerful. I probably don't need that much cooling, but I wanted them for future proofing. If I had a bigger supply I could probably get it to push through more power.
What is your input voltage?
@@Pricesminis I'm using a 48v rectifier. I have also used it a 12v 200 amps server psu running it at slightly lower power output charging at 12 amps.
@@jcreedy20 do you have a link for the rectifier
Nice 💪💪💪
Can these be ran in series to get 120 dc 7.6 amps?
cool videos! how do i choose the resistance value to add in series? i need to pass 150A of current and ideally drop less than 1V. is a very small resistance still work okay with power supply? or do they need to be in the ~100mOhm range to work?
Great! Thanks for sharing.
You got each unit up to 10 amps at 50V? For how long?
I only have one unit so far, but I just ordered a few more to try exactly what you have here. I have the first one at 50 degrees C and climbing after 30 minutes at 4.75 amps. It will burn in less than 2 hours in my test. I'm testing at 52V. The heat sink fan is working. Did you have extra cooling in play?
I believe my unit is the same as yours. I bought the one labelled 1800W output, but so far it can do nowhere near that label. Its heat runs away from me at just 300W. If the next two are the same, I'll need three units just to pull 15 amps.
Hi, curious how you arrived at 0.1 - 10Watt resistors? If I wanted to force load balancing of 2 X 58V 28A power supplies, how would you recommend I do that? I want to power a double pill 65V RF Amp I am building.
Hey RF Man,
Id like to get a price on a 50v 2 transistor LDMOS base set up from you.
Do you have any contact info?
577
Good Stuff .Was curious if this could be done. Im intending to purchase an icom ic705, a 10w output radio. I would like to use it in the shack, as a portable and also occasionally in the car. (or using my old ic718)The car would have an innefficient antenna on lower Ham bands. perhaps 1% eff on 80m and about 5% on 40m bands. So an amp would be required for decent performance.1kw would do me I think Also considering a alternator upgrade to help with running the higher loads.
hi, i purchased the same module, but 12v FAN is not working through that port, does it start when module starts or it's a temperature controlled ? i tested and waited until it reached 62"C but fan did't started...... if it directly starts then which iC or component is responsible for constant 12v regulation ? or if there is temperature control sensor which turn on the fan then where is it!!! plz help me, i will be waiting for your reply .
i could use some help rf man. ive been trying to step up 5 48volt 30 amp 1000 watt ebike batteries to run at 64 volts using 3 1200 watt step up boosters in parallel. i tried your resistor way and had results when using a 12 volt power source, but once i had all the boosters adjusted to 64 volts, when i hooked them up to the battery packs, nothing is happening, it looks like no power is getting through even though i know the 5 packs in parallel have 46 volts of power in them still. i dont understand where i am going wrong
Please demonstrate how to increase out put current with this booster
hey RF Man what if you wanted to get 20A from each of the 4 converters to get 80A total, what size resistors would I need? Edit: I have the 1800W versions which claim 40A
Where did you buy that? Do you have the link?
@@taruix603x5 Honestly though I have tested them. They can handle around 40A INPUT not output...so do your math P=VI and account for about 10% ineffeciency...
I would use this DC-DC converter with a maximum of 50% of the rated output current capacity, otherwise the operating point will be very inefficient and the ripple noise will increase even more.
hi, do you have a video on parallel connecting those 12v server PSU's? thanks ;-]
Will this work the same way on 12v switcher power supply
Do you know if a 12-volt 100-amp car battery will work with this step up converter? It looks like these converters are mostly rated at 30-40 amp input. Let me know. Thanks.
I think a 70AH 100 amp battery with a voltage drop of 0.8 volts should be possible. You just have to make sure that you use a battery that has the lowest possible internal resistance. I therefore recommend using an additional battery with AGM technology. A high-current diode should be used between the starter battery and the AGM additional battery.
Alternatively, you could take four AGM batteries and connect them in series so that you have 55 volts, and operate the LDMOS amplifier over it, which relieves the load on the starter battery and the alternator.
Four 20AH AGM lead batteries for uninterruptible power supplies would be sufficient.
It is important to connect a relay including high-current fuse between the starter battery and the DC-DC converter!
The AGM batteries also reduce the ripple voltage. Best 73
Is this for a single or 2 LDMOS set up?
Yes, that is correct.
What if 0.1 ohms 20watts resistor is used
how much current does it draws from the source power supply at that setup?
He doesn't respond to his videos it would seem. But to answer your question those power supplies he has there which are rated to 90 amps total, are probably being maxed out when he pushes the converter to put out total of 20 amps at 50v = 1000w. You get an efficiency loss from the converters as well 20% roughly (dependant on voltage gap). but 12v x 90 amps is 1080 watts. So in fact he's probably stressing those 12v power supplies when you consider the conversion efficiency loss.
@@jcreedy20 i have seen these to be 93-97% efficient, both on my bench and others
Why are you doing it this way? Is there an advantage? Why not just roll your own properly size boost converter?
HOW DO I CONTACT YOU?
Hi great video building small ldmos amp only 300w have a 30 amp 12v supply trying to use stuff I have ,would 1 1500w work or would you run 2 and split the load as need 50v at 15 amp
One 1500 watt amplifier will work with a 50 volt 30 amp power supply. You can use 2 power supplies in parallel but you need to address the load sharing. I have a video on this topic on my channel. Thanks
Thanks
What if 20watt resistor is used instead of 0.1 ohms 10watts
It would run cooler. Power dissipation would be the same for a resister of the same value. If you are talking about running one 20 watt resistor instead of the four 10 watt ones, that won't work. Not only are the 4 resistors dissipating more than 20 watts, the resistors are not wired in parallel. They are each connected to the output of one of the boost converters.
You are pushing out 10A @ 50V. That makes about 42A @ 12V on the Input, without efficiency loss. At 85% that would be even 49 Amps, so way over spec. You can easily measure input current with your setup, so go ahead and do that. It’s specified for a input or output current of 30Amps max, depending on which is higher. Because your input voltageis so low, your input current goes through the roof.
What you could do instead is connecting the power supplies in Series, so you get 36Volts of input.
That makes 1080 Watts @ 36V / 30 amps. Efficiency of 85% makes about 920Watts Output.
So you will get 18 Amps max per UNIT, 72Amps total output @ 50V without exceeding max current. whereas at 12Volts of input you will get only 6 Amps per Unit, 24 Amps total.
So go ahead and connect your psu‘s in serial. Look out, maybe the housing is grounded to negative, then you have to make sure, that the housings are not touching, or you will short the psu‘s.
For the total output of 20A @ 50V, you will need every PSU to be able to produce 65 Amps @ 12V. Are they rated for that current?
you appear to know your stuff . i am looking to use three 12volt 18amp hour batteries in a series to get 36volts 18amp hours....i want to use this battery setup for powering an ebike kit. the kit requires 48volts max of 20 amps.....would you use step-up converters in parallel like this to achieve that ? i would rather not buy 18650 battery packs (500 dollars) and i want to save as much battery weight as possible..each of these 12 volt batteries weigh 13 pounds each.
you have any suggestions ?
@@bobamericana3099 Are you aware that you can get a 40a version of these that runs 1800 watts? I have one and they are only $25, & then you dont need to do any load sharing.
@@englishrupe01 you have a link ?
@@bobamericana3099 Sure...here you go: www.ebay.com/itm/1800W-40A-DC-DC-Boost-Converter-Step-Up-Power-Supply-Module-Constant-US/253660804697?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649
@@englishrupe01 "Input current: 40A, Output current: 22A"
What's the point?
Operating the Amp from your mobile.
Is this a alternate solution to using 2 or three altenators or for mobile units used on base station
@Transmitters 'R' Us I would suggest using a 500F supercap bank. The current peaks are not good for the voltage regulators of the alternators. In addition, less voltage fluctuations result in better linearity.
Is there any way to regulate current from a car 24v alternator on amps down to 40a?
Mine blew up the third time Mike eat it down
I meant to say mine blew up when I keyed it down the third time