Don't know if you noticed, but the three versus four resistors on the two middle channels was just because there were five positions for all channels, but the middle ones had two resistors round the corner instead of one. So they all had five resistors. I have one of these chargers branded under a different name like LaCrosse or something. It's 3V connector burnt out! I soldered the wires directly to the PCB but one has since detached. If you ever picked it up while it was charging cells then the connector made a "50Hz" sensation as it turned! The two thermal sensors for four cells is a bit tacky, and on mine the buttons were totally unresponsive due to poor software monitoring of the buttons. You could always repurpose the remnants of the charger by converting it into a Chinese grade deathtrap, but paralleling all the cell positions and feeding them directly from the mains via a phat capacitor and rectifier.
I couldn't find a video of you taking one to bits? I'd be very grateful if you could shine some light on the circuitry. One of the four channels on mine, thinks there's a full cell inserted, while in fact there's none. The 3 volts that's present at the terminals (open circuited) somehow gets pulled down via a lower resistance to ground (while I measure this resistance it steadily rises) I think. But after desoldering all the pain in the ass smd transistors and diodes it's still present :(
I've been using the BL700 for a couple of years and find it very reliable. It does fail to charge cells with a low voltage so I start them off in another charger when necessary. I also found the 500mA charge rate better than 200mA for detecting the cell full status. The refresh mode is excellent.
Mine's still in regular use after 8 and a half years, I paid $28 for it. I've never had any trouble reading the display myself but the buttons do require a firm press. Having this plugged in on the bench saves me mucking around with multimeter probes to check the voltage of alkaline cells too (just insert for a second or so to read voltage). Yes on occasion have found that a cell charged a bit too long on the 200mAh setting so if I'm not going to be around to keep an eye on it near the end then I'll just use the 500mAh setting. It's not perfect but for the price at the time it's been a fantastic investment and it hasn't killed the Eneloops that I bought at the same time either - also still in regular use. I'd like a fancy new one but it's not really justified yet...
Very interesting video. I have the Youshiko YC4000 copy. My screen has started to disappear. Do you know if its possible to replace the screen or would cleaning the zebra stripe fix the issue ?
I have been very happy with my 8 cell Powerex charger. I had to repair it after first use due to one of my cells spewing up all over it, but it's been fine since. Certainly my favourite charger.
Hi all,well I must add that you should allways use the correct power supply that came with it.You can't really put the charger down as its user error,it says 3v on it,I don't understand all the fuss,The designer didn't design it for use with other voltages,and modification's, power supply's etc,I do think they should add over current/voltage protection but like I said they come with a power supply that's correct. Ime not having a go,I just think posts like these can put people off buying a very good product.😉
Don't suppose, while you had it in bits Julian, that you noticed any control or adjustment for the LCD contrast? Mine is awful, especially on colder days. Haven't opened it up yet, so you could save me the effort.
Love this vid! I've broken a couple of these units, some the BC-900 version (same as the 700 but with more charging current options on the higher end) as well as trashing one of my BL-700s. Also I've trashed batteries in it, presumably because the thermistor which is located rather stupidly in my opinion has not picked-up on a very hot battery. My current BL-700 works okay, although sometimes I notice one of the batteries is still charging after 3 days and very hot: not good! For £30-45 depending on the model it shouldn't be hard to put a mini buck converter in there should it? And upgrade it with a nice little colour oled? And fix the charge detection design flaws?
Ah yes, the old 12 volt in the wrong socket deal! I recently learned that this can happen to computers as well. I was trying to change an old Toughbook over to Linux the other day, the unit came without a CD/DVD drive, so I wanted to use an USB external DVD drive that I have for just such purposes. IT was not being seen by the toughbook, so I thought, I will simply plug it into my new Dell Laptop (well a year old) so I plugged her in, again the led on the DVD drive did light but no recognition. So I looked at the drive, and saw a point where you could plug in a 5 volt power supply, with that in mind, I grabbed a wire with a plug on the end, and shoved her in, while still plugged into my DELL. There was a slight wiff of smoke from my DELL, and the screen went dead, the fan stopped and she died. I quickly unplugged the USB drive, and pressed the power button, I was happy to see the circle containing the DELL logo on the screen as my machine returned to life. It appears all that was damaged was the data pins on that USB circuit. The laptop still has the USB 3 port that works fine, and I can power stuff from the other 2 ports but they are no longer available to transfer data. Guess I can live with that, I am going to get a bottle of red testers pla paint and color all my 12 volt plugs red to keep me aware of this danger
I do have the Technoline BC450 which is a smaller model with less charge current and it runs off 12 Volts! Not sure why they went for the lower voltage on higher charge currents, probably to reduce losses but I'm not sure...
The ' Youshiko YC4000' looks like a good replacement for that one. You'll get slightly higher charge rate options, 12v input and as a bonus a USB 5v output. I recently bought the Opus BC-3100 v2.1 and don't have any issues it so far... other than it has a fan, and makes some noise... but I suppose it does need to cool itself when charging 3xAA at 1A each and discharging a li-ion cell at 1A to check it's capacity :D
It looks like one of the traces from the power jack snakes down the left hand side of the charger and goes to one of the blowen 3 pin devices. Hopefully that saved the micro from damage.
Just recieved a Nitecore Digicharger D4, looks really promising so far. It has a really nice display and 12/230V. Do you think there is notable loss going through the 12 to 3V? Since you are running of solar..
its going to need 3v sooner or later as the rough charging voltage for the batteries, so either lose it externally or internnally to the charger, but dc-dc converters are pretty efficient
I thoroughly enjoy your uploads, I'm waiting with baited breath to see how you're proceeding with your arduino quadcopter. On a totally different note (hello Julian), are you in a position to advise on the pros and cons of low cost hot air/soldering stations by any chance?
On your earlier video showing this charger, I thought "why not put a cheap 12v->3v switcher inside and wire it in so it's powered off your 12v supply like everything else?" I'm viewing these a year and more after you made them but it might be something to consider in the future.
That's odd, I have the Technoline BC-700 and it has EXACTLY the same specs. Are the ones in the UK BL-700? Who knows... I will never understand the product naming of some companies...
The MAHA charger has a seperate thermistor for each cell. I have had one fail by a static discharge into a battery terminal, but it only zapped a cmos analog switch chip that was easy to replace. While I was in there, I added a 10uf ceramic cap across the small electrolytic that bypasses the supply bus, where it feeds the four switching charge regulators. It was way too small to handle the ripple current while charging 4 cells at max charge current..
aha heres an idea for a project/video! If most of us looked in our junk boxes we'd find an old charger case of some type or other. These things are sort of generic and there are lots of cheap "building blocks" on ebay, maybe a little recycling too . . What do you reckon Julian, Clive ?? could be fun, maybe some sparkes too ! ! !
It's probably best that you label your connections to prevent problems like that in the future at least the device didn't fail because of quality issues. I have the MAHA charger that also will not charge certain low batteries and I also believe it has damaged some good batteries. I wouldn't pay another £50.00 to replace it. It has lasted a few years though.
I've had the PowerEx C9000 WizardOne now for a few years. On mine, soon as you put a battery in, press ENTER (to select 'charge' from the menu on the left). The next screen that flashes up on mine is "Charge Rate" that I can select from 100ma to 2000ma (at 100ma intervals) using the up/down arrow keys. Then ENTER again to select.
Ah, I see. That is true, but, what do you charge in your Powerex mostly? Eneloops, right? And I've been told that a good rule of thumb is charge your cells with half the rate of their capacity. So in that way, the Powerex default is good for Eneloops. Did you know it was/is(?) also sold under the Memorex brand?
I think it might be time to permanently mount one of your many step-down DC-DC converter PCBs onto the back of that Technoline charger, so that particular mistake can never ever happen again. Cheers!!
Those chargers have absolutely no regulation on the pcb. They are so critical to the power supply voltage, that putting 12v in there will dump way more than the displyed current into the cells, so much it way overheats the switching mosfets. Your Powerex has a regulator near the power jack. It's wastefull, but just keep the input volt as low as the charger will operate when you're on battery/solar power. Ie. if it runs at 9v, as most of those regulators will, then thst's less energy wasted wa
Hey, it's meant to be powered from low voltage DC. MOVs would be completely useless because they can only clamp above a few tens of volts, but by that time everything on the board would already be fried. I agree that a diode to protect from reverse polarity could be good, but at least the plug has the standard configuration.
it would be great if you'd increase the bitrate of your video or the encoding scheme... somewhat blurry and blocky at places. Makes it hard to distinguish small detail :)
Doesn't have anything to do with my resolution. I have 100Mb/s internet connection and 27" full HD monitor and I did check my video resolution options when I noticed that. It's about the bitrate of the video combined with some encoding artifacts that make some details mushy. :/Darren Nash
Mtaalas I'm pretty sure julian is recording with a nexus 4, so tbh, I think he's doing a pretty good job with the quality. Also, the magnifying glass can't help the image quality in the closeups.
I can't understand this - I have multiple items that use the same plug and they are all different voltages. Why would anyone assume anything is just 12v without checking what the device wants? In this case the 3V is stated in large clear white letters - not like it's tiny indentations that you have to hold the light at just the right angle to read or anything. No-one was set up for failure here. I perfectly understand wanting to use alternate plugs or power sources but if you aren't going to use the supplied adaptor it's absolutely the users responsibility to check.
"totally my fault i put 12 volts into it...." now i have a new favourite charger ? WTF ... if you put gasoline in your "favourite diesel car" would you suddenly decide on a new favourite car after it breaks??? LOL just seems odd to me but who cares, it is not important..... by the way, i think i know why the resistors are missing [ i could make up some sarcastic comment right now but i won't LOL] i think it has to do with socket 1and4 being able to be programed differently on the bc-1000
Don't know if you noticed, but the three versus four resistors on the two middle channels was just because there were five positions for all channels, but the middle ones had two resistors round the corner instead of one. So they all had five resistors. I have one of these chargers branded under a different name like LaCrosse or something. It's 3V connector burnt out! I soldered the wires directly to the PCB but one has since detached. If you ever picked it up while it was charging cells then the connector made a "50Hz" sensation as it turned! The two thermal sensors for four cells is a bit tacky, and on mine the buttons were totally unresponsive due to poor software monitoring of the buttons. You could always repurpose the remnants of the charger by converting it into a Chinese grade deathtrap, but paralleling all the cell positions and feeding them directly from the mains via a phat capacitor and rectifier.
I couldn't find a video of you taking one to bits? I'd be very grateful if you could shine some light on the circuitry. One of the four channels on mine, thinks there's a full cell inserted, while in fact there's none. The 3 volts that's present at the terminals (open circuited) somehow gets pulled down via a lower resistance to ground (while I measure this resistance it steadily rises) I think. But after desoldering all the pain in the ass smd transistors and diodes it's still present :(
I've been using the BL700 for a couple of years and find it very reliable. It does fail to charge cells with a low voltage so I start them off in another charger when necessary. I also found the 500mA charge rate better than 200mA for detecting the cell full status.
The refresh mode is excellent.
Mine's still in regular use after 8 and a half years, I paid $28 for it. I've never had any trouble reading the display myself but the buttons do require a firm press. Having this plugged in on the bench saves me mucking around with multimeter probes to check the voltage of alkaline cells too (just insert for a second or so to read voltage). Yes on occasion have found that a cell charged a bit too long on the 200mAh setting so if I'm not going to be around to keep an eye on it near the end then I'll just use the 500mAh setting. It's not perfect but for the price at the time it's been a fantastic investment and it hasn't killed the Eneloops that I bought at the same time either - also still in regular use. I'd like a fancy new one but it's not really justified yet...
Very interesting video. I have the Youshiko YC4000 copy. My screen has started to disappear. Do you know if its possible to replace the screen or would cleaning the zebra stripe fix the issue ?
I have been very happy with my 8 cell Powerex charger. I had to repair it after first use due to one of my cells spewing up all over it, but it's been fine since. Certainly my favourite charger.
Hi all,well I must add that you should allways use the correct power supply that came with it.You can't really put the charger down as its user error,it says 3v on it,I don't understand all the fuss,The designer didn't design it for use with other voltages,and modification's, power supply's etc,I do think they should add over current/voltage protection but like I said they come with a power supply that's correct. Ime not having a go,I just think posts like these can put people off buying a very good product.😉
Don't suppose, while you had it in bits Julian, that you noticed any control or adjustment for the LCD contrast?
Mine is awful, especially on colder days. Haven't opened it up yet, so you could save me the effort.
Love this vid! I've broken a couple of these units, some the BC-900 version (same as the 700 but with more charging current options on the higher end) as well as trashing one of my BL-700s. Also I've trashed batteries in it, presumably because the thermistor which is located rather stupidly in my opinion has not picked-up on a very hot battery. My current BL-700 works okay, although sometimes I notice one of the batteries is still charging after 3 days and very hot: not good!
For £30-45 depending on the model it shouldn't be hard to put a mini buck converter in there should it? And upgrade it with a nice little colour oled? And fix the charge detection design flaws?
Ah yes, the old 12 volt in the wrong socket deal! I recently learned that this can happen to computers as well. I was trying to change an old Toughbook over to Linux the other day, the unit came without a CD/DVD drive, so I wanted to use an USB external DVD drive that I have for just such purposes. IT was not being seen by the toughbook, so I thought, I will simply plug it into my new Dell Laptop (well a year old) so I plugged her in, again the led on the DVD drive did light but no recognition. So I looked at the drive, and saw a point where you could plug in a 5 volt power supply, with that in mind, I grabbed a wire with a plug on the end, and shoved her in, while still plugged into my DELL. There was a slight wiff of smoke from my DELL, and the screen went dead, the fan stopped and she died. I quickly unplugged the USB drive, and pressed the power button, I was happy to see the circle containing the DELL logo on the screen as my machine returned to life. It appears all that was damaged was the data pins on that USB circuit. The laptop still has the USB 3 port that works fine, and I can power stuff from the other 2 ports but they are no longer available to transfer data. Guess I can live with that, I am going to get a bottle of red testers pla paint and color all my 12 volt plugs red to keep me aware of this danger
I do have the Technoline BC450 which is a smaller model with less charge current and it runs off 12 Volts! Not sure why they went for the lower voltage on higher charge currents, probably to reduce losses but I'm not sure...
I knew it wasn't just me with OCD when I saw that charger reassembled to put in the bin!
The ' Youshiko YC4000' looks like a good replacement for that one. You'll get slightly higher charge rate options, 12v input and as a bonus a USB 5v output. I recently bought the Opus BC-3100 v2.1 and don't have any issues it so far... other than it has a fan, and makes some noise... but I suppose it does need to cool itself when charging 3xAA at 1A each and discharging a li-ion cell at 1A to check it's capacity :D
Ever fixed it, Julian? I had the same accident.
I feel so sorry for you. Mine did the same thing and they aren't cheap
It looks like one of the traces from the power jack snakes down the left hand side of the charger and goes to one of the blowen 3 pin devices. Hopefully that saved the micro from damage.
Just recieved a Nitecore Digicharger D4, looks really promising so far. It has a really nice display and 12/230V.
Do you think there is notable loss going through the 12 to 3V? Since you are running of solar..
its going to need 3v sooner or later as the rough charging voltage for the batteries, so either lose it externally or internnally to the charger, but dc-dc converters are pretty efficient
I thoroughly enjoy your uploads, I'm waiting with baited breath to see how you're proceeding with your arduino quadcopter.
On a totally different note (hello Julian), are you in a position to advise on the pros and cons of low cost hot air/soldering stations by any chance?
On your earlier video showing this charger, I thought "why not put a cheap 12v->3v switcher inside and wire it in so it's powered off your 12v supply like everything else?" I'm viewing these a year and more after you made them but it might be something to consider in the future.
That's odd, I have the Technoline BC-700 and it has EXACTLY the same specs. Are the ones in the UK BL-700? Who knows...
I will never understand the product naming of some companies...
The MAHA charger has a seperate thermistor for each cell. I have had one fail by a static discharge into a battery terminal, but it only zapped a cmos analog switch chip that was easy to replace. While I was in there, I added a 10uf ceramic cap across the small electrolytic that bypasses the supply bus, where it feeds the four switching charge regulators. It was way too small to handle the ripple current while charging 4 cells at max charge current..
aha heres an idea for a project/video! If most of us looked in our junk boxes we'd find an old charger case of some type or other. These things are sort of generic and there are lots of cheap "building blocks" on ebay, maybe a little recycling too . . What do you reckon Julian, Clive ?? could be fun, maybe some sparkes too ! ! !
there's an extra resistor on the side where there's one missing on the top row (it looks like they're all 5 one Ohm in parallel).
You can set the charge current of the larger charger. I have the same one.
It's probably best that you label your connections to prevent problems like that in the future at least the device didn't fail because of quality issues. I have the MAHA charger that also will not charge certain low batteries and I also believe it has damaged some good batteries. I wouldn't pay another £50.00 to replace it. It has lasted a few years though.
I've had the PowerEx C9000 WizardOne now for a few years. On mine, soon as you put a battery in, press ENTER (to select 'charge' from the menu on the left). The next screen that flashes up on mine is "Charge Rate" that I can select from 100ma to 2000ma (at 100ma intervals) using the up/down arrow keys. Then ENTER again to select.
What he said... I have two of these, and rewinded 3 times to check if I heard it right. You definitely can set charge rate.
Doc Gonzo I meant the default charge rate - the current applied if you put batteries in and don't press any buttons.
Ah, I see. That is true, but, what do you charge in your Powerex mostly? Eneloops, right? And I've been told that a good rule of thumb is charge your cells with half the rate of their capacity. So in that way, the Powerex default is good for Eneloops. Did you know it was/is(?) also sold under the Memorex brand?
I think it might be time to permanently mount one of your many step-down DC-DC converter PCBs onto the back of that Technoline charger, so that particular mistake can never ever happen again. Cheers!!
I think you could easily add a backlight to that display with a couple of LEDs. Depends how opaque the back of the LCD is.
Darren Nash
Germany company maybe, but its obviously product of china
jusb1066 it's also sold under the names Lacrosse and Voltcraft.
Those chargers have absolutely no regulation on the pcb. They are so critical to the power supply voltage, that putting 12v in there will dump way more than the displyed current into the cells, so much it way overheats the switching mosfets. Your Powerex has a regulator near the power jack. It's wastefull, but just keep the input volt as low as the charger will operate when you're on battery/solar power. Ie. if it runs at 9v, as most of those regulators will, then thst's less energy wasted wa
urgh... no over voltage protection with MOVs or diode clamps and no inverse voltage protection with diodes :/
Hey, it's meant to be powered from low voltage DC. MOVs would be completely useless because they can only clamp above a few tens of volts, but by that time everything on the board would already be fried. I agree that a diode to protect from reverse polarity could be good, but at least the plug has the standard configuration.
Has anyone checked out the new Legion 2 battery on the PLX Devices website? Supposed to be the worlds first battery with Artificial Intelligence.
it would be great if you'd increase the bitrate of your video or the encoding scheme... somewhat blurry and blocky at places. Makes it hard to distinguish small detail :)
Doesn't have anything to do with my resolution. I have 100Mb/s internet connection and 27" full HD monitor and I did check my video resolution options when I noticed that. It's about the bitrate of the video combined with some encoding artifacts that make some details mushy. :/Darren Nash
Mtaalas I'm pretty sure julian is recording with a nexus 4, so tbh, I think he's doing a pretty good job with the quality. Also, the magnifying glass can't help the image quality in the closeups.
I have a BL700 but mine is a La Crosse brand. Other than that it looks identical.
just done this with my BC 1000 with 4 cells in grrr proper pissed off but there is a BL700N out now
There are no resistors missing because there are 5 1ohm resistors per battery cell :)
theden.se Quite right - I can see now there's one round the side.
At first I thought the powerex had an E-Ink screen. :)
indask8 The contrast is very good, a bit like e-ink, but the narrow viewing angle spoils the effect.
Voltcraft IPC1 has the same behavior :-)
Fault? You where set up for failure, that plug and 3V is just evil.
I can't understand this - I have multiple items that use the same plug and they are all different voltages. Why would anyone assume anything is just 12v without checking what the device wants? In this case the 3V is stated in large clear white letters - not like it's tiny indentations that you have to hold the light at just the right angle to read or anything. No-one was set up for failure here. I perfectly understand wanting to use alternate plugs or power sources but if you aren't going to use the supplied adaptor it's absolutely the users responsibility to check.
"totally my fault i put 12 volts into it...." now i have a new favourite charger ? WTF ... if you put gasoline in your "favourite diesel car" would you suddenly decide on a new favourite car after it breaks??? LOL just seems odd to me but who cares, it is not important..... by the way, i think i know why the resistors are missing [ i could make up some sarcastic comment right now but i won't LOL] i think it has to do with socket 1and4 being able to be programed differently on the bc-1000
Exactly the same thing happened to me (:
Yeahp, that's the 1st 3V charger of that type that I've seen....and it's proven really annoying...!!!
dont look on ebay now, theres one might bid on !