It's very likely you can find a substitue part for the resistor that is in stock.
You can also try Digikey.
Which ones are out of stock?
You can also try Digikey.
Which ones are out of stock?
Building my new BMS.
- Thread starter Patriot
- Start date
Patriot
10 kW
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- Aug 7, 2008
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Waiting for shipment of following items....
- 299-4.7K-RC 4.7Kohms 1
Xicon 1/8W 5% Carbon Film Resistors
This product is expected to be in stock by 03-02-09.
- 270-180K-RC 180Kohms 1% 16
Xicon 1/8W 1% Metal Film Resistors
This product is expected to be in stock by 01-20-09.
- 286-6.8-RC 6.8ohms 16
Xicon 5W Small Metal Oxide Resistors
This product is expected to be in stock by 01-20-09.
- 299-4.7K-RC 4.7Kohms 1
Xicon 1/8W 5% Carbon Film Resistors
This product is expected to be in stock by 03-02-09.
- 270-180K-RC 180Kohms 1% 16
Xicon 1/8W 1% Metal Film Resistors
This product is expected to be in stock by 01-20-09.
- 286-6.8-RC 6.8ohms 16
Xicon 5W Small Metal Oxide Resistors
This product is expected to be in stock by 01-20-09.
You could use the 15 ohm 2 watt shunt resistors instead if they in stock.
I started with the 6.8 5 watts, but they got so hot that the hot melt glue that I had used to tack some wires down on the bottom of the board melts. I switched over to the 15 ohms and it worked just the same.
I've found that with my 16 cell PSI pack all shunts go on within 15 seconds of each other. It doesn't seem like it needs much balancing, but then again I have new cells, maybe things will change after a lot of use.
I'm not sure how much balancing really needs to be done with these PSI cells.
it seems that the cells go up to 3.7 volts and then when you unplug everything each cell settles down to about 3.35 volts after a minute or two.
I started with the 6.8 5 watts, but they got so hot that the hot melt glue that I had used to tack some wires down on the bottom of the board melts. I switched over to the 15 ohms and it worked just the same.
I've found that with my 16 cell PSI pack all shunts go on within 15 seconds of each other. It doesn't seem like it needs much balancing, but then again I have new cells, maybe things will change after a lot of use.
I'm not sure how much balancing really needs to be done with these PSI cells.
it seems that the cells go up to 3.7 volts and then when you unplug everything each cell settles down to about 3.35 volts after a minute or two.
Patriot said:
Icewrench
10 kW
So the parts that I found to be most likely to fail when pack lead are criss crossed or other bad shorting stuff happens are ksa 931 { q 101 } , tc54 { u 101 } lm 431 { u 102 } and for good measure I also wiped out 1 2n3906 transistor. Now it is working and balancing 1 12 cell pack very nicely. Very impressive. Now it`s on to pack building 101. 
8)
8)
fechter said:
It appears that we goofed when we specified the TC54 parts and many of you may be using the complementary output (VC) version because the open drain (VN) version was not available in the right voltage.
What this means is you should not use the LVC test function as it will be shorting the output of one TC54, which could possibly cause it to fail. Otherwise the LVC will work fine, but I'll have to think of a better way to test it.
steveo
100 kW
fechter said:
What gauge wires did you use there fechter? If i need to make mega long balance lead like 4-5 feet what wire would you recommend.
thanks
-steveo
Patriot
10 kW
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^^^ I would think something like 20-22awg should still work fine. I say this because if it's copper wire, and only a few feet, then the losses will be minimal. Also, the amperage going to charge each individual cell is very low, so I think you're talking about losses in voltage of something in the realm of hundreth's, or even thousandth's of one volt. I think mine are 22awg.
If you want to be on the safe side, go with 20awg.
If you want to be on the safe side, go with 20awg.
steveo said:
I'm using 18ga. there. 5 feet is pretty long, but I think 20ga. will still be OK.
If the cells are perfectly matched, there is no current in the wires. In real life, when balancing, the voltage drop in the wire will make the cell voltages off a few millivolts until the balancing current drops. It won't hurt anything. It will make no difference during discharge (the TC54's only draw about 1uA on standby).
The two end wires (pack + and - connections) need to be heavier to take the full charging current.
Here is an online wire resistance calculator.
http://www.stealth316.com/2-wire-resistance.htm
If using 10 feet (back and fourth) 20 AWG wire the voltage drop is 0.1 volts per ampere, that is, the resistance is 0.1 ohm. Thats seems high to me. Try shorten the wire.
http://www.stealth316.com/2-wire-resistance.htm
If using 10 feet (back and fourth) 20 AWG wire the voltage drop is 0.1 volts per ampere, that is, the resistance is 0.1 ohm. Thats seems high to me. Try shorten the wire.
Hi,
I'm building my v.2.2 board and run into weird problem that I couldn't find from the original long-long thread.
My problem is that I haven't seen main LED to be red.
I have assembled first 4 channels.
Then I made the test described in the manual and I got all the LED-s (main LED green + 4 orange channels) lit when I connected BMS to the power supply (~15V) without cells.
When I connected also batteries and then plugged everything to charger then also main LED was immediately green. I kept it on for a while and when one cell hit 3.70V, the orange LED came on and the channel started throttling (resistor went hot and cell voltage was kept on 3.7).
I also performed this test on that page http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=5416&st=0&sk=t&sd=a&start=795 and it was kind of successful (all LED's went out, including the main one).
What you think could be wrong or from where to start searching?
I'm building my v.2.2 board and run into weird problem that I couldn't find from the original long-long thread.
My problem is that I haven't seen main LED to be red.
I have assembled first 4 channels.
Then I made the test described in the manual and I got all the LED-s (main LED green + 4 orange channels) lit when I connected BMS to the power supply (~15V) without cells.
When I connected also batteries and then plugged everything to charger then also main LED was immediately green. I kept it on for a while and when one cell hit 3.70V, the orange LED came on and the channel started throttling (resistor went hot and cell voltage was kept on 3.7).
I also performed this test on that page http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=5416&st=0&sk=t&sd=a&start=795 and it was kind of successful (all LED's went out, including the main one).
What you think could be wrong or from where to start searching?
Icewrench
10 kW
Never mind. 
Sounds like the red/green LED might be backwards. When it is green (normally) the charge current should stop. The fact that it lights up green indicates the 12v supply is working.
Try jumpering the all shunts line to ground for a moment and see if it triggers the latch and you get red.
Try jumpering the all shunts line to ground for a moment and see if it triggers the latch and you get red.
fechter said:
OK, now I got it red also. LED was rotated 120 degrees, so that the middle leg was in the hole for G and the shortest leg was in the GND hole. Somehow it worked, but only green.
Now when I apply 15V to empty board, main LED will lit as red and all assembled shunts lit also. After shorting all shunts line to GND, shunt leds go down and main LED turns to green.
Patriot
10 kW
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I have a question about the diodes.
On the board, some are labelled D1, D2, D-101, and D-102. I assume they are the all the same diodes that came with my parts order, since I have like 34 of them, and that the diagram shows them installed opposite each other with the stripes/stops opposing each other.
I was just wondering why they had the differant labelling if they are the same type of diode? Is that schematic specific?
On the board, some are labelled D1, D2, D-101, and D-102. I assume they are the all the same diodes that came with my parts order, since I have like 34 of them, and that the diagram shows them installed opposite each other with the stripes/stops opposing each other.
I was just wondering why they had the differant labelling if they are the same type of diode? Is that schematic specific?
Patriot said:
That's just the standard way of designating parts in a circuit. Even if you have 34 of the same part, you need to label them individually so you can refer to them specifically for troubleshooting, whatever. All the diodes are the same except for the zener.
Patriot
10 kW
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^^ That's what I thought.
Anyway, I just got email, and UPS is out for delivery today for the remainder of my parts. Specifically, the 180k resistors.
I've been holding off installing any other parts until I get all resistors and diodes installed. Then, I'll do the opti-couplers and capacitors, etc.
In the meantime, I decided to build a box for my BMS. The problem I'm having, is that I wanted to install the BMS above the controller in my box. That way I can easily see the LED's when charging. However, the BMS board is too big to fit in my box. The 16-channel setup is much longer than I thought.
What I have to do now, is try and mount it on its side, and attach it to the front of my battery. Unfortunately, doing this will put it in the front of my box, and I won't be able to easily see the LED's. I may have to use a small mirror to look around the front side of it, to see the LED's. This should work, but is a bit of a hassle.
As you can see, my box has holes on one side for air to come in, and a long slot on the other side where the leads come out, to allow heat to escape. The box will be mounted sideways on the front of the battery with the holes down, and leads coming out the top.
Anyway, I just got email, and UPS is out for delivery today for the remainder of my parts. Specifically, the 180k resistors.
I've been holding off installing any other parts until I get all resistors and diodes installed. Then, I'll do the opti-couplers and capacitors, etc.
In the meantime, I decided to build a box for my BMS. The problem I'm having, is that I wanted to install the BMS above the controller in my box. That way I can easily see the LED's when charging. However, the BMS board is too big to fit in my box. The 16-channel setup is much longer than I thought.
What I have to do now, is try and mount it on its side, and attach it to the front of my battery. Unfortunately, doing this will put it in the front of my box, and I won't be able to easily see the LED's. I may have to use a small mirror to look around the front side of it, to see the LED's. This should work, but is a bit of a hassle.
As you can see, my box has holes on one side for air to come in, and a long slot on the other side where the leads come out, to allow heat to escape. The box will be mounted sideways on the front of the battery with the holes down, and leads coming out the top.
I thought about using some cheap plastic optical fibers glued to the LEDs to view them remotely. It would be possible to either glue the fibers directly to the end of the LED (hot melt?) or drill a shallow hole in the end of the LED to make the fiber attachment more secure.
Using fibers, you could remotely view the LEDs and you could make a cool display panel for the remote end of the fibers.
Using fibers, you could remotely view the LEDs and you could make a cool display panel for the remote end of the fibers.
Doctorbass
100 GW
Hot glue is a nice solution but the best would be the little hole in the led like Ftchter suggested but to add some transparent epoxy inside that hole to adapt the refraction index of the led case to the fibre.. by that way the maximum light transmision would be acheived.
also for finding cheap fiber, just look for 1$ stores stuff.. they often keep some decorative stuff with led and fiber..
doc, your optical technician!
also for finding cheap fiber, just look for 1$ stores stuff.. they often keep some decorative stuff with led and fiber..
doc, your optical technician!
Patriot
10 kW
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Another question.
I noticed my 48v charger has a three pronged XLR connector, but only uses two leads. The third is a spare, I guess.
Instead of adding a second GND lead from the BMS board all the way to the connector, can I just add a small jumper to connect the two "Charger GND" holes on the BMS board itself?
That would be the easiest way, considering they are right next to each other.
The UPS guy is here. The rest of my BMS parts are in my hand. WOOHOOOOO!!!!!!!!!
I noticed my 48v charger has a three pronged XLR connector, but only uses two leads. The third is a spare, I guess.
Instead of adding a second GND lead from the BMS board all the way to the connector, can I just add a small jumper to connect the two "Charger GND" holes on the BMS board itself?
That would be the easiest way, considering they are right next to each other.
The UPS guy is here. The rest of my BMS parts are in my hand. WOOHOOOOO!!!!!!!!!
Doctorbass
100 GW
Patriot said:The UPS guy is here. The rest of my BMS parts are in my hand. WOOHOOOOO!!!!!!!!!
This is like christmas every time that happen to me
whatever UPS, Canadapost, Purolator.. etc<
Doc
Patriot said:Instead of adding a second GND lead from the BMS board all the way to the connector, can I just add a small jumper to connect the two "Charger GND" holes on the BMS board itself?
That would be the easiest way, considering they are right next to each other.
If you did that, then the control circuit would be always on and drain the batteries. You want the control circuit to be off when you aren't charging. You can certainly use the 3rd pin for the jumper in the XLR. That's how I do it. It's easy to find 3 conductor cable. Use an old piece of power cord.
The drawing above looks good.
rossasaurus
1 mW
Hi Patriot,
Since you asked about Isopropyl Alcohol way-back, I thought I'd mention a couple things for the collective knowledge-base; Rubbing Alcohol usually has lanolin in it, I'm assuming to make it less harsh on skin(?), which is not great to have on PCB's. No, it's never listed on the label either.
It's hard to get small quantities of the industrial grade Isopropyl, so there is a way to get more concentrated Isopropyl.
Many pharmacies sell two grades; one, the standard, is I believe 72%, and the other grade is 98% or 99%. Sometimes you'll have to ask for the 99% as some pharmacies keep it behind the counter. My local Safeway has the two together out in the open. This will give a little stronger alcohol with a lesser amount of lanolin.
So, if you can get the pure stuff, do so, followed by the 99%, and if you can't find that, use the standard household stuff.
Since you asked about Isopropyl Alcohol way-back, I thought I'd mention a couple things for the collective knowledge-base; Rubbing Alcohol usually has lanolin in it, I'm assuming to make it less harsh on skin(?), which is not great to have on PCB's. No, it's never listed on the label either.
It's hard to get small quantities of the industrial grade Isopropyl, so there is a way to get more concentrated Isopropyl.
Many pharmacies sell two grades; one, the standard, is I believe 72%, and the other grade is 98% or 99%. Sometimes you'll have to ask for the 99% as some pharmacies keep it behind the counter. My local Safeway has the two together out in the open. This will give a little stronger alcohol with a lesser amount of lanolin.
So, if you can get the pure stuff, do so, followed by the 99%, and if you can't find that, use the standard household stuff.
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