I've been building up some tppacks boards and ran into various minor issues, which I thought it worth recording to save others some hassle.
I am building up:
* one 16-channel CMS/balancer board (v4.2.6)
* 2 LVC/HVC parallel adaptors (v4.1.2)
* 2 meanwell supply controllers (v4.2.6)
LVC/HVC parallel boards first:
One PCB fault, one duff MTC6, BS107P transistors opposite orientation to instructions.
After fitting all the bits and testing each channel response I found that one board (channels 9-16) was fine but two channels on board 1 didn't work. Channel 4 did not switch on low voltage. Channel 7 had the output permanently on. swaping the MTC6 on channel 4 fixed that problem, but it did not fix channel 7. The voltage divider voltage was not the same as the other channels and the resitors measured differntly (in-circuit - always a bit confusing). Eventually I traced the problem to a PCB fault - R220 was shorted to the TC54 output - the resitor circle is too close to the trace so it was just OK on one board and just not OK on the other. Other boards will have this problem until the traces are modified slightly. I have tried to take a photo of this - will try and upload later.
It now tests fine.
The Meanwell controller board:
BS107P goes in opposite orientation, trim pots physically too big, 1 4k7 resistor missing.
The BS107P transistors supplied go in the opposite way round to the instructions/diagrams. i.e they face towards the tabs, not away. Also the supplied trimmers have the wrong pin spacings. It was just possible to bend them to go it, after enlarging the holes slightly but it was a pain. Getting the right ones would be much better. I just posted the Mouser BOM provided, so I'm not quite sure why that didn't work - presumably part substitution (it's a couple of months ago now, so I'd have to check the details)
A n updated BOM would be a good idea.
This board seemed to work OK once assembled. (I haven't finished testing it yet)
Next the BMS/Balancer board:
BOM is for LiPO variant - change it for LiFePO4 variant.
4k7 resistors missing.
Note that the standard BOM is for the LiPo battery resistor values. You need to change that for the LiFePo4 resistors. I failed to grok this in advance, so had to go shopping again for the right resistors.
When I bought replacement 4k7 resistors I ended getting the 'standard size' ones, not the little tiddly ones used on these designs (which of course don't fit very well). That'll be my fault, but I don;t know what the magic package term for the small ones is (what should one be looking for)?
Mouser sent 7 instead of 8 diodes, which was tiresome, but as these are very average diodes I found a spare in my bits box which I think should be OK.
Note that the BOM includes a male 18-way connector and crimps, but not the corresponding female connector, so you need to go and buy thattoo (and more crimps) before you can actually use it properly (or pick your own connector)
The instructions don't actually say which size/model the hammond box required is. I had to ask Gary for a reminder.
This board seemed to work perfectly once assembled.
I am building up:
* one 16-channel CMS/balancer board (v4.2.6)
* 2 LVC/HVC parallel adaptors (v4.1.2)
* 2 meanwell supply controllers (v4.2.6)
LVC/HVC parallel boards first:
One PCB fault, one duff MTC6, BS107P transistors opposite orientation to instructions.
After fitting all the bits and testing each channel response I found that one board (channels 9-16) was fine but two channels on board 1 didn't work. Channel 4 did not switch on low voltage. Channel 7 had the output permanently on. swaping the MTC6 on channel 4 fixed that problem, but it did not fix channel 7. The voltage divider voltage was not the same as the other channels and the resitors measured differntly (in-circuit - always a bit confusing). Eventually I traced the problem to a PCB fault - R220 was shorted to the TC54 output - the resitor circle is too close to the trace so it was just OK on one board and just not OK on the other. Other boards will have this problem until the traces are modified slightly. I have tried to take a photo of this - will try and upload later.
It now tests fine.
The Meanwell controller board:
BS107P goes in opposite orientation, trim pots physically too big, 1 4k7 resistor missing.
The BS107P transistors supplied go in the opposite way round to the instructions/diagrams. i.e they face towards the tabs, not away. Also the supplied trimmers have the wrong pin spacings. It was just possible to bend them to go it, after enlarging the holes slightly but it was a pain. Getting the right ones would be much better. I just posted the Mouser BOM provided, so I'm not quite sure why that didn't work - presumably part substitution (it's a couple of months ago now, so I'd have to check the details)
A n updated BOM would be a good idea.
This board seemed to work OK once assembled. (I haven't finished testing it yet)
Next the BMS/Balancer board:
BOM is for LiPO variant - change it for LiFePO4 variant.
4k7 resistors missing.
Note that the standard BOM is for the LiPo battery resistor values. You need to change that for the LiFePo4 resistors. I failed to grok this in advance, so had to go shopping again for the right resistors.
When I bought replacement 4k7 resistors I ended getting the 'standard size' ones, not the little tiddly ones used on these designs (which of course don't fit very well). That'll be my fault, but I don;t know what the magic package term for the small ones is (what should one be looking for)?
Mouser sent 7 instead of 8 diodes, which was tiresome, but as these are very average diodes I found a spare in my bits box which I think should be OK.
Note that the BOM includes a male 18-way connector and crimps, but not the corresponding female connector, so you need to go and buy thattoo (and more crimps) before you can actually use it properly (or pick your own connector)
The instructions don't actually say which size/model the hammond box required is. I had to ask Gary for a reminder.
This board seemed to work perfectly once assembled.
