Old BMS General Thread

[GregsGarage]

Slaves without a Master, very cool. But are they still slaves then?

I like that idea. Will soon post what I have been working on regarding a BMS, I know I said last week, but hopefully this week. Still working on a few bugs.

Greg

[retepsnikrep]

Bit of a glitch with cell delivery I now expect them next Monday.

Master V1.00 and Slave PCB V2.00 just about done.

I'm already working on Master V2.00

V2.00 will include ps2 keyboard support and enhanced button/menu control. Don't hold your breath though it will be a few months away.

Anyway, I've adapted the Slave boards to be dual purpose.

Depending on how you assemble the Slaves (using the same components ) you can have the Analogue style solution with an opto for over and under V and on board balancing load, or they can be configured for use with the Master Board, with Master Data Bus, Slave Command Bus and on board balancing/bypass load.

My design borrows ideas heavily from a number of BMS systems inc, analogue clampers and more sophisticated pic based systems. There is lot's of info out there in the public domain.

Latest updates here.

http://www.solarvan.co.uk/bms/SlaveAnal ... 8_v200.txt

http://www.solarvan.co.uk/bms/SlaveDigi ... 8_v200.txt

http://www.solarvan.co.uk/bms/Slave120808.jpg

Note on the Slave board V2.00 components J2,R1,U3 are used in the Digital configuration, but they are moved to J5,R11,U4 in the Analogue version. J5,R11,U4 are ommited in the Digital version. The same three components do both jobs and the board accomodates either

http://www.solarvan.co.uk/bms/Master120808.jpg

The Master reset switch is now moved off the pcb in this final version for the Master V1.00. The Master pcb uses 0.1" pitch screw terminals for all the connections except the programming inputs, which are 3 simple Sil 0.1" pins as for the Slave.

[retepsnikrep]

Master Pcb

http://www.solarvan.co.uk/bms/MasterPcb.jpg

http://www.solarvan.co.uk/bms/MasterPcbIdent.jpg

Basically Inputs on the left, outputs on the right.

Master Board is 105mm x 100mm square with 3mm mounting holes in each corner. Standard format, thickness etc.

Got to check it now

[ChrisB]

Thats looking all very nice now Peter, loving the display unit that will show all the data

May I ask what software your using for all the design work ?

ChrisB

[retepsnikrep]

The pcb man is using Protel or Orcad, Nice bloke, if he is happy I'll pass on his details once he's finished this project 40 years experience in pcb design I believe.

I'm using Proteus Isis for the Schematics and exporting Netlists for the pcb chapie in Racal format, all Greek to me though Proteus VSM can also simulate your schematics with the Picaxe chips, I did'nt use this feature much though.

I am using the free Picaxe 'Basic' software editor to write the programs. It's very good, with useful simulation functions, and downloads the finished software straight to the pics using a simple serial or usb cable.

Nice and easy for punters to upgrade the software. The Picaxe forum is very friendly and incredibly knowledgable, I've posed a few questions during development and they have come up with an answer.

http://www.picaxeforum.co.uk/

It's nice it's finally comming together.

[qdos]

Excellent ! I had someone asking me the otherday for information on who could do PCB drawings. Hopefully they are reading this thread This is superb stuff Peter!

[GregsGarage]

Bit of a glitch with cell delivery I now expect them next Monday.

My cells took just over a week after clearing customs before I got my hands on them, I think it has to do with finding the correct container on the ship and then sorting through it to find your shipment.

Anyway, I've adapted the Slave boards to be dual purpose.

Depending on how you assemble the Slaves (using the same components ) you can have the Analogue style solution with an opto for over and under V and on board balancing load, or they can be configured for use with the Master Board, with Master Data Bus, Slave Command Bus and on board balancing/bypass load.

Would it be possible to build the slaves with both options (ie, J2, R1, U3 and J5, U4, R11) and then load the correct program (and maybe set a jumper)? I am thinking that the analogue version would work with what I am trying to do and since I just "let the smoke out" of one of my boards, I might explore that option.

Greg

[retepsnikrep]

Anyway, I've adapted the Slave boards to be dual purpose.

Depending on how you assemble the Slaves (using the same components ) you can have the Analogue style solution with an opto for over and under V and on board balancing load, or they can be configured for use with the Master Board, with Master Data Bus, Slave Command Bus and on board balancing/bypass load.

Would it be possible to build the slaves with both options (ie, J2, R1, U3 and J5, U4, R11) and then load the correct program (and maybe set a jumper)? I am thinking that the analogue version would work with what I am trying to do and since I just "let the smoke out" of one of my boards, I might explore that option.

Greg

Sad you had a smoke issue Please let us know what you were doing, trying to do, what went wrong and why? I/we need to learn from your experience as well. I am keen to see you efforts.

Anyway the software is not affected if you decide to include both sets of components, (It may make the data output to the next slave slightly less effcient at low voltages however) but what you could do is put a socket on the board for U4 & U3 and then just move the optocoupler from one socket to the other to suit your setup.

Opto in U3 is the digital option.

Opto in U4 is the analogue option.

I did try to make it flexible, just hope it works!!!

If you had both sets installed and used the Slave in the digital configuration the Sink Input on P4 (pin3) would be trying to sink the power for 3 leds U4, D2 and the led opto on the next slave in the chain. The PIC current limit is 20ma but the lower the voltage the less drive current available, so fewer led's to drive is better.

The eagle eyed amongst you will have noted that the Master Bus Output is now on Pic P2 (pin5) on the latest Slave Schematic. This is because the Pic has a pwm out function available on that pin, and I may want to use that for variable charger control in Analogue mode At the moment in Analogue mode the the pic simply turns the opto full on when Cell V > Abs Max Cell V, however some sort of gradual change is probably better, but I haven't included that in the Analogue software yet

[retepsnikrep]

Now I know a lot of people have looked at this thread, and I shall shortly be sending off my first order to China for the Slave & Master Boards. It's a 15 day lead time.

Cost's will be about £1.50 per bare Slave pcb and £15.00 per bare Master pcb. If I can get a few more orders for the Master, say 50 then price comes down a lot to about £5.00 each.

Apart from Greg does anyone want any?

If so e-mail me at peterATsolarvan.gotadsl.co.uk to be included.

Replace AT in above to do the e-mail thing.

Last date for orders Monday 18th Aug. I shall send it off then.

[retepsnikrep]

Slave Pcb

http://www.solarvan.co.uk/bms/SlavePcb.jpg

http://www.solarvan.co.uk/bms/SlavePcbIdent.jpg

Slave Board is W 40mm x L 130mm with 3 pairs of mounting holes spaced at 65mm (6.5mm hole) , 83mm and 106mm (8.5mm holes)

Users can select the analogue or digital option by installing the opto in either U3 or U4 position and load the appropriate software.

They can also cut the board down to suit (cut the ends off if they are using smaller cells) I'll be using the 65mm holes for my 40ah cells.

Standard double sided Pcb format, thickness etc.