Battery Vehicle Society

Programming the pics is the easy part, you will need to do some googling to find the solution/ideas for that.

Yes you could use breadboard, but best bet is make an adapter from pickit 2 to the zif socket gizmo.

Check the asian programmer for breaks in the grey ribbon cable that's a common issue.
I've repaired a couple of mine with that issue.

Dorian/Chris/et al

Q. Are Smiths happy for me to attend there and tinker about with this project in there workshops on the date mentioned Wed 17/10?

Q What is the RV point and who is the contact there at Smiths?

Q Shall we say 11:00AM?

Peter,

Smiths will be happy to have you there. I will confirm with them tomorrow but I propose If you pull up outside reception sign in and then drive round the back to their charger bay so you can plug your car.

11 am is good.

The main contact for us there is Steve Turner. steven.turner@smithelectric.com

Thanks
Chris

Peter,

17th is fine, they say there could be a site access problem whatever that means. they have 3 phase chargers for their vans. what plug do you require to charge your car?

I just need a 13amp socket.

Site access problems does not sound hopeful. Find out what that means please.

Hi,

Basically I think they are going to run an extension lead out of the office window for you.

We seem to have a serious problem, there are more melted chips/chip holders on the slave boards and another fried load resistor. Surely this can't be from heat alone?

The whole system seems to be wired up fundamentally wrongly somehow to me.

Are the slave cell connections fused as they should be with a 1A fast blow fuse in each lead?
If they are you should not have melted tracks or blown boards even if something is wrong.

If the connections from the cells to the slaves are off by even one cell then the whole thing will die.
Check again the connections from the cells to the slave boards.
Remind me again how many cells/slave boards you have?

The Master and Slave boards must not share the same ground.
The Master and lcd screen are best powered by an isolated 12v dc-dc converter.

I have never had melted chips or blown boards.

I don't have any spare master/slave boards so do not wire that up until I get there.

Still waiting for the pics of the boards in situ with connections to the pack.
I need a series of detailed pics to have any hope of fxing it next week.

We are almost certain to need something from my workshop.
If I haven't got it with me then you are buggered as I am away on holiday for the following two weeks.
I'm rapidly comming round to the idea that you should bring the batteries and BMS here to me.
Please discuss this with them and bring the batteries and bms/master etc down to me if at all possible.

Peter

The nicely melted chips.

Will send pictures tomorrow of the car setup but it is very confusing. In fact that's an understatement its a nightmare to see what wires go where. Its probably not going to help you much.

if you can get some tape (we call it masking tape here but any label tape would work) and write what the other end of the wire is connected to, so you can see where it connects on the board and also the label that says where the other end of the wire goes, i think it would help a lot

Looking at the picture of your burned board you can see that the 12 ohm load resistor for cell 16 (R2P) is charred. The only way this can happen is if the voltage across that resistor is too high, it will never char like that connected across only one cell. Probably the pack to slave wiring is incorrect, somehow you have got more than 1 cell connected across that slave circuit.

In addition to having a fuse at each cell connection (you need to use fuses rated for full pack voltage) you should have some sort of multi-pole connector at each slave. This will allow you to confirm correct voltages at the connector pins before plugging it into the slave and also allow you to easily swap slave boards if required.

If the wiring is a rats nest you should probably carefully pull it out and redo it. Use lots of cable ties to keep it tidy, but most importantly you need a schematic to work to. Even if it's drawn on the back of a napkin in crayon you must have a schematic! Post a copy here of your schematic so we can check it for errors and then work to it.

Make sure anyone working on the pack/bms has the skills to work with high voltage DC circuits which can be lethal!