I got mail: 2 new panel meters, one double switch relay, two tiny relays for switching purposes and some 20 amp diodes.
I'll use the diodes to prevent back current, which I think limits net flow now.
The panel meters are to measure voltage and current flow.
The small relays for a push-and-hold style control which will drop off after key off, rather than the switch I keep forgetting now, which causes IMA errors.
The double switch relay will be the first to get used though.
My lamp shunt has a 2S3P setup so it can handle up to 24 Volt, but usually the voltage differential is below 12 Volt.
The current flowing to the IMA pack drops under 3 Ampere then.
I will power the coil in parallel with one 3P group of lamps, switching the other group in series when it is engaged, and parallel when not so it will be either 12V high current or 24 Volt low current.
That should allow for a lot more influx under normal conditions while protecting the system under high use.
It is still waiting because when the mailman left this happened:
on top of other issues and woes that kept us on our toes these last weeks.
Meanwhile, using the 2S3P lamp shunt I use about 1.2 kWh a week, for about 300 miles of driving. The effect of that cannot be more than a few %, and it completely drowns in disturbances like the storm I had to drive through - the same that killed our tree.
On a positive side, the imbalance occuring at the first charge is gone.
On the second charge one pack ended up fully balanced, taking the max 43.8 Volt from the charger without the BMS tripping; all cells below 3.8 Volt.
The other two had the BMS tripping, but were very nearly there. Just a few minutes of gentle balancing by the BMS got them in line.
On the third charge only one pack triggered the BMS.
Since then all packs end up balanced right after the charge.
Moreover, they do so in perfect harmony; all 3 chargers stop just a few tens of seconds apart after over 3 hours of charging!
Resting voltage after being detached for a night is 42.2 or thereabouts; all 3 within a tenth.
Last time I did not even bother to check the voltage. It just works fine.
About the post title:
All this tinkering with batteries and lamps and causing system errors gets on my nerve a bit.
Every strange sound, relay click or whatever sends an alarm signal up my spine. I keep telling myself that it is all normal, or the car behind is making that sound etc. to reassure myself.
When I smelled a burn yesterday right after using EV mode for a while I thought someone must be burning leaves somewhere, but just to be sure I switched off the lamps.
At work I got to the boot and found that a tiny leaf had landed in the boot, right on top of the glass of one of the lamps in my shunt.
It had a burn hole the size of a nail head...
I'll add some wire mesh to shield off the lamps
