Simplest possible HV wiring schematic

[Scrappyjoe]

Hello there. I have seen many wiring diagrams while researching EV conversions, and am generally able to comprehend about 70% of them. I recently came across one which I 100% understood, and I thought it would be of good benefit to the community to use it as a base for an updated one that I upload to the wiki.

With that in mind - Old Greybeards Of The Forum, can you please take a look and comment on whether this schematic makes sense? In particular,

1. Can we think about our HV circuit as laying out a single HV 'rail' with the battery on one end and the inverter on the other?
2. Is the placement of the negative contactor and precharge circuit correct?
3. Any other components you can think of? A/C compressor, DC charger etc. Where should they go?

In this arrangement, the shunt and charger is 100% on the battery side of the contactors, the DCDC and heater are isolated by the negative contactor but not the precharge circuit, and only the inverter is on the other side of the precharge circuit. This is different from other arrangements I have seen - usually all components except the shunt are on the other side of the precharge circuit from the battery.

It was found at this web page, which is also quite informative http://www.evconvert.com/eve/ev-schematic

113.gif (5.44 KiB) Viewed 2216 times

[janosch]

It's a good question, yes a "DC rail" is a High Voltage bus.

The inverter doesn't have to be "at one end", it is a consumer, like heater or DC-DC, their position in the circuit diagram there are interchangeable. It looks like the inverter was shown on the very right to clear the diagram up.

It appears that in this diagram the pre-charging is done only for the inverter, I would think of it as part of the battery/power source, and would precharge all the loads (the charger will have some capacitors in it as well, but may be able to do its own pre-charge).