DIY Inrush Current Limiter solution needed

Finally got to connecting everything:
Time-delay relay, Tyco Contactor, and a voltage sensing relay for low voltage cutoff.
The low voltage cutoff is not mandatory, but it's a feature I added, because I wasn't happy with the LVD of the inverter (at about 20v, which is pretty low for Lifepo4).

But let's put that aside for this thread.
Basically it all works nicely with the time delay relay. See my previous posts on this thread for connection explanation.

Here are some pictures, I know it looks like a rat's nest, but it's functional.
Inside the little box is the voltage sensing relay, which will "soft" power down the inverter on low voltage (meaning it turns it off via the remote switch). On top is the time-delay relay, and a small busbar for all the negatives.

AntronX said:

Need to add latch circuit to prevent possible contactor chatter or oscillation.

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Yeah, you need a feedback resistor from the output to one of the inputs to add some hysteresis. [My brain is fried right now, not sure what size resistor or to which input, but that's easy to figure out.]

wpns said:

you need a feedback resistor from the output to one of the inputs to add some hysteresis

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Good tip, thanks. Found TI app note about it. I guess I can start with 1:100 feedback ratio or 270k resistor and go lower from there.

kolek said:

@FilterGuy did you ever find a resolution that takes into account this issue?

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No. The best resolution is to make sure the cells are balanced and the BMS never shuts off.