So you turned on the BMS and when you switched on the unity it failed to stay on?
When I turned on the BMS without switching on the Unity, power stayed on for ~2 sec then shut off.
Do you think is a BMS issue, shortly somewhere?
When you do it like I mentioned (BMS first, Unity second) does it stay on?
I did try BMS first then Unity second, did not stay on. Other time BMS on, did not stay on.
Let me go try shorting BMS switch…
Before you go shorting switches, measure the output voltage.
With the BMS you have it should output 1-2V less than the battery voltage in the off position. When turned on it should be the same.
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Measured output voltage across the BMS eSwitch is ~12V in the off position.
Also, tried shorting BMS switch, turning on Unity switch did not power up the system.
Don’t measure on the eswitch, unplug the Unity and measure on the xt connector of the BMS
What voltage are you getting with the BMS switch in the on and off position?
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Measured on the xt connector of BMS, off voltage is ~3.4v. On voltage is ~41.5V, it only stayed on momentarily, then back down to 3.4V.
Ok, then you have some problem there.
Is the latching switch wired correctly?
Can you check if it is working properly with a multimeter?
I shorted the BMS switch, Unity switch on did not power up the system.
Have not check the actual latching switch yet.
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Leave the unity alone for a while. Focus on getting an output from the BMS.
If you short the BMS switch, do you get the same voltage as the battery on the xt connector?
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Shorting BMS switch, xt connector read 3.4V
Then you either have a faulty BMS or have somehow wired it wrong.
Everything was working fine until I bolted down the enclosure.
Your wiring seems correct.
If you measure B- on the BMS and + on the XT connector what do you get?
Across B- and +XT connector, voltage is 41.3V
Sounds like a BMS problem then.