Battery pack charging problems please help

Hi i have made my battery pack of 50 LG HE4 batteries. I have them in a 10S 5P configuration ending up with max 42V and 12.5Ah.

I have a 10S 60A Suunpower BMS, which i have connected the right way to the pack. The battery leads reads the right values from 3.6V up to 36V

I have also bought a 42V 4A power supply, With a fuse.

I have the two connected via a XT-90 Anti Spark plugs.

My problem is that the pack wont charge.

The powersupply blinks when red to green indicating that the power is cut. I can measure it goes from around 4A to 0 and over and over again. So something is wrong.

I can press the XT90 connector half in and the power will flow constant with 1A. But then the XT90 will get hot, so i pulled it fast.

I can not seem to figure out what is wrong. I have bought and changed the BMS, no smoke or nothing comes from it. So i think it works.

Can it be the resistor in the XT 90 that makes it work weird or what can i do?

I never heard of using an anti-spark connector to connect your charger to the battery. It may be messing with the charger’s sensing circuit. The charger negative to the bms P- pad The charger positive straight to the battery positive Usually, people wire a DC connector that matches the plug on the charger

Its because the BMS uses same port for discharging and charging. Can it be why it got hot?

oh man my charger has some wierd port like an xlr but a lot smaller, would it work normally if i put an xt90 on there

where can i buy one of these ports

I just removed the plug and soldered a XT90

Nope it was not that. What the hell can it be. I have changed the connector to XT60 to test.nothing changed.

Maybe the resistor is messing with your charger

I use the same 3 pin connector. It’s the size of a CB mic plug.

I changed the connector to a standard XT60 but the same problem persisted. What do i do wrong?

Your XT90S is probably bad. Did you replace it with an XT60 loop key?

Here is how I would troubleshoot it:

Bad XT90S Loop key: Replace both connectors with new ones.

If problem persists then it’s either, BMS or charger.

Bad BMS: Remove the BMS from in line, if the board charges fine then the BMS is the problem.

If problem persists, then it’s the charger.

Bad charger: Replace charger.

If problem persists, then there is something wrong with the battery.

Bad Battery: Check all voltages followed by welds and solder joints if it was DIY.

Hi everyone, after months of waiting for new bms, then seeing that it was not a problem with the BMS. i bought a new charger and now it charges flawlessly. But weirdly enough with only 1 Amp but the charger is 2A