Battery bms shutoff

[621gears]

Originally Posted by Pat911

30 miles is to be expected from a setup like yours. Let us know how you go recalibrating.

I can probably get 5-10 more if I drive conservatively. Right now the novelty of high acceleration and speed has not worn off yet, lol.

[DaveMJ]

What meter do you have?

Sent from my SM-A526U1 using Tapatalk

[621gears]

Originally Posted by DaveMJ

What meter do you have?

Sent from my SM-A526U1 using Tapatalk

It is an Allied Battery meter.

[DaveMJ]

Originally Posted by 621gears

It is an Allied Battery meter.

Allied have two gauges.

1. Simple Voltmeter - very inaccurate.

Meter 1.jpg

2. Shunt Meter - much more useful.

Meter 2.jpg

If you have option 1 - throw it away. If you have option 2 - check calibration and wiring.

[621gears]

Originally Posted by DaveMJ

Allied have two gauges.

1. Simple Voltmeter - very inaccurate.

Attachment 233387

2. Shunt Meter - much more useful.

Attachment 233388

If you have option 1 - throw it away. If you have option 2 - check calibration and wiring.

I have option 2. I figured it out. The shunt attaches to one battery so you have to calibrate it for one battery, mine is 18ah, once I did that I got the correct reading, Heck yeh!

[Pat911]

The shunt should attach to all batteries, measuring the current in/out of the entire pack.

[621gears]

Originally Posted by Pat911

The shunt should attach to all batteries, measuring the current in/out of the entire pack.

This particular meter from Allied only has one shunt. Their tech told me to change the setting to 18ah instead of 108ah.

[Pat911]

That’s a workaround. To correctly measure SOC of the entire pack all batteries should be connected in parallel then the shunt is connected between the pack negative and the load/charger.

[DaveMJ]

Originally Posted by Pat911

That’s a workaround. To correctly measure SOC of the entire pack all batteries should be connected in parallel then the shunt is connected between the pack negative and the load/charger.

Agreed - connect all battery positives together & connect all battery negatives together. Mount the shunt on one battery negative and connect the load & charger to the other side of the shunt. Set the gauge to total pack capacity.

[621gears]

Originally Posted by Pat911

That’s a workaround. To correctly measure SOC of the entire pack all batteries should be connected in parallel then the shunt is connected between the pack negative and the load/charger.

Which terminal is the pack negative and which terminals should the charger be connected to? Currently, the shunt is connected to the negative terminal at the end of the parallel connections and the charger is connected to the positive and negative terminals at the other end that are connected to the controller.