Motor jerks when throttling

I'm just about done converting ebike to new frame and I was test riding and the controller shut off I was at a lowish speed and went full throttle and it turned off, I lost all power and the cycle analyst dropped in voltage and shut off, I was just outside my house so I wheeled it in and tested my battery it shows 52.2v what it was before it turned off, and plugged it back in and it turned on, I jumped back on and noticed it seemed to sag in power, like 50% or more, I then wheeled it back in and sat the rear wheel up and tried to throttle, nothing, I span the wheel and the cycle analyst read the speed out and when I try spin and throttle it jerks

Rear mxus 3k hub motor

Em3ev 18fet controller

48v 59amp continuous battery

Let me know if you need more info

I've tested all the hall sensor leads, they all seem to jump between 0.03v and 5 and I did a test with the phase wires where I free spun the wheel and connected the phase wires to each other in pairs to check for faulty wires and they all creat resistance in the motor

Mitsoevo said:

I lost all power and the cycle analyst dropped in voltage and shut off,

Click to expand...

that means the bms shut off to protect the battery from damage.

either

you're pulling more power than the battery can handle,

or

there's a cell or cells taht are too low, or damaged, or defective, or old, and are sagging below lvc

or

there's a wiring problem cuasing the bms to "think" one of those things is happening

amberwolf said:

Mitsoevo said:

I lost all power and the cycle analyst dropped in voltage and shut off,

Click to expand...

that means the bms shut off to protect the battery from damage.

either

you're pulling more power than the battery can handle,

or

there's a cell or cells taht are too low, or damaged, or defective, or old, and are sagging below lvc

or

there's a wiring problem cuasing the bms to "think" one of those things is happening

Click to expand...

sorry for late reply thank you for the info, it may be too much to ask but this is the controller i have, my battery is 59a and the controller says "60a rated" but doesnt state how many phase amps what would you recommend?

https://em3ev.com/shop/18-fet-irfb4110-infineon-controller/

Mitsoevo said:

sorry for late reply thank you for the info, it may be too much to ask but this is the controller i have, my battery is 59a

Click to expand...

Is your battery 59A, or 59Ah?

They are completely different things, even though they look similar.

Post the complete information about your battery, everything you know about it, and we can try to sort out what it actually is.

FWIW, if the battery is actually 59A capable, and the controller is 60A capable, then the controller *could* be pulling more power than the battery can handle.

But any of the things I listed before could be it, and you'd have to test for each one to eliminate it.

and the controller says "60a rated" but doesnt state how many phase amps what would you recommend?

Click to expand...

You'd have to check your motor's ratings to know what Phase amps to use--it has nothing to do with the battery.

You need to go by the battery amps the controller draws to figure out the load the battery sees. You'd need to check what teh cycle analyst shows for peak battery current, as well as what it shows while you're riding and the voltage sags.

Sometimes a big motor simply kills its controller.

A motor, controller, throttle tester is a good thing to have, when confused what is going on. Once you confirm that the controller and the motor are good, then its time to start looking harder at the last thing it could be, the wires.

It may be a bms sense wire come loose.? If 48v 13s the charge voltage should be 54.6v or very close. See if it takes a full charge.