Strange behavior after Alltrax install (jerky throttle and motor cutoff)

[HogKiller]

Called Alltrax to get their thoughts. The tech asked me to disable the “Speed Limit,” which I understand to mean the controller is no longer taking a reading from the speed sensor. This solved Issue #1 immediately. Alltrax says either my speed sensor is bad, or the speed sensor magnet is cracked. I will inspect and report back.

They also solved Issue #2. The tech had me move the Under Voltage slider all the way to the left (16 or 17, can’t remember). The cart climbed right up the curb like a champ. He explained that the load was causing the pack voltage to drop in order to deliver enough amps. At least I think that’s what he said. Anyway, it operates normally now.

[Sergio]

If Your pack is dropping below 38.5v (the setting on your first picture) when you were trying to go up the curb, unfortunately it means you will be shopping for new batteries soon.

[HogKiller]

Originally Posted by Sergio

If Your pack is dropping below 38.5v (the setting on your first picture) when you were trying to go up the curb, unfortunately it means you will be shopping for new batteries soon.

I totally agree. I even asked the tech this question. He then had me log my data to an excel spreadsheet, and it never dropped even remotely close to that low while I climbed the curb. But all I know is that after disabling the Speed Limit and dragging the Under Voltage slider all the way to the left, the cart went right up the curb like I would expect.

He sorta shrugged his shoulders over the phone and inferred “Hey, we fixed it didn’t we?” I couldn’t argue with that.

[Sergio]

He made the symptoms go away, but fixed...

I hope everything works well after you get the speed sensor enabled again.

[HogKiller]

Originally Posted by Sergio

He made the symptoms go away, but fixed...

I hope everything works well after you get the speed sensor enabled again.

Sergio, what did you think was causing Issue #2?

[Sergio]

There are some questionable cause/effects based on the symptoms that were described in the thread.

Speed sensors don't know which way the motor is turning so it should have caused issues in both directions.

The Controller does not cut off at the low voltage setting, it only reduces the battery current usage to prevent the pack from dropping below the set value.

Hard to imagine your pack could not deliver the current needed for the motor to climb a small curb without dropping more than 10v.

You guys also verified by logging the battery was not dropping under load.

You have lost a lot of performance by not having the speed sensor enabled so that needs to be resolved.

At this point it would be best to follow the Alltrax suggestions and please let us know how it turns out.

[HogKiller]

Originally Posted by Sergio

Speed sensors don't know which way the motor is turning so it should have caused issues in both directions.

I asked the tech this question as well. He essentially said that I was applying the throttle differently in reverse than in forward. I don't know enough about these things to argue the point, so I left it alone.

[Sergio]

While You are waiting on the new speed sensor, make sure the cables on the motor connections are tight and that the Solenoid does not have any extra wires on the big stud that goes to the controller.

Make sure the Controller B- cable lug is first and the other negative wires go on top.

The best stacking connection on Controller B+ would be Motor Cable first then cable from Solenoid on top.

You should also remove the speed sensor and make sure the magnet is secure and intact on the motor shaft.

[HogKiller]

UPDATE: speed sensor magnet was GTG. Swapped a new speed sensor in and that appears to have completely solved Issue #1.

Issue #2 continues to be completely resolved by simply moving the Under Voltage slider all the way to the left using Toolkit (17v is as far as they'll go). I even tested it today, by climbing the curb successfully, then setting UV back to 38.5, and the cart would not climb the curb. And to reiterate what I said previously, the Excel spreadsheet generated by the monitor log shows the battery voltage never drops below 44.7 on the climb (Motor Current was 341.8 at that moment, for those keeping score). Unless someone advises otherwise, I will consider Issue #2 resolved by moving the UV sliders all the way to the left.

[Sergio]

I am glad it is working but there must have been other factors in your setup that affect how those settings interreact with each other.

I always used 38.5v for Under Voltage on my FLA batteries and now use 45v with my lithium, as You said even your logs showed the lowest voltage at 44.7v.

Those FSIP torque motors seem to place a large current demand on the batteries.