Adjusting Amature voltage

Hey I have a car that is giving me a code 41 (which is controller overheat) I am going to add a van to help then the controller I don’t have room to add a heat sink and I wanted to use my handheld controller to turn down the Armature voltage or current I was wondering if anyone here near the steps to do this I have a handheld programmer I just forgot the correct way to Enter the programming process and what function #Armature current is

Function 4 is Max Armature Current on the T1. Not sure if its the same on all controllers. I know you have a newer one, I might have a T4 manual in my collection if that’s what you have. I use the PC software so I don’t know the sequence for the handheld sorry.

Thanks for the reply Sorry I should have stated I have a T-2 controller.
I’m pretty sure T-1 and T-2 have the same Control Functions.

Do you know the steps that get you into that setting adjustment?

I have the software so I don’t know how to use the handset. I did find this link which might help:

Ok that looks like it helps.

Function #4 Range 0 to 255

So I’m guessing 255 is the setting for Max current and 0 is for the least amount of current.

(Push 4)
This function allows for the adjustment of the armature
current limit of the control during motoring.Range 150 to 357 amps
Set 0 to 255
Resolution 0.8125 amps per unit
Example: Setting of 255 =(255x0.8125)+150
= 357 amps
If you PM me your email address I can send you the T2 manual. Turns out the instructions for your handset are in there. Who knew? LOL

Thank you very much

So I’m guessing the setting range is gonna be

0 to 255

I’m guessing 0 will net you a Max amp draw of 150 and setting 255 will give you the full 357 Amps

That’s how I read it. Have never measured the current draw to verify.

My BMS has an amp meter on it so I am able to see how much current the car draws and I’ve seen 260 A at times so it seems that I am with in range

My BMS is rated at 300A. I haven’t had the courage to run the drive current through it. I only run charge through it. When I get back off of vacation I plan to start a supplemental dash display project to capture all of the key data I want to track. Drive current will be in scope as will temperatures, motor RPM and battery voltage. I will probably add elevation gain and loss eventually as well. One of the nice things with the lithium batteries is that most of the regen current actually goes back into the batteries. Lead acid can’t take the charge that fast so you lose most of it. That alone I believe adds notably to our range - especially in the hills where I run. I can monitor my voltage and the pack voltage rises notably on long descents.

Well just got back from Adjusting Down the Field Current and the Armature current. They were both turned up all the way. Max is setting 255

So I turned them both down to 225 and put some thermal grease on the back side of the controller and took it for a test ride. We noticed only slightly slower take off and that was it. Completely accepatable. So now we will just wait and see how she runs my gut tells me it’s gonna be just fine.

Thanks for your help

Glad you got it working. I wonder what changed? I’m assuming it had been running fine before. I wonder if the temp was truly running higher or if its just degradation of the sensor circuit. Have you run it in the hills to see if the lower current affects it there? I’d like to turn mine down because I don’t need to take off fast enough to smoke the tires (I already adjusted the ramp time) and I’d like to run it as low as I can because heat is the biggest enemy of electronics.

Great looking car. I love the blue.

I ran my high voltage cars as low as 180. No reason, it seemed fine.
Same reason I set every thing back to stock. Just because!

I think Overheat is a is a result of certain type of driving and hills and passengers. I have always overheated when I’m going real slow. Car runs cooler when your “On it” I sold the car and the new owner had the over heat issue 1 time and I figured it may come back so that’s when I decided to turn it down.

I’m wondering if lowering that would actually make it easier to hold a lower speed. My community has all 25MPH speed limits and I struggle to hold the pedal lightly enough to maintain that speed or slightly above. It literally is just off of creep mode to hold it there. Lowering the current might actually put 25MPH further into the pedal stroke which might be nice. I am playing with the Turf mode settings to limit the car to a true 25MPH for when my kids and guests are using the car. I don’t trust them with full power.
The challenge is that I live in the middle of a hill and my wife’s only ask was to be able to do 25MPH up the hill so I can’t jeopardize that. This is such a fun hobby!

With a magic magnet it’s switchable. Only limits speed.
You can add a key or hidden switch. I also experimented with rfid key. Only goes fast when key is near the gem.
Same would work on the forward switch. Cut p3 to limit to turf mode.

Another thing I’ve done is to “pad” the speed pot. I believe there are calculators online if you don’t want to do the math.
Pad it to have smaller affect on the bottom of throttle range. Of course replacing with a non-linear pot might be better.
Somewhere on here I posted some resistor values.

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Yes David’s RFID was cool. I tested it.
Here’s how it works when the RF ID Chip is present it allows the car to go to whatever speed you set it to let’s say (40mph) and when the RF ID Chip is not present the car we go to a lower setting let’s say (25 Mph)