How to check controller voltage ratings

[RichardT]

Hi Experts

I have a controller that i was sold to be used for 36V hub motor.
I plugged it into the 36v hub motor and powered it up with 36v battery pack. It does not run.
I changed the battery pack to 48v, it runs!

How can i check for myself what is the ratings of the controller i bought? I suspect the label of the controller is wrong.
What is there to measure ?

Or is my hub motor set to run on 48v instead of 36v by eg. computer interface programs? The hub motor is engraved with "36v".

Thanks.
regards
Richard T

 

[Nobuo]

Your 36V battery was fully charged?

The curious thing is that if the 36V was full charged (supposed it is a lithium battery) the max voltage is 42V, so it would even work probably on a 48V controller. So that's not enough information. COuld you take voltage measurements on the discharge connector of the 36V battery?

You can always open it and check voltage parameters. You have any idea of the controller brand?

 

[dogman dan]

Sounds like the controller is programmed for a 42v lvc. or something like that, for 48v use.

But I'd also have a good look at the plug on the 36v batt.

 

[dnmun]

no info on the voltage of the 36V battery or if it is shut off at the LVC.

 

[d8veh]

We need a lot more specific information on what you've got. Which controller is it? What is the actual measured voltage from the 36v battery?

Did you check that you got the right polarity on your 36v battery?

The motor doesn't care about the voltage. Your problem is between the controller and battery.

 

[dogman dan]

Could easily be entirely a battery, or battery wires problem. As always, there is much info they don't tell us.

 

[RichardT]

Hello Friends!

Thank you so much for your responses!

I truely appreciate your comments.

The 36v battery pack is at least 36v. So, I doubt its a battery pack voltage level issue.

I also believe its due to software programming to limit the controller to operate at 48v as commented by one of our experts here.

I am still trying to find out what to look for to tell what is the voltage the controller is set for. Can the Mosfets tell me anything?

Thanks all.

 

[d8veh]

There's thousands of different controllers. You still haven't shown us which one you have. How can we help you then?

 

[brumbrum]

Its pretty obvious that the controller has been programmed to have a low voltage cut-off higher than 36 volts, hence there is not enough voltage in your battery. An LVC is a safety feature on a controller to stop you running the battery down too low.
If you have a '36v' lithium battery it will be around 42v when fully charged, so if this battery does not make your motor run then the low voltage cut-off on your controller must be somewhere between 42 and 48 volts.

Or, as said above, check the spades/pins at the end of the 36v battery connector with a mulimeter to check that the battery is pumping out its power. Also check that when you push the battery connector into the controller connector that the pins/spades are not being pushed backwards and not connecting together properly.

 

[dnmun]

no, not obvious, we know nothing.

 

[brumbrum]

no, not obvious, we know nothing.

Fair enough, some photos would be helpful, but it does sound like the OP is on a steep learning curve.

 

[RichardT]

Its pretty obvious that the controller has been programmed to have a low voltage cut-off higher than 36 volts, hence there is not enough voltage in your battery. An LVC is a safety feature on a controller to stop you running the battery down too low.
If you have a '36v' lithium battery it will be around 42v when fully charged, so if this battery does not make your motor run then the low voltage cut-off on your controller must be somewhere between 42 and 48 volts.

Or, as said above, check the spades/pins at the end of the 36v battery connector with a mulimeter to check that the battery is pumping out its power. Also check that when you push the battery connector into the controller connector that the pins/spades are not being pushed backwards and not connecting together properly.

Hi Brumbrum
Thanks for your comments.

Yes, its seems to be due to LVC.

I used my 36v battery charger to directly power the controller and motor runs!
The charger gives about 42v.
At that time when i tested with my battery pack, the voltage was 41v.

So, seems clear that the controller was only able to support greater than 41 volts despite the fact that the controller label says its a 36v/48v compatible controller. I not sure what does 'AHT' mean , as its written on the label shown in the attached picture.

So far, i yet to understand how to check a controller to tell, apart from the labelling which could be wrong, what voltage it is designed to run on.

Thanks for reading.

Regards
Richard T

 

[RichardT]

There's thousands of different controllers. You still haven't shown us which one you have. How can we help you then?

Hi D8veh

I have uploaded the photo. Thanks.

 

[RichardT]

Your 36V battery was fully charged?

The curious thing is that if the 36V was full charged (supposed it is a lithium battery) the max voltage is 42V, so it would even work probably on a 48V controller. So that's not enough information. COuld you take voltage measurements on the discharge connector of the 36V battery?

You can always open it and check voltage parameters. You have any idea of the controller brand?

Hi Nobuo

Could you kindly elaborate more on the voltage parameters that can be checked by opening the controller case?

Thanks very much.

 

[Nobuo]

The caps should be 63Vmax or 60Vmax on a 48V controller (or a 36V & 48V controller). For a 36V controller the caps should be 50Vmax.

If you can take a photo of the main board just after opening the aluminium case, share to visual check

 

[docw009]

I cannot read chinese, but that looks like a multi-use 36volt/48volt controller with a 31/42 volt low voltage cutoff. They might set a jumper or add a part to make it 36 or 48 volts, and then they mark it on the outside. In this case, either the OP or the factory scratched a circle around the 48 volts on the controller label.

OK, Who did the circle. Was it RichardT or the factory?