Test 36V DD Motor without controller ?

[qwerkus]

Hello,

I got a motor from a defective ebike, and would like to know if it works. It's a DD Motor with 3 wires (big red, big black, small yellow) - no hall lines as far as I cann tell.. Unfortunately, all I got left is a 36V charger and usual electrical tools (Voltmeter). Does anyone know a quick / cheap way to check if the motor is still working ?

Thank you for your help,

qwerkus

 

[MadRhino]

You can spin it and see if it does generate current.

You can test the impedance between phase wires.

You can test continuity between each phase and the axle to see if it is shorted.

You can test the hall sensors, if it has some.

You can buy an Ebike tester on Ebay for peanuts, or a small controller for very cheap.

 

[qwerkus]

Thank you for your quick reply.

1. works - quite difficult to turn an unlaced motor, but I definitely measure a current spike

2. Not sure how to do that one

3. also works: no short so far

4. no hall sensors

5. I'd like to avoid investing anymore in that part. It's only to know if I'd better scrap it, or give it away.
Strange thing is that the manufacturers pages says there is an integrated controller. How do I test that one?

 

[amberwolf]

If there's 3 wires, and continuity measures short between all of them (and nothing else) then there's no controller--it's just the bare phase wires for a 3phase brushless motor.

With two large wires and one small, it could be a brushed motor, in which case there's a short between the two large. The small may have a resistance to one of the others if it's a temperature sensor.

If the two large are power for teh controller, then it's possible the third wire is a throttle input for a potentiometer from that wire to ground (or that wire to power, though that's unlikely).

You'd have to check with the manufacturer for what voltage the power would be for. If you exceed it, it might eithe rnot work, or it might burn out (if it isn't already).

Or take the cover off and look inside.

It's also possible it's missing some wires, that have been yanked out of the axle or cut off at the axle or inside it.

 

[MadRhino]

If it has an integrated controller, it has 2 power wires (usually black and red) and a bunch of small wires with connectors for E-brakes, throttle and/or PAS, maybe a display connector...

Post a pic, that would help

 

[qwerkus]

Thank you for your help. No short between the 2 large wires. Manufacturer's docu seems quite tricky to find. It's a go swissdrive, and they only do oem motors. Tried to contact them without success so far. Attached, 2 pictures:

EDIT: found the documention from the ebike company. It reads: 36V / 250W brushless dc motor. No mention of an integrated controller, nor does it explain what the yellow wire is for.

 

[Buk___]

36V / 250W brushless dc motor. No mention of an integrated controller, nor does it explain what the yellow wire is for.

[img=http://www.go-swissdrive.com/uploads/pics/gsd_head_unternehmen_03.jpg]This image from their website[/img] shows an integrated controller.

They also show a color lcd controller with lots of buttons and a throttle, which may mean the third wire is some kind of 1 wire comms bus between that contol unit and the controller.

 

[fechter]

It would seem to have an integral controller. Double check the yellow wire and make sure it's not really a cable with several smaller wires inside. Normally there would be at least 3 wires for a throttle connection. The big black and red wires get 36v, and throttle goes to the yellow wire somehow. You might be able to test it using the output from the charger, but that would barely have enough current to turn the motor.

 

[Buk___]

It would seem to have an integral controller. Double check the yellow wire and make sure it's not really a cable with several smaller wires inside. Normally there would be at least 3 wires for a throttle connection. The big black and red wires get 36v, and throttle goes to the yellow wire somehow. You might be able to test it using the output from the charger, but that would barely have enough current to turn the motor.

Looking closely at the OPs first picture above, there might be two cores in the yellow cable, but given the amount of functionality available from the display, 3 regen levels, 5 PAS, motor temp etc. it has to be a bus of some kind.

 

[MadRhino]

It is a standard can-bus. The display has the function of dispatching the PAS and ebrake signals to the controller, along with managing assist levels.

It had this display

The newer display can replace it, and has bluetooth connectivity for smartphones.

It is the motor that was powering the Specialized Turbo.

Buying the genuine missing parts to make it work would be expansive. I suggest to bypass the integrated controller and make it work as a standard motor with a small chinese controller, a common PAS or throttle, and a dolphin battery.

 

[qwerkus]

Thank you for your replies. I guess I'll need to open the motor to be sure. Probably going to be a mess, since it's looks like bathing in oil. Also, those screenshots and infos you guys found seem to concern recent version of the motor. The one I have is from 2011. Not sure all the fancy high tech stuff would apply.

 

[fechter]

Oil?
I'll be interested to see if it really is oil filled. I guess loosen the screws and put it over a bucket before prying the cover off.
It should be a pretty good motor with an external controller. The hall sensor wiring might be a bit of a pain, but hopefully the wires are easily accessible.

 

[qwerkus]

Oil?
I'll be interested to see if it really is oil filled. I guess loosen the screws and put it over a bucket before prying the cover off.
It should be a pretty good motor with an external controller. The hall sensor wiring might be a bit of a pain, but hopefully the wires are easily accessible.

Thanks for the input fetcher. In the manual, there is mention of "oil maintenance" via the red cap. I might as well change the oil when at it. Do you know which one would work ? Afaik there was a thread about oils, but I can't find it anymore...

 

[MadRhino]

Many are adding oil inside hub motors, to help shedding the heat when they are fed high power and/or abused in steep climbing. This started with various kind of oil type and grade, and finally turned to experiences leading to the best solution for heat dispersion: Ferrofluid.

That is what you have to search on ES. Justin had published the results of his tests, and that is what most are using now.