How to test a used eBike

[thetimmy]

I purchased a used mongoose bicycle http://www.walmart.com/ip/26-Mongoose-Ledge-2.1-Men-s-Mountain-Bike/26999421
that had been fitted with this generic 1000W 48V ebike kit. http://www.amazon.com/Motorize-1000w-Electric-Bicycle-Conversion/dp/8805001546
The bike came with 4 SLA batteries http://www.amazon.com/UB12120-12V-12AH-BATTERY-VOLT/dp/B007QW7T2M/ref=pd_bxgy_468_text_y
that could not hold a charge, so he gave me a discount and I took it home and tested it with this http://www.amazon.com/Bhbuy-Electro-Scooter-Brushless-Controller/dp/B00MIONYH2
and the hub motor is working, the reason for the failure was that the three phase wires were melted together.
I need to test the controller http://www.amazon.com/Sunwin-Electric-Bicycle-Brushless-Controller/dp/B00DBM0WFC
but lack a 48V battery needed to power up the controller. I was wondering if I could purchase a 110VAC to 48VDC power adapter
http://www.amazon.com/automatic-sco...ie=UTF8&qid=1431609567&sr=8-1&keywords=48v+3A
To test the controller and possibly run the hub motor, but I’m not sure how many Amps the adapter would need to put out (linked model is 3A). I don’t plan on zipping up and down the street with a 1000ft extension cord, so I just need enough power to make sure the hub motor is working before I invest additional funds.
Any advice on how to proceed would be very welcome

 

[d8veh]

3A should be OK for testing with the wheel off the ground as long as you're gentle with the throttle. It'll draw about two amps at a steady high speed.

 

[dnmun]

if the phase wires have already melted and they are shorted then you should not power up the controller to it.

 

[thetimmy]

if the phase wires have already melted and they are shorted then you should not power up the controller to it.

The Phase wires were shorted when the plastic connectors that join the hub motor wires and controller wires melted together. The wires had no damage other than a bit of black discoloration, but the plastic connectors have to be replaced.

Does anyone have a recommendation on a 48V power supply I can use to power the hub motor and test the controller?

 

[dnmun]

you can test the controller without powering it up.

 

[thetimmy]

you can test the controller without powering it up.

That is excellent news, can you point me in the right direction for how to test it?

I have this device http://www.amazon.com/Bhbuy-Electro-Scooter-Brushless-Controller/dp/B00MIONYH2 and when I connected it to the controller (no power) I got no results from the tester.

 

[dnmun]

i don't know which links or where on justin's website to find them. i just use the diode tester on my DVM to test the output mosfets which is what is the risk from shorted outputs.

 

[thetimmy]

i don't know which links or where on justin's website to find them. i just use the diode tester on my DVM to test the output mosfets which is what is the risk from shorted outputs.

Are you referring to this post?
http://endless-sphere.com/forums/viewtopic.php?f=3&t=69441

 

[John in CR]

Get yourself an ebike tester. Easily test motor, controller, and hall sensors. Maybe the guy's charger is enough to power up the controller. The controller would be of little concern to me, as I'd want to install my own programmable one, or if on a strict budget, a cheapie. I'd only worry about the motor, which is where the tester is worth its price in just the first use.

 

[Ykick]

I have this device http://www.amazon.com/Bhbuy-Electro-Scooter-Brushless-Controller/dp/B00MIONYH2 and when I connected it to the controller (no power) I got no results from the tester.

Sorry, dunno how to tell you how to use a tester, I've never used one.

Usually get along fine with the info here:
http://www.ebikes.ca/learn/troubleshooting.html

and of course searching/reading ES.

 

[teklektik]

In a recent post:
Links to doc for that tester and links to other relevant test procedures.

 

[dogman dan]

Unplug the controller from the wheel. Spin it. Is it really hard to turn? If so, your phase wires are shorted. You can deliberately, with out damaging anything, touch two of the phase wires from the motor together. Then it will be hard to turn.

Now without powering up, connect the phase wires into the controller. Is the wheel still easy to spin? If it gets really hard to turn, then the controller is blown at the fets. Typically, if the controller is on while phases get shorted, then they could blow the controller.

If it passes that test, power it up somehow and try it. Ebike testers are great, not expensive, or very hard to use. But if it won't run, I'd just grab a cheap controller off ebay and run with that. Look for one with self study, or self learn capability, so it will be easy to get it running.

 

[thetimmy]

Unplug the controller from the wheel. Spin it. Is it really hard to turn? If so, your phase wires are shorted. You can deliberately, with out damaging anything, touch two of the phase wires from the motor together. Then it will be hard to turn.

Now without powering up, connect the phase wires into the controller. Is the wheel still easy to spin? If it gets really hard to turn, then the controller is blown at the fets. Typically, if the controller is on while phases get shorted, then they could blow the controller.

If it passes that test, power it up somehow and try it. Ebike testers are great, not expensive, or very hard to use. But if it won't run, I'd just grab a cheap controller off ebay and run with that. Look for one with self study, or self learn capability, so it will be easy to get it running.

The wheel spins freely when the 3 phase wires are not touching (shorted) and comes to a quick stop when I touch them together. There is some corrosion and scorching on the connectors.

The wheel spins freely when the 3 phase wires are connected to the controller, just as it did when it was not connected.

I purchased the following 115VAC to 48VDC power supply, http://www.ebay.com/itm/like/321687335936?lpid=82&chn=ps, this should provide 3A which I hope should be enough to get the wheel spinning.

I would like to thank all of you for your help.

 

[thetimmy]

The 48V 3A AC to DC power supply arrived from China this weekend. When the throttle is depressed fully the motor would start and stop quickly, but when the throttle was only lightly depressed the wheel spun continuously. I'm fairly certain that this is a result of the 48V power supply only being able to output 3A which can run the motor at low speed only.

Thank you all for your help. My next step is to buy a battery.

 

[dnmun]

that power supply is not designed to charge a 48V lifepo4 battery.

 

[thetimmy]

that power supply is not designed to charge a 48V lifepo4 battery.

You are correct, this power supply was used to substitute for a 48V SLA battery that was dead, it powered the controller and allowed me to test all other functionality for under $20 shipped.