Q85 250W motor current load issue

Dear All,


I got the Cute 85 250W 1,6kg hub motor (model G-M85F from ebike-bmsbattery.com/) and after testing it I got stranges behaviors. I did my test with the wheel in the air (in free wheeling mode) and the Lyen 6FET controller. From the PDF specs (from ecitypower.com I think it's the same motor) the curve show the nominal load condition at ~6A for 36V and a low speed (it seems, in fact I dont know right value ). In fact I got 14A load for 28V in nominal condition and I sized my battery for 7A nominal. What is the issue here?
http://www.ecitypower.com/pdf/Q-F-85SX-Specification.pdf

I'm wondering if the specification are correct or If my motor is broken?

Cheers,
olivier

14A at 28V seems more like a peak load than nominal. How exactly did you measure the current and how exactly did you load the motor? If a motor runs smoothly without cogging or other strange noise/drag, you should be OK.

I put a watt-meter on the battery.
Last night I fixed the issue and I learned life. I inverted two phases (yellow and green) not because my eyes are blured but the colors are wrong

The current load in freewheeling is about 2A, really better.

cheers,
olivier

Hi,

Did you buy the bare motor or their "ebike kit" laced into wheel?

Would you mind weighing the motor? While BMS battery specs says 1.6kg, rumours are that it is a bit heavier at about 2kg. I'm curious to know the weight.

Also if already laced, please let us know rim type and spoke gauge so we can subtract that out.

Thanks,
Martin

Hi Jag,

I bought the motor without the wheel and spoke, unfortunately I did not weight the motor and now the wheel has been setup. I can do the check, I have to find a weighing scale then, minus:
- bionx wheel (dont find specs for weight?)
- 2x36 (.01Kg) spokes from (http://ebike-bmsbattery.com/index.php?url=dispro.php%3Fid%3D72)
- one tire (I will check the weigth)

oe

I have Q85 front motor without rim/spokes. The weight on my IKEA scale is 1.72 kg. This is the narrow unit for rim brakes only.

evaleto said:

I put a watt-meter on the battery.
Last night I fixed the issue and I learned life. I inverted two phases (yellow and green) not because my eyes are blured but the colors are wrong

The current load in freewheeling is about 2A, really better.

cheers,
olivier

Click to expand...

I recently bought this motor and laced it into a 700C rim, the no-load current at 40V nominal was 0.7A on my Turnigy WattMeter.

The no load current from the battery would normally be less than 1A. If OP is getting 2A, something is wrong - probably inaccurate wattmeter reading. He should do the reset calibration procedure on the watt-meter if it has one just to make sure.