Current location for King Malu

Monday 20 May 2013

More testing

Today we ran the motor for about 4 hours  - running it between 1,000 and 1,500 RPM. We were careful not to push it too much as we still didn't have the small gear wheel locked in place. When we get it drilled and tapped, and also extra washers made for the large gear (the side cheeks are different on the large gear, so we need extra washers for both front and back) we'll do further tests pushing it harder. For these tests the motor was running at about 34C and the controller at about 30C.

One thing that took longer yesterday and Friday to install was the new relay PCB. There were a number is reasons:

I found that that Curtis controller uses positive common for the PWM drives (undocumented) which is somewhat strange and meant all the relays initially didn't work because the diodes were all the wrong way round!

Second problem was that the automotive relays behaved differently from the new PCB relays - the automotive didn't worry about the PWM but the PCB ones just buzzed and didn't make contact. Researching this online I found that the automotive ones worked more by luck than judgement and all relays should have a capacitor across them when connected to PWM to smooth out the pulses. I have it now working! In the process found that the Curtis controller doesn't like highly capacitive loads - which is also undocumented.

See all posts about PropEL Electric Drive.

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