Facebook
Google
GitHub
Linkedin
Hi folks,
I have a HealthRider treadmill with an MC2100ELS-18W controller. After many years of faithful service, it started slowing down and then stopped during an inclined walk at 4 km/h. I cycled the power and commanded 4 km/h again, but there was no belt movement and I detected a burning smell.
A physical examination revealed a fried connector in one of the cables connecting the drive motor to the board. I replaced the connector and re-tested, and a 40 A circuit breaker for the building tripped the instant the belt was supposed to start moving. I didn't see that coming.
Further examination revealed a collector/emitter short on the IGBT. While I was waiting for a replacement IGBT, I tested the motor by running it from a 24 V bench power supply. Under no-load conditions it drew 4 amps, and I ran it for 20 minutes without incident. The motor was still cool to the touch afterwards.
With the IGBT replaced (and also, for good measure, the SCR), I powered up the treadmill and commanded a 2 km/h belt movement. It started as expected, ran as expected for around 10 to 15 seconds (I didn't measure the exact time, but it's completely consistent), and then the motor cuts out/progressively slows. When the belt speed has dropped to around 1/4 (keeping in mind that this is now under no-load conditions), it then accelerates back up to the commanded speed again. Rinse and repeat.
Commanding 4 km/h resulted in a faster belt movement, but the same cutout/slow-down-then-resume pattern. I've measured the HV rail and can confirm that it's not falling under load. I've tested the tacho sensor with a multimeter and confirmed that it's opening and closing as expected.
Although it would be easier to just replace the controller, the "technician in me" (I used to calibrate and repair electronic test equipment for the military in the early 1980s) would like to see if I can identify and fix the fault. I have full workshop facilities (oscilloscopes, power supplies, etc.) - not as sharp as I used to be but hopefully able to get to the bottom of this.
I've downloaded the 2nd revision of the excellent reverse-engineered schematic created by another member, but I'm just wondering if someone would be so kind as to point me in the right direction as to which sub-circuit I could start looking at first, and/or offer some guidance on what might be going on so I've at least got some kind of mental baseline when I start scoping the various paths.
Many thanks in advance.
Cheers,
Colin
I have a HealthRider treadmill with an MC2100ELS-18W controller. After many years of faithful service, it started slowing down and then stopped during an inclined walk at 4 km/h. I cycled the power and commanded 4 km/h again, but there was no belt movement and I detected a burning smell.
A physical examination revealed a fried connector in one of the cables connecting the drive motor to the board. I replaced the connector and re-tested, and a 40 A circuit breaker for the building tripped the instant the belt was supposed to start moving. I didn't see that coming.
Further examination revealed a collector/emitter short on the IGBT. While I was waiting for a replacement IGBT, I tested the motor by running it from a 24 V bench power supply. Under no-load conditions it drew 4 amps, and I ran it for 20 minutes without incident. The motor was still cool to the touch afterwards.
With the IGBT replaced (and also, for good measure, the SCR), I powered up the treadmill and commanded a 2 km/h belt movement. It started as expected, ran as expected for around 10 to 15 seconds (I didn't measure the exact time, but it's completely consistent), and then the motor cuts out/progressively slows. When the belt speed has dropped to around 1/4 (keeping in mind that this is now under no-load conditions), it then accelerates back up to the commanded speed again. Rinse and repeat.
Commanding 4 km/h resulted in a faster belt movement, but the same cutout/slow-down-then-resume pattern. I've measured the HV rail and can confirm that it's not falling under load. I've tested the tacho sensor with a multimeter and confirmed that it's opening and closing as expected.
Although it would be easier to just replace the controller, the "technician in me" (I used to calibrate and repair electronic test equipment for the military in the early 1980s) would like to see if I can identify and fix the fault. I have full workshop facilities (oscilloscopes, power supplies, etc.) - not as sharp as I used to be but hopefully able to get to the bottom of this.
I've downloaded the 2nd revision of the excellent reverse-engineered schematic created by another member, but I'm just wondering if someone would be so kind as to point me in the right direction as to which sub-circuit I could start looking at first, and/or offer some guidance on what might be going on so I've at least got some kind of mental baseline when I start scoping the various paths.
Many thanks in advance.
Cheers,
Colin
