Hi guys, I'm hoping someone could shed some light before I bite the bullet and buy a new circuit board.

I have a Proform premier 900 treadmill, with a 3hp motor and a MC2100ELS 18W-2Y controller. Everything looks to be connected correctly, all earth's are tight etc.

As soon as I switch it on, the motor fires for a second then the breaker on the house trips (it worked perfectly for a long time, this is a recent fault). If I disconnect the power to the motor, the screen on the treadmill lights up and works, however the red LED on the control board does not light up. I removed the motor and bench tested that on a 12V battery, and that seemed to work fine. I connected the motor back to the treadmill but removed the belt so there was nothing dragging it down, and that tripped the breaker. I also tried disconnecting the plug to the treadmill screen/controls, but the motor will still fire then trip.

I'm quite handy but I'm in no way an expert when it comes to diagnostics, is anybody able to shed some light on this please? Much appreciated!

 

how do you test 3hp motor on a 12V battery?

 

It looks as though one of the semiconductors for for the motor mounted on the HS is defective.
It is best to trouble shoot the MC2100 on the bench , you do however require a 20hz signal to achieve any motormovement.

 

tripping fuse/breaker tells you that current is too large. motor may be cooked. once the insulation is degraded you will have higher current draw.

 

how do you test 3hp motor on a 12V battery?

Its a good initial test for these motors, but it is rarely a motor problem.

 

@Shalsey Do you have the reverse-engineered print for these boards?
There is one here if you search, covers most versions, in principle.
Replace the motor with a 100w lamp, temporarily.

 

@Shalsey Do you have the reverse-engineered print for these boards?
There is one here if you search, covers most versions, in principle.
Replace the motor with a 100w lamp, temporarily.

Thanks for the advice! I don't have the print but I will take a look

 

See my post #8 here. the last one is the schematic.
Https://forum.allaboutcircuits.com/...readmill-stopped-working.147032/#post-1253371

 

@Shalsey Do you have the reverse-engineered print for these boards?
There is one here if you search, covers most versions, in principle.
Replace the motor with a 100w lamp, temporarily.

How 100w lamp instead of 3 phase motor?

 

No 1 they do not use a 3ph motor, at least on all these models.
The motor used is a 1.5hp to 3 HP DC brushed

 

No 1 they do not use a 3ph motor, at least on all these models.
The motor used is a 1.5hp to 3 HP DC brushed

I am sorry, I read wrong, instead of reading horse power I’ve read 3 phase
Now it’s clear for me
Thanks