motor controller

[Gord]

Maybe someone is more familiar with this than I am: I have a treadmill motor control PCB and the resistor that is connected in series with a relay and the rectifier is burned up. I am trying to determine a value for replacement without a schematic. Any ideas? I can describe circuit in more detail.

[ikalogic]

a good close up picture would be very helpful

[Gord]

the relays are removed; the red box outlines burned resistor location; 120 VAC passes through contacts, then resistor on to rectifier. The second relay would switch on to then bypass resistor. This seems to be switching through 120 VAC to rectifier to charge up 1500uf cap to then run 3hp treadmill motor. The resistor acts as spark suppression or current limiter? Thanks for help!

Here is a picture-I have ful view too;can upload.

samsungcam 042.jpg (161.82 KB) Viewed 609 times

[Gord]

Maybe better with arrows?

samsungcam 043.jpg (162.11 KB) Viewed 603 times

[ikalogic]

what's written on the white component next to the arrow? ..?.. 47...?

[Gord]

sorry, wasn't sure which arrow-see next

[Gord]

to the left of left most arrow? that is 47n K 275V~

[ikalogic]

hhmmm i am quite confused... I really wanna help, can you take really good close up picture? one where i can zoom in and see the text on the components for my self?

[Gord]

hope these are better

more pics

[Gord]

closer with relays set back in

closer

[ikalogic]

Here is what i would do, i would try a 1K resistor (1 W rating), if nothing happens decrease its value to minimum 220 Ohm.

If it burned up, it probably means the manufacturer (china?) used too low power rating resistors.

good luck

[Gord]

Tried 1K 1W resistor all is working. Treadmill seems slow or lacking power at slow speeds-it slows down appreciably when i step on it at slow speeds. The belt seems to be lubed properly. Would the 1K be resisting too much at slower speeds-I guess i could go down to 220ohm and check difference. Thank you for help! Gordon.

[ikalogic]

Tried 1K 1W resistor all is working. Treadmill seems slow or lacking power at slow speeds-it slows down appreciably when i step on it at slow speeds. The belt seems to be lubed properly. Would the 1K be resisting too much at slower speeds-I guess i could go down to 220ohm and check difference. Thank you for help! Gordon.

Great news... yes but try first 470 or even more.... Don't every try to increase its power as compared to what it was before.. if one component burned up, it means many others can follow, so we don't want to push it to the limits... got my point?