Jump to content

DKS 550-Wrong Rack Motor Speed


Recommended Posts

There are several reasons for this message.

Mechanical problem in the racks, technical box, dryer, usually then there is overtorque error also.

Another issue is that one pot is not adjusted properly and system signal wrong speed too early.

Check nominal voltage near motor (for 129Hz speed it should be about 8.5V-9.5V).

Check rack motor speed on the screen (it should not varied too much (+/- 2Hz)

Also I had situation that mechanically everything was OK, and speed in Hz were also about 129Hz, but on the end motor brushes were worn out, and replacing only the brushes fixed the problem (rotor was also damaged).

Link to comment
Share on other sites


Thanks for the response. Last night I checked the voltages and connections it's ok.

The screen displays 129Hz and it drops then the error occur.

Mechanical problem in the racks was my first suspect but I manually checked it seems ok.

When I remove the motor for inspection, i saw some carbon debris coming from it.

Sir, what do you mean by this "Another issue is that one pot is not adjusted properly and system signal wrong speed too early" sorry, i'm quite new to this machine.

thanks anew.


Link to comment
Share on other sites

There is one trimmer for adjusting the nominal current for the motor. Also there is measuring spot near by which should be about 5V, if not then this trimmer is used to adjust it, I can check the trimmer number by Monday.

But If you have 129Hz, is it stable ?

Beside checking the rack, try to turn main shaft to verify that it turn easily, maybe you have mechanical problems between main shaft and racks, there are 5 small shafts inside black plastic box, which are connecting main shaft and the racks.

Also check the bearings on the main shaft, if there is bad sound coming when shaft is turning, then the bearings are worn.

If you have somebody to check the motor and the brushes inside that would be worth to check ?

If motor stops, try to knock it and if then starts to turn then 99% the problem is the brushes inside the motor.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...