Hi Ronan,
More information is requred to make suggestions. First what type of motor is it ? (Permenant magnet, shunt wound. or series wound (Universal) ?) Second what is the voltage rating of the motor and the power rating ? (HP, amps, or watts) Third Is the board powered directly from the mains (230 or 415 volts) or via a transformer. Other useful information would be is it a standard tom senior fitting ? Is it one of the the propietry add on power feeds or is it a home made feed unit ?

Les.

If, as you say, there's 'copious smoke' when operating, could you not just run the motor with the cover removed from the control board to see where the smoke is coming from?

Hi Murray,
I agree with you that if the fault was bad enough to produce smoke then I would expect the board to be marked. I suspect that the photo may have been taken some time ago before the fault occured as Ronan has a number of pictures of the mill in his album. It would have been wise for him to investigate the cause of the smoke when it occured.  I found a site that claims to have a schematic but they want an email address and I do not trust sites like that.

Les.

Edited By Les Jones 1 on 24/03/2015 16:09:22

Hi

There is a little more information here but may not be too helpful, mainly setting up etc of this family of controllers.

Cheers

Martin

Ronan,

if you read the label again…….the field winding is 210v dc and is rated to draw 0.18 A, the armature is depicted below…….

HTH…….

Hi Ronan,
Before replacing the board I suggest that you check that the motor is OK first. Check that the field winding resistance is about 1200 ohms (210/0.18 = 1167) Check that the brushes look OK Check the resistance between the armature connections and turn the shaft a few degrees at a time. The resistance should be about the same in all positions of the shaft and much less than the field resistance. (I would guess is should be less than 50 ohms) If these readings are as expected and you have a DC power supply of between about 50 and 150 volts try the motor on this. (Connect the field and armature in parallel to the supply.) If the motor runs OK like this then the fault must be the board. If you cannot obtain (Or repair) the original board then a KBIC-240 board would probably work, There is one of these on ebay in the UK on sale at the moment and several on sale in the US.

Les.

Hi Ronan,
Electrolytic capacitors are prone to fail with high internal resistance particularly if they are handling high ripple currents. If you have access to an ESR meter (Effective series resistance) it is worth using it to test the capacitors in circuit. I was under the impression that the table drive was no longer working which is why I suggested testing the motor, If it is still working then the motor is probably OK and you should be able to see the source of the smoke as Gordon suggests.

Les.