Conveyor will not run | Fan Switch | Check continuity between switch terminals. Replace |
S/N 4000480 and Below |
| as needed. |
| Conveyor Control | Check for supply voltage at primary of transformer. If |
| Transformer | no voltage is present, trace wiring back to fan switch. |
|
| Check for 24VAC at transformer secondary. If no |
|
| voltage is present, replace transformer. |
| Speed Adjustment | This is a 5K ohm potentiometer. WITH POWER OFF: |
| Potentiometer | Remove the leads from the motor control board at |
|
| terminals P1, P2, P3. With a digital meter, check the |
|
| ohm reading across the red and black leads. This |
|
| reading should be 5K ohms (± 10%) as the pot. is |
|
| rotated from low to high. Place meter leads on red |
|
| and white lead. Rotating the pot. slowly from low to |
|
| high, the meter reading should show an even |
|
| transition from 0 to 5K ohms (± 10%). There should |
|
| be no dead or open spots throughout the rotation of |
|
| the pot. Check all three (3) leads to ground. There |
|
| should be no continuity to ground. If any of the above |
|
| checks fail, replace the pot. |
| Conveyor Control Board | Check for 24 VAC input to conveyor control. If no |
|
| voltage is present, trace wiring back to transformer. If |
|
| voltage is present at L1 and L2, check for D.C. output |
|
| at terminals A+ and |
|
| but no D.C. voltage output, replace conveyor control |
|
| board. |
| Conveyor Gear Motor | If there is D.C. voltage output from the conveyor |
|
| control, but the motor does not run, check the mini- |
|
| breaker (0.7 Amp). Check motor leads for opens, |
|
| shorts or continuity to ground. If motor fails above |
|
| test, replace motor. |
| Conveyor | Check conveyor drive coupling to be sure that it is |
|
| tight. Also check to see that coupling is engaged with |
|
| conveyor drive shaft. Check for any mechanical |
|
| misalignment or improper adjustment, also check for |
|
| worn bearings. A conveyor belt that is too tight will |
|
| cause excessive bearing wear and sometimes- |
|
| irregular speed. |
Conveyor speed | Power Supply | Check for steady supply voltage to oven. If voltage is |
varying or intermittent |
| unsteady, contact power company. |
| Transformer | Check for steady A.C. voltage output from transformer |
|
| and replace as needed. |
| Conveyor Control | Check for steady D.C. voltage output from conveyor |
|
| control. If D.C. voltage output is unsteady, check |
|
| conveyor potentiometer (see "Speed Adjustment |
|
| Potentiometer" under Conveyor will not run). If the |
|
| potentiometer checks good, and the D.C. voltage is |
|
| unsteady, replace conveyor control. |
| D.C. Gearmotor | Check motor brushes for excessive arching and/or |
|
| unusual wear. Replace brushes or gearmotor as |
|
| needed. |
November 1999 | 33 | COUNTER TOP IMPINGER |