|
| experienced, such as a rolling of |
|
| numbers, or |
|
| first check for a display circuit |
|
| caused by a voltage |
|
| spike or surge in the incoming power |
|
| lines. To eliminate this condition, |
|
| remove power from the time/temp |
|
| display by shutting off the main fan |
|
| switch for 15 seconds. This should |
|
| eliminate the problem. If this does not |
|
| solve the problem, it may becoming in |
|
| through the Commercial power lines. |
|
| Suggest that customer contact their |
|
| power company for evaluation. |
Temp display inaccurate, | Time/Temp Display | Perform the power supply check, the |
erratic, or inoperative |
| thermistor probe check, and then |
|
| perform the time/temp simulator test. |
|
| Refer to Section D for instructions. |
|
| Remember, when using the time/temp |
|
| simulator, remove all leads from the |
|
| back of the time/temp display except the |
|
| 3 power leads. |
|
| After completion of the test, and if re- |
|
| installing time/temp display back in the |
|
| oven, the dip switches must be reset for |
|
| oven operation, and the time/temp |
|
| display must be recalibrated. If |
|
| readings are not achieved, replace |
|
| display. |
Time Display inaccurate, |
| Perform all checks as in the above |
erratic, or inoperative |
| evaluation. If the time check is okay, |
|
| refer to the next section. |
| Conveyor Drive | Check to see if the conveyor drive |
| (Stepper) Motor | (stepper) motor is running. If motor |
|
| is not running, refer to “Conveyor will |
|
| not run” on Page 45. |
| Magnet | Check to insure that the magnet |
|
| (cemented to shaft of conveyor drive |
|
| [stepper] motor) has not been damaged, |
|
| or come loose from motor shaft. |
|
| Replace as needed. |
| Hall Effect Sensor | Check for any physical damage to Hall |
|
| Effect sensor (mounted on conveyor |
|
| drive [stepper] motor). Check all |
|
| wiring and connections for damage. |
|
| If the motor is running, the magnet is |
|
| in place, but the display |
|
| the Hall Effect Sensor may be defective |
|
| or improperly connected. |
| Conveyor Drive | Check all connections for tightness or |
| (Stepper Control) | proper location and check all wiring |
|
| for visible damage. Replace as needed. |
|
| If there is still no time display and all |
|
| the above have checked out, replace the |
|
| stepper control. |
46 |
| Impinger II - 1100 Series Service Manual - International |