| Speed adjustment | This is a 0 to 10K ohm, 1 turn potentiometer. |
| potentiometer | With power off, remove the black and white |
|
| pot. leads from the motor control board at |
|
| terminals P1 and P2. Place the meter leads on |
|
| the black and white pot. leads. Rotating the |
|
| pot. slowly, from low to high, the meter reading |
|
| should show an even transition from 0 to 10K |
|
| ohms ± 5%. There should be no dead or open |
|
| spots throughout the rotation of the |
|
| potentiometer. Check both pot. leads to |
|
| ground. There should be no continuity to |
|
| ground. If any of the above checks fail, replace |
|
| the potentiometer. |
| Magnet | Check to insure that the magnet (cemented to |
|
| shaft of conveyor drive motor) has not been |
|
| damaged, or come loose from the motor shaft. |
|
| |
| Hall effect sensor | Check for any physical damage to hall effect |
|
| sensor (mounted on conveyor drive motor). |
|
| Check all wiring and connections for damage. |
|
| Replace as needed. |
| Hall effect sensor cable | Check continuity through the wires in the cable. |
|
| Check all wiring and connections for visible |
|
| damage. Replace as needed. |
| DC motor control board | With motor running, measure DC voltage |
|
| across the red wire and black wire in the hall |
|
| effect cable (all wires must be connected |
|
| during this test). Voltage reading should be |
|
| approx. 12VDC and steady. If this reading is |
|
| not achieved, replace DC motor control board. |
| Hall effect sensor | With the motor running at maximum speed, |
|
| measure the frequency across the white wire |
|
| and the black wire in the hall effect cable (all |
|
| wires must be connected during this test). |
|
| Reading should be approx. 327 Hz. And |
|
| steady. If there is no reading, replace hall effect |
|
| sensor. If the reading is unsteady, calibrate the |
|
| DC motor control board. |
Temperature display | Display transformer | Measure the transformer primary for supply |
inoperative |
| voltage input. If voltage is not present, trace |
|
| wiring back to the oven fan switch. Measure |
|
| the secondary output, which will normally be |
|
| |
|
| should be |
|
| should be ½ the voltage reading |
|
| above secondary readings are not achieved, |
|
| replace transformer. |
| Temperature display | If proper voltage is present at terminals 1,2 and |
|
| 3 on temperature display, but the display is not |
|
| lighted, recheck all connections for tightness. If |
|
| temperature display is still not operating, |
|
| replace the temperature display. |
Temperature display | Thermocouple | Place the thermocouple of a pyrometer into the |
inaccurate, or erratic |
| center of the top finger. The pyrometer will |
|
| indicate oven temperature. Measure DC |
|
| millivolts of thermocouple at the temperature |
|
| display. See thermocouple chart in “Removal |
|
| and Installation” section for proper readings. |
|
| Replace thermocouple if proper readings are |
|
| not achieved. If readings are correct on the |
|
| thermocouple, recalibrate or replace |
14 | Impinger II – |