Ametek Thermox Series 2000 WDG-IV, User Manual

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7-6 | Thermox Series 2000 WDG-IV / IVC / IVCM
Thermocouple Replacement
The tip of the thermocouple is positioned in the furnace so that it is
near, but not touching, the cell housing or the furnace heater coil.
Use Figure 7-3:
1. Remove the sensor cover to expose sensor components.
2. Disconnect thermocouple wires from terminals C and D on the sensor
board.
3. Remove the screw from the thermocouple mounting tab (save the
screw for installing the new thermocouple).
4. Pull the thermocouple straight up and remove it from the furnace.
5. Insert the new thermocouple into the slot in the top of the furnace.
It should go in freely; if necessary, wiggle a little to position without
forcing it in.
The thermocouple should be near, but not touching, the cell
housing or furnace heater coil .
6. Put the screw back into the thermocouple mounting clamp. This se-
cures the thermocouple to the furnace
7. Attach the thermocouple wires to terminals C and D on the sensor
board, observing polarity (yellow wire to terminal C, red wire to ter-
minal D).
8. Disconnect the furnace wires from sensor board terminals R and S.
Using an Ohm meter, check for short circuits of the heater coil to the
metal thermocouple sheath. Check that neither furnace lead is short
circuited to the metal furnace cover. The resistance should be infinite.
If you measure a short circuit, loosen the screw that secures the ther-
mocouple and relocate slightly until resistance is infinite.
Before performing a primary calibration, first connect power to the
sensor and allow it to heat up and stabilize (approximately one hour).
9. Perform a primary calibration.
NOTE
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NOTE
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