Ametek CEM/Humox, Руководство пользователя

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7-8 | Thermox CEM/Humox Analyzer
Furnace Replacement
To replace the furnace, do the following (see Figure 7-3):
1. Disconnect cell clips.
2. Remove the thermocouple from the furnace (see the “Thermocouple Replace-
ment” section in this chapter for help).
3. Disconnect the furnace leads from terminals R and S on the sensor board.
4. Loosen the compression fitting on the underside of the cell housing and the union
fitting on the convection loop return. To prevent stripping threads on any of
the fittings, we suggest that you loosen each in turn at small increments - don’t
completely loosen the one fitting and then try to loosen the other fitting.
5. While holding the furnace in one hand, remove the convection loop mounting
clamp, being sure to save the mounting clamp for when you install the new
furnace.
6. Gently pull the cell housing out of the furnace and remove the furnace.
7. Slip the new furnace onto the cell housing and attach the cell housing using the
convection loop mounting clamp.
8. Remount the cell housing (reverse the actions taken in step 4).
9. Reinstall the thermocouple (reverse the actions taken in step 2).
10. 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 thermocouple and relocate slightly
until resistance is infinite.
11. Reattach cell clips.
12. Reattach furnace leads (reverse the actions taken in step 3 (polarity not required).