Filament Checkout; Connecting The Filaments - ABB PGC2000 Operation And Service Manual

Filament Checkout

1. Obtain a multimeter and select the ohms function and a range capable of measuring 40 ohms.
2. Connect one multimeter lead to each wire of the measurement filament (installed in the detector
cavity labeled "M"). The resistance measurement should be approximately 40 ohms.
3. Connect one multimeter lead to each wire of the reference filament (installed in the detector
cavity labeled "R"). The resistance measurement should be within one ohm of the measurement
filament resistance.
4. If the resistance measurements are not within one ohm of each other, ensure the multimeter is
connected and functioning correctly, and that the correct meter function is selected.
5. If the detector filaments are not in tolerance, the detector filaments are defective. The filaments
must be replaced and the checkout repeated.
6. Neither filament should contact the detector cell body. Connect the multimeter leads to one of the
filament wires and the detector cell body. The meter reading should range from several hundred
megohms to infinity.
7. Repeat this measurement for each of the other three filament wires. If all resistance
measurements are correct, go to "Connecting the Filaments." If any resistance is too low, go to
step 8.
8. If the resistance measurement is approximately 20 ohms, filament being tested is contacting the
internal wall of the detector cell cavity. When this occurs, carefully loosen the gland of the
suspect filament. Continue to loosen by hand and withdraw first the gland, then the filament from
the detector cell body (taking care not to touch or damage the filament).
9. Inspect the filament for damage or bending. If it is damaged, the filament pair will have to be
replaced.
10. If the filament is slightly bent, use small needle nose pliers to gently and carefully bend it straight.
11. If the filament orientation now appears to be correct, reinstall the detector filament and repeat the
complete checkout. If it fails again, replace the detector filament pair and repeat the harness
checkout.
12. If the filament is damaged during this attempted correction process, the filament pair will have to
be replaced.

Connecting the Filaments

1. Roll the ends of each stripped harness wire between your thumb and index finger to tightly spiral
wrap the wire ends.
2. Using a 40 watt soldering iron and approved high temperature solder, "tin" each of the harness
wire ends.
3. Roll the ends of each stripped filament wire between your thumb and index finger to tightly spiral
wrap the wire ends.
4. Using a 40 watt soldering iron and approved high temperature solder, "tin" each of the filament
wire ends.
2000-OSM, F1 8-25