Hubbell 670-801-UL Stereo Amplifier User Manual


 
Pub. 42004-615L2
Model 670-801-EX and 670-801-UL SmartSeries Amplifiers Page: 12 of 15
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Maintenance
In order to verify and ensure explosion-proof integrity, perform regular preventive maintenance and
inspection checks on the GAI-Tronics explosion-proof stations. The GAI-Tronics Field Service
Department can formulate a service contract to suit specific preventive maintenance needs.
CAUTION
Remove power from the enclosure before performing any maintenance.
Use the following procedures to ensure reliable operation of your equipment:
1. Remove power from the enclosure.
2. Unbolt the cover. Remove the amplifier from the enclosure.
3. Visually check the interior of the enclosure for signs of contamination. Contamination inside the
enclosure could mean that the conduit seals or cable gland seals have been compromised.
4. Ensure the gasket and hardware are in place and in good condition. Reinstall the amplifier and
enclosure cover. Restore power to the unit.
In certain circumstances, it may be necessary to re-terminate some or all of the enclosures in a system.
When this is done, strip the wires back to clean copper, and make wire connections to each terminal.
If contaminants from the plant atmosphere have entered the enclosure, clean the interior. Often, a solvent
contact cleaner is not strong enough to wash away the buildup. If this occurs, try the following steps:
1. Disconnect power from the enclosure.
2. Disconnect all wires from the terminal strip inside the box.
3. Spray the interior of the enclosure with a heavy-duty, surfactant-type, water-based industrial cleaner.
Heavy concentrations of contaminants may be scrubbed with a scrub pad or a soft brush.
4. Rinse the interior of the box with a water spray, and blow out any excess water using compressed air.
5. Apply a coating of water-displacement solution followed by contact cleaner and compressed air.
6. Strip wires back to clean copper before reconnections.
7. Reinstall the amplifier and enclosure cover. Reapply the power.
Troubleshooting
The following suggestions are provided to aid a technician in troubleshooting.
Problem Solution
Feedback during page of nearby
handset station.
Use the muting feature in the amplifier enclosure at the terminal
blocks.
Crosstalk
One or more system cable pairs may be improperly terminated.
Visually inspect the system cable for accidental crossing of cable
pairs or grounds.