Maintenance; General; Handset With Cord Replacement (Instructions For Trained Technician) - Lucent Technologies 520B Manuel D'utilisation

5. Align the apparatus unit with the base to permit the depression of the locking pin into the hole in the
base. Depress the locking pin and tighten the No. 8-32 Allen Setscrew. The cover may now be
secured to the apparatus unit by means of the three mounting screws.
6. Reconnect the telephone line wire at the protector.

Maintenance

GENERAL

Any set requiring repair or replacement should be removed from service by a Lucent Technologies
Technician or person trained in the installation and repair of telephones in an explosive environment and
returned to the Lucent Technologies Service Center. Repair of Explosive Atmosphere Wall Telephones
must be accomplished in accordance with Manufacture's guidelines, the National Electrical Code, and
local building code. The only components which may be replaced on site are the dial, the Switchhook
Assembly, and the Handset with Cord. All other failures must be returned to the Lucent Technologies
Service Center for repair/replacement.
WARNING: Before removing the Explosive Atmosphere Wall Telephone set for any
reason, be sure the line wires are disconnected and secured at the protector. Defects
due to any cause, even though seemingly slight, must be corrected without delay.
To remove the Explosive Atmosphere Wall Telephone set from service after disconnecting line wires at
the protector, remove the three mounting screws securing the cover and loosen the No. 8-32 Allen
Setscrew until the locking pin pops out. The apparatus unit may now be screwed off the base. Care
should be taken to avoid contamination of threads with dirt or grit.

HANDSET WITH CORD REPLACEMENT (INSTRUCTIONS FOR TRAINED TECHNICIAN)

To replace the Handset with Cord, remove the Explosive Atmosphere Wall Telephone set from service by
disconnecting line wires at the protector. Remove the three mounting screws securing the cover and
loosen the No. 8-32 Allen Setscrew until the locking pin pops out. The apparatus unit may now be
screwed off the base. Care should be taken to avoid contamination of threads with dirt or grit. Move the
apparatus unit to an area where the danger from explosive atmospheres does not exist. Loosen the front
cord strain relief screw. Carefully turn the apparatus unit to allow access to the interior of the telephone.
Loosen the dial assembly (either Rotary or Touch-Tone) to allow access to the handset cord bushing.
Remove the cord clamp located near the handset cord bushing. Loosen the terminal screws securing
each handset wire to the network, taking care to note the terminal location of each wire color, and remove
the wire leads from the network. Carefully loosen the knurled bushing nut by inserting a large screwdriver
in the slot and then tapping the screwdriver handle with a hammer so as to drive the nut in a counter-
clockwise direction. Gently tap the center of the bushing using a rubber mallet and a piece of wood to
remove the bushing and the handset cord assembly from the telephone housing. Carefully pull the wires
through the housing and remove the handset cord and bushing assembly.
WARNING: Extreme care must be taken to ensure that no component of the set is
damaged. Damage of any type to any component of the set while replacing either a
Handset with Cord, Switchhook Assembly, or dial, will require the Explosive Atmosphere
Wall Telephone set to be returned to the Lucent Technologies Service Center for repair
or replacement.
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