GAI-Tronics 262-001 Intrinsically-Safe Telephones - Manual (Page 6)

Pub. 42004-173G
Model 262-001 and 272-001 Intrinsically-Safe Telephones Page 6 of 12
f:\standard ioms - current release\42004 instr. manuals\42004-173g.doc
08/14
Maintenance
This section includes two troubleshooting charts designed to quickly pinpoint the source of problems.
Troubleshooting
N OTE : It may be advantageous to temporarily connect a Model 262-001 or 272-001 Telephone panel
directly to the output terminals of the Model 263-000 IBU when troubleshooting. Then, using the charts
below, the cause of the problem should more easily be determined.
Non-Equipment Related Problems
Problem Solution
The I.S. telephone is inactive
with no lights on the IBU when
the telephone is off-hook. 1. Check the ac power to the Model 263-000 IBU.
2. Check the ac fuse F4 at the Model 263-000 IBU.
3. Ensure there is no wiring open at the I.S. telephone.
The I.S. telephone has no dial
tone. 1. If the I.S. telephone has a wiring short, the IBU lights will be lit
in the following pattern:  =
On
, 
= Off
ISLOOP

LOCK

HOOK

TELCO

2. If the TELCO line has an open, the IBU lights will be lit in the
following pattern:  =
On
, 
= Off
ISLOOP

LOCK

HOOK

TELCO

The lights on the IBU flash
randomly. The I.S. telephone has an intermittent wiring short. The short may be
between the conductors or either/both conductor(s) to ground/shield.