COBHAM SEA TEL 9711IMA-70, Installation Manual

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Installation Troubleshooting 9711IMA-70
14-2
heading) go to step 2. If it moves in the correct direction but does not display the correct heading go to
step 3. The gyro compass connects to the R1, R2, S1, S2 and S3 terminals.
CAUTION - Electrical Shock Potentials exist on the Gyro
Compass output lines. Assure that the Gyro Compass output is
turned OFF when handling and connecting wiring to the
Terminal Mounting Strip.
1.
The Ships Heading display does not change when the ship changes direction. Using
a multimeter read between R1 and R2. It should read 115 VAC. If it does not then a fuse is
blown at the gyro repeater or there is an open between the repeater and the ACU. Read
between S1 and S2, S2 and S3 and finally S3 and S1. They should all read between 0 and 90
VAC. The voltage level will change as the ship turns. If one reading is very close to 0 volts wait
until the ship has made a major change in heading and then check voltage again. If the reading
is still very low there is a problem in the line between the gyro repeater and the ACU or a
problem in the gyro repeater itself.
2.
The display changes in the direction opposite of the movement of the ship. Switch
the secondary leads S1 and S2. Caution: there is 90 VAC between them! Verify that when the
ship changes direction the display shows change in the same direction. If the direction is
correct but the heading is incorrect go to step C.
3.
The ship's heading display does not indicate the correct heading. If the display is off
by 60, 180 or 300 degrees, this indicates that R1 and R2 are reversed. Reverse R1 and R2 and
recheck the heading display. If the display is off by 120 or 240 degrees, this indicates that S1,
S2 and S3 are in the right order but off by one place. Note their positions and carefully move
the connections one position over (S1 to S2, S2 to S3, and S3 to S1). This action will offset the
display by 120 degrees. Check if the display now reads correctly. If not move all three leads
one more time in the same direction as last time. Verify that the ship's heading is correct.
14.1.3. 360:1 Synchro
Observe the ship's heading display on the ACU. Compare its movement with that of the ship. If it does
not move at all go to step 1. If it moves but in the wrong direction (even if it does not display the correct
heading) go to step 2. If it moves in the correct direction but does not display the correct heading go to
step 3. The gyro compass connects to the Terminal Mounting Strip on TB3- R1, R2, S1, S2 and S3.
CAUTION - Electrical Shock Potentials exist on the Gyro
Compass output lines. Assure that the Gyro Compass output is
turned OFF when handling and connecting wiring to the
Terminal Mounting Strip.
1. The Ships Heading display does not change when the ship changes direction. Using a
multimeter read between R1 and R2. It should read 115 VAC. If it does not then a fuse is blown
at the gyro repeater or there is an open between the repeater and the ACU. Read between S1
and S2, S2 and S3 and finally S3 and S1. They should all read between 0 and 90 VAC. The
voltage level will change as the ship turns. If one reading is very close to 0 volts wait until the
ship has made a major change in heading and then check voltage again. If the reading is still
very low there is a problem in the line between the gyro repeater and the ACU or a problem in
the gyro repeater itself.
2. The display changes in the direction opposite of the movement of the ship. Switch the
secondary leads S1 and S2. Caution: there is 90 VAC between them! Verify that when the ship
changes direction the display shows change in the same direction. If the direction is correct but
the heading is incorrect go to step C.
3. If the ship's heading is different than the bridge, select the HDG function in the SHIP display
mode by pressing the SHIP key 4 times. Key in the correct heading using the numeric keys and
press ENTER.
EAR Controlled - ECCN EAR99