COBHAM Sea Tel 9711-56 IMA C Band, Installation Manual

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Sea Tel 9711-56 IMA Installation Troubleshooting
16-3
EAR Controlled - ECCN EAR99
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.