NORTHROP GRUMMAN Sperry Marine NAVIGAT X MK 2, Руководство по сборке

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056341 Rev. AA NAVIGAT X Mk 2
Page 4-8 4: Preventive Maintenance
3) In the Service Setup 2 (code 610), select the gyrosphere data sub-menu to
observe the gyrosphere current:
If 45 minutes after power-up, a gyrosphere current above 300 mA is dis-
played in the gyrosphere data sub-menu, the value should be confirmed
by measuring directly at the test resistor R 54 (1
Ω
) on the main PCB.
The AC-voltage present accross test resistor R 54 in mV equals the gyro-
sphere current in mA.
4) Put the door in front of the housing and connect the grounding strap.
5) Fit the door on the housing and fasten the retaining screws.
6) If the nav. data printer NAVIPRINT is used, enter the current date and time
in the User Setup.
7) After a settling time of at least 4 hours, verify that the compass has settled
to the correct heading. The compass is to display the vessel's true heading
to an accuracy of ±0.5°.
Directly after power-up, the gyrosphere current
should not exceed 550 mA. The current will
gradually fall while the gyrosphere settles.
Within 45 minutes after power-up, the gyro-
sphere current must have dropped to a value
below 300 mA.
TEMPERATURE 42 °C
GYRO CURR 432 mA
PH BRIDGE 10 mV
GYROSHPERE DATA
TEMPERATURE 42 °C
GYRO CURR 234 mA
PH BRIDGE 10 mV
GYROSHPERE DATA
Caution
If 45 minutes after power-up, the gyrosphere current has not dropped below
300 mA, the gyrosphere is not working properly.
If visual inspection reveals no obvious cause of malfunction, the gyrosphere is
to be regarded defective and must be replaced.