Tritech International Ltd
Intelligent Gyro Compass
11.7
Dismantling and Re-assembly
Before starting to dismantle the iGC:
1.
Refer to Section 4.2 - Safety Notes at the beginning of this manual.
2.
All relevant parts of this section of the manual should be read and understood.
3.
Refer to the Appendices for details of exploded views and identification of components.
4.
Ensure that power to the iGC has been turned off, the connector disconnected and the iGC
removed to a suitable workshop environment. Opening the iGC
The main components inside the iGC include:
1. Sensor Assembly (Item 3), which consists of the top two boards;
2. Interface PCB Assembly (Item 4) – the blue circular PCB;
3. Processor module (Item 24) – the small PCB underneath the interface PCB.
4. Underwater connector tails and orange interface connector (Item 11).
The Sensor Assembly, Interface PCB and Processor module should be regarded as a single
replaceable unit.
11.7.1
Removal Of pressure Dome
The procedure for removal of the dome is as follows:
1.
Thoroughly clean and de-grease the outside of the iGC.
2.
Unscrew the dome (Item 1) from the end cap (Item 2). Normally this can be done
by hand with the assistance of clean rubber gloves (or rubber sheet) to improve grip on the smooth
anodised surface. If additional torque is required a pair of strap wrenches can be used, or fasteners
can be inserted into the end cap to allow it to be held in a vice and a strap wrench then used to
unscrew the dome.
In all cases care must be taken to avoid damaging the anodising.
11.7.2 Removal Of Sensor Assembly, Interface PCB and Processor Module
The procedure for removal of the Sensor Assembly, Interface PCB and Processor Module (as a single
unit) is as follows:
1. Remove the dome (Item 1).
2. Unscrew the two cross head screws (Item 16) that attach the two regulators to the
heatsink block projecting from the end cap base. Remove the washers (Item 13), small
plastic insulating bushes (Item17) and the flat insulating washer (Item18) and store
carefully.
3. Unscrew the three M3 socket head cap screws (Item 12) that attach the Interface PCB
(Item 4) to the three hexagonal spacers (Item 10).
4. Raise the stack of PCBs together and remove the cable end plug (Item 11) from the
orange connector on the Interface PCB.
Issue 2
0707-SOM-00004
Page 34 of 51