The IS200VCMIH1B is a VCMI Communication Board for the Mark VI system. It utilizes SIFT Voting (Software Inplemented Fault Tolerance) as a feature built into the board. Along with other VCMI boards located in the Mark VI control rack, the IS200VCMIH1B allows for communication with I/O boards.
The IS200VCMIH1B is built with a front faceplate. The faceplate has many components mounted into its surface. Starting at the top of the faceplate, these include: a single line of three LED lights followed by a reset switch, a 9-pin serial port connector, two rows of four LED indicators that are all labeled “module,” followed by two rows of three LED indicators labeled R, S, and T. Finally, the board has another single line of three LED lights that is followed by a DIN connector. Each of these components is wired to the surface of the IS200VCMIH1B board.
The IS200VCMIH1B is built with two backplane connectors. These are placed side-by-side on the rear edge. The board has two other pin connectors that are both located behind the front faceplate. This includes a vertical pin connector and a male vertical pin ribbon connector. The board also has several connectors made from conductive traces on the board.
The IS200VCMIH1B is mounted in the Central Control Module and is used for internal communications between I/O cards in various locations. When this card is replaced, it is important to note the rack needs to be powered down and the IONet connector must be unplugged from the board front before beginning the process. This leaves the network still running through the T-fitting. Full replacement instructions for this board can be found in GE publication GEH6421 Vol I.