The IS200VPROH2B is a PCB component from GE for the Mark VI system. The MKVI is a gas and steam turbine management system released by GE as part of the Speedtronic line, which has been developed by General Electric over four decades, starting with the MKI.
The IS200VPROH2B functions as an Emergency Turbine Protection Board. Along with the TPRO and TREG boards, the IS200VPROH2B are the independent overspeed protection system for the Mark VI system. This includes three VPRO boards (triple redundant) that control the trip solenoids through the TREG board in a module that is separate from the turbine control system. The IS200VPROH2B has nine thermocouple inputs for exhaust over-temperature protection, as well as three analog current inputs, and backup synchronization check protection.
The IS200VPROH2B has two backplane connectors. The board also has two long, narrow female plugs located near and parallel to the front faceplate. There is a vertical pin (male) ribbon connector located on the rear edge. The front faceplate also includes many connectors, such as a single DIN connector and several multi-pin D-shell cable connectors. There is also a single female power plug located in the front panel, as well as several LED indicators. The board has an onboard power supply. This power supply generates 5 V dc and 28 V dc supplied from the cabinet PDM. Connectors and indicators located on the front panel are labeled.
It is worth noting the IS200VPROH2B is a lower power version of an IS200VPROH1 board. The IS200VPROH2B can only support a single TREG board; if two of these boards are necessary it is necessary to use the higher powered version of this board.