Operation:

The VSVO provides four channels including bi-directional servo current outputs, LVDT position feedback, LVDT excitation, and pulse rate flow inputs.The TSVO provides excitation for, and accepts inputs from, up to six LVDT valve position inputs. One, two, three, or four LVDTs can be selected for each servo control loop, and if three inputs are used, they can be used for gas turbine flow measurement applications. These signals are transmitted through the TSVO and sent directly to the front of the VSVO board at J5. Each servo output is equipped with a firmware-controlled, independent suicide relay that short-circuits the VSVO output signal to common in the event of a power failure and returns it to the nominal limit when a manual reset command is issued. Diagnostics monitor the output status of each servo voltage, current, and suicide relay.

Description:

General Electric’s IS200TSVOH1BAA circuit board assembly is part of the company’s Mark VI turbine control system. The Mark VI has been monitoring and controlling industrial turbine systems for decades. Meanwhile, Speedtronic systems have been in use since the late 1960s.

This IS200TSVOH1BAA is used as a servo valve termination board. While MKVI systems use many different termination boards, this particular board is a barrier type board that uses screws to clamp the wire connections. When connecting wires to the terminals, it is important to strip the wires to the correct length; otherwise, the screw clamps will be difficult to access.

This IS200TSVOH1BAA has two termination blocks located on one side of the board. Other connectors used on the board include d-shell connectors and vertical plugs. The board has six jumper switches that can be used to change the way a particular circuit works. Each jumper switch on the board has multiple settings. Before removing a jumper from the unit, be sure to make note of the way the jumpers were set on the previous board; best practice suggests duplicating these settings on the new assembly.

Other board components include relays, transformers, ICs, and transistors. For more information on these components and how the board should be located, wired, installed, and maintained, refer to the GE Speedtronic manual.