GE sized the Mark VI servo termination hardware at two valves per board. The IS200TSVOH1B accepts the coil and position-feedback wiring for a pair of electro-hydraulic servo valves — typically the servos stroking fuel or steam valves — and routes both loops to the control electronics. Offered here is the IS200TSVOH1BAA revision of that board in used condition, cleaned and tested before it ships, with warranty terms stated in the table below.

Two Servo Valves, One Termination Board

Each of the board's two valve interfaces carries the servo coil drive going out and the LVDT position feedback coming back, so the control system always knows where the valve actually is. Field devices wire directly to two I/O terminal blocks mounted on the board; per GE-derived documentation, each block provides 24 terminals accepting wiring up to #12 AWG and is secured by two screws, with a shield termination strip tied to chassis ground immediately to the left of each block. Landing those shields correctly is not optional housekeeping — LVDT feedback is a low-level AC signal, and poor shield practice shows up later as position noise that gets blamed on electronics.

Servo Alarms: Reading the Evidence Before You Buy

The documentation for this board family lists three monitored fault classes: servo current out of limits or a non-responsive servo, regulator feedback out of limits, and a failed ID chip. Only the last one starts at the terminal board. For the rest:

• Check the servo valve itself before any electronics — coil resistance measured at the terminal block, and hydraulic cleanliness, since a silted valve answers commands slowly and trips current limits.
• Ring out the LVDT circuits: excitation present, secondary signals plausible, no swapped or open pairs. Feedback faults overwhelmingly originate in the transducer or its cabling.
• Inspect and reseat the cables toward the servo processor; a half-seated connector produces channel-specific ghosts.
• Only when the fault stays with the board position after those checks — or the system reports an ID/hardware fault on the board itself — should the TSVO go on the purchase order.

Suffix and Revision: What H1B and AA Tell You

IS200TSVOH1BAA breaks down as IS200 (Speedtronic board series), TSVO (Servo Terminal Board), H1B (hardware group and version), and AA (production revision). The H1A group also exists in the field; because GE's public literature does not document the functional difference, the safe practice is to replace an H1B with an H1B and let the revision letters tell us which build era your cabinet holds. Full details on GE's scheme live in our GE Speedtronic Part Number Decoder.

Trip Integration and Redundancy Connections

Two cables link the TSVO to the VSVO servo processor — one at the J5 plug on the VSVO front, one at the J3/J4 connectors on the VME rack. Simplex installations use the JR1 connector, while TMR installations distribute signals across JR1, JS1, and JT1 for the <R>, <S>, and <T> channels. Plugs JD1 and JD2 take an external trip from the protection module, so a protective action can reach the valve interface independently of the normal control path. On Mark VIe upgrades the same terminal board concept is serviced by the IS220PSVO I/O pack instead of a VME card. Related boards live in GE Mark VI IS200 Boards and the wider GE Speedtronic Turbine Control Boards range; the guide Mark V vs Mark VI: DS200 to IS200 covers the platform history.

What Your RFQ Should Include

• The complete label string — IS200TSVOH1BAA for a like-for-like match
• A photo of the board label if the unit is accessible
• Turbine model and control platform, plus VSVO or PSVO on the loop
• Simplex or TMR arrangement and how many boards the position uses
• Quantity and delivery urgency

Ordering the IS200TSVOH1BAA

Send your Request a Quote and our team will respond within 24 hours. Purchase orders are welcome, and every shipment goes out DDP to destinations worldwide, so the landed cost and customs handling are settled before dispatch. Condition and warranty for this specific board are documented in the table below.

General Information about the Product
Part Number	IS200TSVOH1B Mark VI IS200
Description	GE General Electric IS200TSVOH1B IS200TSVOH1BAA Termination Servo Board Mark VI
Condition	used Clean and Tested. With 1 Year Warranty.