IS200TTURH1CFD Open Box: Function and Wiring Layout

This IS200TTURH1CFD is an open-box unit — factory packaged and unused, with the outer packaging opened or damaged in handling, cleaned and tested before listing. It's a Turbine Control Terminal Board (TTUR) from GE's Mark VI Speedtronic system, and its main job is providing the physical wiring interface for turbine speed and generator synchronizing signals. Field connections — magnetic speed pickups, shaft voltage/current sensors, potential transformer leads, and breaker relay wiring — land on two removable terminal blocks, TB1 and TB2, each with 24 screw terminals accepting wire up to #12 AWG, with a shield termination strip beside each block tied to chassis ground. A third block, TB3, is available for optional TTL active speed pickups that need their own external power source. Jumpers JP1 and JP2 configure the board for simplex or TMR relay-drive operation.

The TTUR itself doesn't run the control logic — that happens on a separate VME card, VTUR, mounted in the R/S/T Control Module, which the TTUR reaches by cable through six connectors: JR1/JR5, JS1/JS5, and JT1/JT5. Once turbine speed matches line frequency and generator/bus voltages line up, the board energizes the generator breaker coil (52G) at a nominal 125 V DC through the K25/K25P/K25A permissive relay chain, closing the breaker for synchronization.

Confirm the Fault Before You Install a Replacement

Even with a spare in hand, it's worth ruling out the more common causes of turbine speed and synchronizing alarms before installing this board:

• Check the terminals on TB1/TB2 for looseness or corrosion, and confirm the JR/JS/JT cable connectors are fully seated — these are more common failure points than the board itself.
• For synchronizing failures, check the PT wiring and fuses, the external synch check relay, the 52G/a breaker feedback contact, and the JP1/JP2 jumper settings.
• For speed or overspeed alarms, check the magnetic pickup's air gap and cabling before assuming a board fault; in TMR systems this usually shows up as a channel voting disagreement rather than an outright failure.
• For shaft voltage/current alarms, suspect a grounding brush or bearing insulation issue on the shaft train — the board only monitors that condition, it doesn't cause it.

Reading the IS200TTURH1CFD Part Number

IS200 is the platform prefix, TTUR the function code, and H1CFD the group and revision — H1C for the group/generation, FD for this specific revision. Order and quote against the complete string, since H1C is a different hardware generation from the H1B-series TTUR boards also stocked in this collection. Our GE Speedtronic Part Number Decoder explains how to parse a full IS200 string.

Related Boards

The TTUR pairs with the VTUR VME card inside the Control Module. The generator breaker trip circuit also involves the TRPG terminal board (driven by VTUR) and, in the Backup Protection Module, the TREG terminal board (driven by VPRO). If you also support Mark V equipment, see our Mark V vs Mark VI: DS200 to IS200 guide and GE Mark V DS200 Boards Explained article. Browse the rest of the family in our GE Mark VI IS200 Boards collection or the wider GE Speedtronic Turbine Control Boards collection.

What to Include in Your Quote Request

• Full part number with suffix: IS200TTURH1CFD
• Revision from the label
• Photo of the ID label
• Turbine/generator model and unit ID
• Planned outage or urgent need
• Quantity

Request a Quote

This IS200TTURH1CFD is listed as new surplus, open box, cleaned and tested, with a 1-year warranty (see table below). We quote every order directly rather than posting prices online — submit a Request a Quote and expect a response within 24 hours. We ship worldwide DDP, accept purchase orders, and support both planned outages and urgent breakdown needs.

General Information about the Product
Part Number	IS200TTURH1C Mark VI IS200
Description	GE General Electric IS200TTURH1C IS200TTURH1CFD Turbine Control Terminal Board Mark VI OPEN BOX
Condition	newSurplusNoBox Cleaned and Tested. With 1 Year Warranty.