IS200TTURH1CAA: Six Connectors, One Terminal Board
A distinctive feature of the IS200TTURH1CAA — GE's Turbine Control Terminal Board for the Mark VI Speedtronic system — is its set of six labeled D-type cable connectors: JR1 and JR5 for the R channel, JS1 and JS5 for the S channel, and JT1 and JT5 for the T channel. These carry the fanned-out TMR signals (or, in simplex mode, just the JR pair) between the TTUR and its companion VME card, VTUR, which is mounted in the Control Module and actually runs the control logic. The TTUR itself is where turbine-side field wiring lands: magnetic speed pickups, potential transformer voltage signals for synchronizing, and shaft voltage/current sensors all terminate here, on two 24-position screw terminal blocks (TB1, TB2) rated for wire up to #12 AWG.
Once turbine speed matches line frequency and generator/bus voltages are aligned, the board energizes the generator breaker coil (52G) at a nominal 125 V DC through a chain of permissive relays — K25, K25P, and K25A — backed by an external synch check relay and breaker-side feedback through a 52G/a auxiliary contact. Jumpers JP1 and JP2 configure the board for simplex or TMR relay-drive operation, and documented electrical characteristics for this board family include an MPU pulse rate range of 2 Hz to 20 kHz, an operating temperature range of -30 to 65°C, and a board footprint of roughly 33.0 x 17.8 cm — details worth checking against your specific unit's documentation (GE reference manual GEH-6421) rather than assuming they apply unchanged across every revision.
What to Rule Out Before Ordering a Replacement
- For synchronizing failures, check PT wiring and fuses, the external synch check relay, the 52G/a feedback contact, and the JP1/JP2 jumper settings before assuming a board fault.
- For speed or overspeed alarms, check the magnetic pickup's air gap and cable run to TB1/TB2; in TMR systems, one bad channel usually shows up as a voting disagreement rather than a clean failure across all three racks.
- For shaft voltage/current alarms, suspect a grounding brush or bearing insulation problem on the shaft train itself — the board only monitors that condition.
- Check that all six JR/JS/JT connectors are properly seated, and that TB1/TB2 terminals are tight, before concluding the board has failed.
Reading the IS200TTURH1CAA Part Number
IS200 is the platform prefix, TTUR the function code, and H1CAA the group and revision — H1C for the group/generation, AA for this specific revision. Order against the complete string; H1C and the H1B-series TTUR boards in this collection are distinct hardware generations. Our GE Speedtronic Part Number Decoder explains how to read a full IS200 string.
Related Boards
The TTUR's VME companion is VTUR, in 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 maintain 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: IS200TTURH1CAA
- 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 IS200TTURH1CAA is listed in used condition, cleaned and tested, with a 1-year warranty (see table below). We quote every order directly rather than publishing prices — submit a Request a Quote and expect a reply 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 |
IS200TTURH1C By General Electric IS200TTURH1CAA Turbine Control Terminal Board |
Condition |
used Cleaned and Tested. With 1 Year Warranty. |
