IS200VTURH1BAA: The Mark VI VME Primary Turbine Protection Card

The IS200VTURH1BAA is GE's VME Primary Turbine Protection card for the Speedtronic Mark VI, one of the most safety-critical boards in the control rack. Known in the field as the VTUR or "VME turbine" card, it measures turbine speed, generates the primary overspeed trip, monitors induced shaft voltage and current, and, on gas turbines, watches the flame detectors. It plugs into the VME bus of the control section and works hand in hand with the TTUR terminal board that carries the field wiring.

Speed sensing and the primary overspeed trip

VTUR reads up to four passive magnetic speed pickups over a frequency range of roughly 2 Hz to 20,000 Hz, sensing a toothed wheel on the shaft. The median of the speed signals is used both for speed control and to generate the primary overspeed trip, and the circuit is sensitive enough to resolve very low rotation, which supports zero-speed and turning-gear detection. When an overspeed trip is required, VTUR drives the three primary overspeed trip relays on a TRPx trip terminal board (TRPG for gas turbines, TRPS or TRPL for steam), which in turn act on the emergency trip devices. In a triple-redundant (TMR) system a VTUR sits in each control core, <R>, <S>, and <T>, and the results are voted; a simplex system uses a single card.

Diagnose before you buy: speed, trip, and flame faults that mimic a bad VTUR

The VTUR is expensive and safety-critical, so it is often replaced prematurely. Most of what looks like a VTUR failure actually lives in the sensors, the terminal boards, or the wiring. Check these first:

• No speed or erratic RPM. Suspect the magnetic pickup and its gap, the pickup-to-TTUR field wiring, and the speed cable (JR5) before the card. In a TMR system, if only one core reads bad speed, the problem is almost always that core's pickup, wiring, or cable, or that single VTUR, and the other two cores vote it out.
• Unexpected overspeed trip, or failure to trip on test. The trip path runs through the TRPx and TREx trip boards, the trip-solenoid (ETD) wiring, and the trip power feed. Confirm which element latched from the HMI diagnostics before you condemn the VTUR.
• Loss-of-flame nuisance trips on gas units. The eight Geiger-Mueller flame detectors interface through the TRPG board and require an external supply. Carbon or soot on a detector, or a fault in its high-voltage feed, imitates a card fault, so inspect the detector and its wiring first.
• Synchronizing or breaker (52G) issues. Generator and bus potential-transformer signals and the breaker permissive relays live on the TTUR terminal board. A sync or breaker complaint is usually TTUR or the PT wiring rather than the VTUR.
• Card not seen by the controller. Check the VME seating, the backplane and rack power, and firmware or revision compatibility before assuming the board is dead.

Independent, emergency overspeed protection is handled separately by the VPRO board in the <P> protection core, so confirm whether a trip originated in the primary (VTUR) path or the emergency (VPRO) path before ordering.

How the IS200VTURH1B part number and suffix work

IS200 identifies the Mark VI IS200 board series, VTUR is the functional acronym for the VME turbine primary-protection card, H1 is the hardware group, B is the functional revision, and the trailing AA is the artwork and coating revision. The H1A, H1B, and H2B builds are revisions of the same VTUR function; some systems are revision-sensitive, so match the full string on your card's label rather than assuming interchangeability. Our GE Speedtronic Part Number Decoder explains each field.

Companion boards: TTUR, TRPx, and VPRO

VTUR never works alone. The TTUR terminal board lands the speed pickups, shaft pickups, generator and bus PTs, and breaker relays, and connects to VTUR through the JR5 and JR1 cables. The TRPx/TREx trip boards carry the overspeed trip relays and drive the emergency trip devices, and the VPRO board provides independent emergency overspeed protection. You can browse related cards in the GE Mark VI IS200 Boards collection and the wider GE Speedtronic Turbine Control Boards catalog. Detailed operation is documented in GE's Mark VI System Guide, GEH-6421. If you are moving up from an earlier platform, our Mark V vs Mark VI: DS200 to IS200 guide covers how turbine protection changed.

What to send with your quote request

• The full part number and suffix from the label (IS200VTURH1BAA) and any revision markings
• A clear photo of the board label
• The turbine model and Mark VI generation
• Whether the system is simplex or TMR, and which core is affected
• Quantity and urgency (planned spare or active outage)

Request a quote for this VTUR

This IS200VTURH1BAA is offered used, cleaned and tested, backed by the warranty shown below. Click Request a Quote and our team responds within 24 hours. We ship worldwide DDP and accept purchase orders from qualified organizations. Because the VTUR is safety-critical, tell us your turbine model and urgency and we will confirm the correct revision and lead time.