IS200VTURH2BAC: The VME Turbine Protection Card, Explained

Offered in used, cleaned-and-tested condition, the IS200VTURH2BAC is the H2B-revision VME turbine protection (VTUR) card from GE's Speedtronic Mark VI line. It is one of the rack's most safety-critical boards: it derives turbine speed from magnetic pickups, generates the primary overspeed trip, monitors induced shaft voltage and current, and supervises the flame detectors on gas turbines. It seats on the VME control bus and works with the TTUR terminal board for field wiring and the TRPx trip boards for the trip solenoids.

Primary overspeed protection and speed sensing

The VTUR's central duty is protecting against overspeed. It accepts up to four passive magnetic pickups across roughly 2 Hz to 20,000 Hz, takes the median speed for control and for the primary overspeed trip, and can resolve very low rotation to support zero-speed and turning-gear detection. On a trip it energizes three primary overspeed relays on the applicable TRPx board (TRPG for gas, TRPS or TRPL for steam) to command the emergency trip devices. It additionally monitors induced shaft voltage and current, alarming on excessive levels. In TMR systems a VTUR is fitted in each of the <R>, <S>, and <T> cores and the results are voted; simplex systems use one card. Independent emergency overspeed protection is provided by the VPRO card in the <P> protection core.

Rule out the wiring and terminal boards before ordering

A used protection card is worth fitting only after the fault is pinned to the card itself. These common complaints usually point elsewhere:

• Speed reading missing or erratic: check the magnetic pickup and gap, the wiring back to TTUR, and the JR5 speed cable. In TMR a single bad channel is voted out, so it seldom means the card is bad.
• Overspeed trip that should not have occurred, or a trip test that will not finish: the TRPx and TREx boards, the trip-solenoid (ETD) wiring, and the trip power feed are the usual culprits.
• Flame-loss alarms on gas turbines: a sooted Geiger-Mueller detector or a fault in its external supply through TRPG mimics a card fault.
• Automatic synchronizing or 52G breaker trouble: the PT inputs and breaker relays live on TTUR, so the fault is typically there.
• Controller cannot see the card: reseat it and verify backplane power and firmware revision before condemning it.

Confirming which element latched in the HMI diagnostics is the reliable way to avoid swapping a serviceable board.

Decoding IS200VTURH2BAC

The identifier breaks down as IS200 (Mark VI IS200 board series), VTUR (VME turbine primary-protection function), H2 (hardware group), B (functional revision), and AC (artwork and coating revision). H1A, H1B, and H2B are revisions of the same VTUR function, and because some systems are configured for a specific revision, you should match the full string on your existing card rather than mixing groups. For a field-by-field explanation, use our GE Speedtronic Part Number Decoder.

Related boards and cross-generation notes

Plan the VTUR with its partner hardware: the TTUR terminal board that lands the pickups, shaft, PT and breaker wiring (via JR5 and JR1), the TRPx/TREx trip boards, and the independent VPRO emergency protection card. Browse the GE Mark VI IS200 Boards collection and the broader GE Speedtronic Turbine Control Boards range for these parts. The card is documented in GE's Mark VI System Guide, GEH-6421. If your fleet includes earlier Speedtronic controls, our Mark V vs Mark VI: DS200 to IS200 guide explains how turbine protection was carried forward from the DS200 generation to IS200.

What to attach to your quote request

• The full part number and suffix on the label (IS200VTURH2BAC) and any further revision codes
• A photo of the board label
• Turbine model and Mark VI generation
• Simplex or TMR configuration, and the affected core if known
• Quantity and urgency

Request your VTUR quote

This IS200VTURH2BAC 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. As this is a protection card, share your turbine model and urgency so we can confirm the correct revision and lead time.