Description
Product Overview
The GE IS215VPROH2BC (VPROH2B) is a voting processor board for the GE Speedtronic Mark VI and Mark VIe turbine protection system. It is the safety core that independently watches turbine speed and triggers an emergency trip when overspeed or fault conditions exceed the protection thresholds.
This board does not depend on the main turbine controller. It runs its own processor, its own power supply and its own software, deliberately kept separate from the governing system. Three VPRO boards operate in parallel in a triple-modular redundant (TMR) architecture, and a trip command is issued only when all three vote the same way.
The VPRO reads speed from magnetic pickup sensors, evaluates protection logic, and sends trip commands through the TREG terminal board to the three emergency trip solenoids. It also manages overspeed test sequences and reports protection status to the HMI over IONet.
The H2BC suffix marks a specific revision within the VPROH2 family. This is the board that replaces the old mechanical bolt-type overspeed bolts on modern turbine installations.
GE VPROH2B IS215VPROH2BC
Core Product Features
- Independent triple-redundant protection processor, running outside the main control system for fault isolation and safety integrity.
- Reads turbine speed from multiple passive magnetic pickup sensors per protection channel, with sensor continuity and fault diagnostics built in.
- Executes overspeed, acceleration and vibration protection logic in hardware and software, independent of the governing controller.
- 3oo3 voting across three VPRO boards ensures a single faulty board neither false-trips the turbine nor prevents a needed trip.
- Drives up to three emergency trip solenoids through TREG and TRPG terminal boards at 125 VDC.
- Built-in overspeed test mode allows on-line protection testing without physically overspeeding the turbine.
- Five D-shell serial ports and Ethernet (IONet) support configuration, diagnostics and HMI communication.
- Front-panel LEDs show processor run, fault, trip and each speed channel’s health for instant rack-level checks.
- Each VPRO board has its own power supply rail, so a single control power failure cannot take the protection system offline.
Technical Specifications
| Item | Specification |
|---|---|
| Ordering model | IS215VPROH2BC |
| Board designator | VPROH2B |
| Product type | Voting protection processor board |
| Compatible platform | GE Speedtronic Mark VI / Mark VIe |
| Protection function | Independent overspeed and emergency trip |
| Redundancy | Triple modular redundant (3oo3 voting) |
| Processor | Pentium-class embedded processor |
| Memory | 16 MB DRAM; 256 KB L2 cache |
| Speed sensor inputs | Passive magnetic pickups (MPUs), multiple per channel |
| Trip solenoid output | Via TREG terminal board, 125 VDC |
| Serial ports | 5 × D-shell, up to 19200 baud |
| Network | Ethernet, IONet for HMI and diagnostics |
| Power supply | Dedicated per-board, independent of main control |
| Status indicators | Run, fault, trip, channel health LEDs |
| Operating temperature | 0°C to +45°C (controlled cabinet) |
| Mounting | Mark VI/VIe VME or rack slot |
| Safety architecture | Separate from governing control system |
| Certifications | SIL-rated system component, CE, UL |
Distributor listings quote slightly different temperature ranges and port counts. The triple-redundant architecture, magnetic pickup inputs and 125 VDC trip solenoid output are the stable facts. Confirm the exact sensor count and port configuration against your protection system drawing.
GE VPROH2B IS215VPROH2BC
Product Details and Application Fields
Product Details
Why it sits outside the main controller. The governing CPU is busy running load control and heat balance. The VPRO does one job: watch speed and trip if it exceeds the limit. Keeping that logic on separate hardware means a software crash in the governor cannot take down protection.
3oo3 voting. Three VPRO boards each read their own speed sensors. A trip happens only when all three agree. One board with a stuck sensor does not shut the unit down. One board that fails to vote during a real overspeed does not prevent the other two from tripping.
Speed sensor arrangement. Each protection channel reads its own set of magnetic pickups installed on the turbine shaft. Sensor continuity, cable resistance and signal amplitude are monitored continuously, so a bad pickup shows up as a fault long before an overspeed event.
Overspeed test. Plants must prove the protection system works on a schedule. The VPRO supports an on-line test mode that artificially injects an overspeed signal and verifies the trip chain fires, without actually overspeeding the turbine.
Trip chain. The VPRO sends a trip command to the TREG terminal board, which applies 125 VDC to the trip solenoids. The solenoids de-energize (fail-safe), dump the trip oil, and the turbine stops. This chain is hardwired and does not depend on Ethernet or the HMI.
Revision context. H2BC is a specific revision. Earlier H1 and H2 variants share the protection architecture but differ in processor speed, memory and port layout. When replacing a board, match the revision or verify firmware compatibility through ToolboxST.
Maintenance discipline. Because this board drives trip solenoids, any bench work or test must follow the plant’s turbine trip procedure. Accidentally firing a trip solenoid while the unit is online is a significant event.
Application Fields
- Independent overspeed protection for gas and steam turbines in thermal and combined-cycle power plants
- Triple-redundant emergency trip systems on utility-scale turbine generators
- Turbine protection retrofits replacing mechanical bolt-type overspeed devices
- Nuclear and heavy-industry turbine protection where SIL-rated independent protection is required
- Compressor and pump train overspeed protection in oil & gas and refining facilities
- On-line overspeed testing and protection verification during scheduled outages
- Wind turbine and hydro turbine independent speed protection on Mark VIe platforms
Related Model Recommendations
- IS200TPROH1BBB — protection terminal board that conditions MPU speed signals for the VPRO, the upstream half of the trip chain.
- IS200TREGH1BEC — trip emergency terminal board that executes the VPRO trip command at the 125 VDC solenoids.
- IS215UCVEH2AE — main Mark VIe control engine, which runs the governing logic the VPRO deliberately stays independent of.
- IS215UCVEM09A — Mark VIeS safety controller for plants requiring integrated SIL-rated protection rather than the separate VPRO architecture.
