What the IS215VPROH2B Emergency Protection Board Does

The IS215VPROH2B is the Emergency Turbine Protection board — VPRO — for the GE Speedtronic Mark VI control system. It sits outside the turbine control loop entirely: it is a separate, independent protection module whose only job is to watch for an overspeed condition and drive the trip solenoids if one occurs. Three VPRO boards run in parallel inside the protection core (commonly labeled <P>, with individual channels referred to as <X>, <Y> and <Z>), so a single board problem does not take the protection function down with it.

This is the H2 design — a lower-power version of the VPRO family that supports one TREG terminal board. The H1 version supports a second TREG, driven from VPRO connector J4, for applications that need the extra channel. The H2BD you are looking at is a specific functional revision of that H2 design; see below for what that means for compatibility.

Where It Sits in the Mark VI Protection Core

Each VPRO channel is powered independently from the PD (power distribution) core through its own dedicated supply switch and fuse, not shared with the other two channels. On the communications side, VPRO does not sit on the VME backplane with the rest of the I/O; it reaches the controller over IONet, the coax network that also links the VCMI boards in the <R>/<S>/<T> control racks. The VCMI is what translates that IONet traffic back to the UCVE processor — VPRO and UCVE never talk directly.

Downstream, the VPRO controls trip solenoids through the TREG terminal board: TREG supplies the positive connection to the solenoids, and its companion TPRO board supplies the negative side. The turbine can be tripped from either terminal board, part of how GE built redundancy into the hardwired trip path, separate from the software logic.

Diagnose Before You Buy

A VPRO-related alarm on the HMI does not automatically mean the VPRO card itself is bad. Field reports on this board family point to a few recurring look-alikes worth ruling out first:

• Dead board vs. dead power feed. A VPRO with no LED activity at all can mean a blown fuse or open switch on its dedicated PD supply, not a failed card. Confirm the PD-core switch and fuse for that specific channel before condemning the board.
• One bad channel can alarm all three cores. Because VPRO and VCMI share the same IONet, a single VPRO channel going down has been known to trigger VCMI diagnostic alarms across <R>, <S> and <T> at the same time. Three simultaneous alarms do not necessarily mean three bad boards — check whether they all trace back to one channel first.
• Known chip/socket issue on older boards. GE's TIL-1905 documents an intermittent IONet communication problem on VPRO and VCMI boards manufactured between May 2006 and February 2009, caused by oxidation in a socketed transceiver chip rather than an outright board defect. Worth asking your repair shop to check for it if your board falls in that build window.
• Environment can mimic a card fault. RF interference from handheld radios used near an open panel, poor grounding, corrosion, and condensation inside the cabinet have all been documented causes of intermittent, VPRO-like diagnostic alarms.

Because this module exists purely for emergency overspeed protection, we won't guess at trip setpoints, voting logic, or test procedures here. For anything involving an actual trip test, go to GEH-6421 and your plant's approved test procedure.

Reading the IS215VPROH2BD Part Number

IS215 identifies the board as a Mark VI-generation assembly; VPRO is the function; H2 is the design group confirmed above (single-TREG, lower power); the trailing letter — here, D — is a specific revision level. Treat that revision letter as something to match exactly against your existing board and Toolbox configuration rather than assume it's interchangeable. If you're unsure whether your system will accept a different revision, send us a photo of the label and we'll confirm before you order.

Related Boards and Documentation

If you're sourcing a VPRO, there's a good chance you're also managing VCMI, terminal boards, or older Mark V hardware in the same outage. Our GE Speedtronic Part Number Decoder covers how to read any IS200/IS215-prefixed board, and if you're working across control generations, Mark V vs Mark VI: DS200 to IS200 explains how the two families map to each other. Browse the rest of the rack in our GE Mark VI IS200 Boards collection.

What to Include in Your Quote Request

• Full part number including suffix (IS215VPROH2BD) and revision
• A photo of the board label, if you have access to the failed unit
• Turbine model and Mark VI configuration (simplex or TMR)
• Quantity needed and how urgent the outage is

Request a Quote

This IS215VPROH2BD is available as new surplus, factory packaged, with a 1-year warranty. We quote worldwide with DDP shipping, accept POs, and turn quotes around within 24 hours. Click Request a Quote to get started — we never publish pricing online because every quote is matched to your exact configuration and urgency.

General Information about the Product
Part Number	IS215VPROH2B Mark VI IS215
Description	GE General Electric IS215VPROH2B IS215VPROH2BD Turbine Protection Mark VI NEW
Condition	newSurplusFactoryPackage Original Factory Packaged. With 1 Year Warranty.