Simplex or TMR: How the IS200TBCIH2B Fits Redundancy

One strength of the GE Mark VI platform is that the same contact input terminal board serves both simplex and triple-redundant control without a different part on the wall. The IS200TBCIH2B carries three connectors for exactly that reason. Wire a point simplex and it is read through connector JR1 only. Configure it for TMR and all three connectors — JR1, JS1 and JT1 — are populated, so the <R>, <S> and <T> control channels each receive their own independent copy of every field contact’s state. The field wiring itself does not change; the redundancy is built into how the board is cabled to the processing hardware.

What Lands on the Board and How It Is Read

The IS200TBCIH2B (TBCI, terminal board for contact inputs) accepts up to 24 dry contacts across two barrier-type terminal blocks, each terminal sized for wire up to #12 AWG and each block removable on two screws for service. DC excitation from the board wets the contacts, and integral noise-suppression circuitry rejects surge and high-frequency interference. The conditioned signals reach a VCCC or VCRC processor over VME cabling in a Mark VI system, or PDIA I/O packs mounted directly on the board in a Mark VIe system.

Troubleshooting a Suspected TBCI Before Replacement

Terminal boards fail far less often than the parts around them, so verify before you buy. In a redundant system you have a useful cross-check: if only one channel — <R>, <S> or <T> — shows a bad input while the others read it correctly, the shared terminal board is almost certainly fine, so look at that channel’s pack, cable or connector instead. A point wrong on all three channels points back to the field contact or wiring. All points reading the same suggests the excitation supply. Replace the board for physical damage only: cracked blocks, burnt or corroded terminals, or heat around the suppression parts.

IS200TBCIH2BBD and the H2 Hardware Group

Reading the number: IS200 (Mark VI series), TBCI (contact-input function), H2 (hardware group), B (functional revision), and on the full string IS200TBCIH2BBD the closing BD artwork revision. GE builds the TBCI in more than one hardware group; the H1 group is documented at 125 V dc, and the H2 group is separate, so confirm your circuit’s excitation and match the group rather than assuming it interchanges with H1. Within the H2 group, IS200TBCIH2BBC and IS200TBCIH2BBD differ only by artwork revision but should still be matched exactly for keying and ID compatibility. See the GE Speedtronic Part Number Decoder.

Neighboring Boards and Migration Notes

Alongside the IS200TBCIH2B you will find its mating VCRC/VCCC VME processor or PDIA packs and the companion relay-output and analog terminal boards. If your plant is weighing a move from earlier controls, Mark V vs Mark VI: DS200 to IS200 outlines what changes between the DS200 and IS200 generations. The wider catalog of Mark VI terminations is in the GE Mark VI IS200 Boards collection.

Building an Accurate Quote Request

To quote this board precisely, provide the complete part number with suffix (IS200TBCIH2BBD), the label revision, a photo of the label, the turbine model and control generation, the quantity, and how soon you need it. Telling us whether the board runs simplex or TMR, and the excitation voltage, helps confirm the correct group.

Request a Quote for the IS200TBCIH2BBD

We deliver the IS200TBCIH2B worldwide on DDP terms, turn around quotes in 24 hours, and take purchase orders from qualified buyers. Use Request a Quote with your quantity and our team will confirm availability and lead time.

IS200TBCIH2BBD Unit Summary

General Information about the Product
Part Number	IS200TBCIH2B Mark VI IS200
Description	IS200TBCIH2B by GE IS200TBCIH2BBD Contact Input Terminal Board Mark VI IS200
Condition	used Cleaned and Tested. With 1 Year Warranty