Relay Terminal Board or Power Excitation Board? Both Names, One Card

The DS200RTBAG5AHC is unusual among GE's Mark V-era DS200 boards in that original GE instructional materials refer to it by two functional descriptions: Power Excitation Board and Relay Terminal Board. The RTBA acronym settles the question of what the hardware actually is — a relay terminal board — while the excitation name reflects where Group 5 units commonly serve, in the cabinet of a GE exciter or drive. So if one document calls your board a power excitation board and another calls it a relay terminal board, you are not looking at two different cards; you are looking at the same DS200RTBAG5A lineage this used, tested unit belongs to.

Functionally, the board is an optional addition that provides ten relays, identified K20 through K29: positions K20–K26 carry DPDT relays and the remaining three carry 4PDT types. Every relay has an LED that lights when that relay can be energized, and each is individually replaceable if defective. The board presents one 16-pin connector and one 2-pin connector for its I/O to the companion LTBA board, the relays can be driven directly from the pilot relays or remotely by the user, and field conductors land on screw-secured terminals. GE's manual for the RTBA family is GEI-100167.

Fault Isolation Before Replacement

A few habits keep RTBA troubleshooting honest — and keep good boards out of the scrap bin:

• Use the LEDs as your map. LED lit, contacts frozen: replace that one relay, not the board. LED dark: the enable is missing — chase the pilot-relay path, the connector seating, and the LTBA side before anything else.
• Respect the terminals. When removing wires, loosen the screws without backing them fully out; a screw dropped into an energized drive cabinet becomes its own outage. Clips retain the plug-compatible circuits — press the clip to release rather than pulling on the conductor.
• Kill power, then verify. Even with supply power removed, charge can linger in components. Test before touching, every time.
• Compare jumpers. The family's moveable jumpers must be set to mirror the board being replaced; factory defaults are a starting point, not a configuration.

Remember too that this board lives with the exciter or drive, not inside the Mark V <R>, <S>, <T> or <C> cores — a panel-side alarm needs tracing outward before the RTBA takes the blame.

Understanding the G5AHC Suffix

Read DS200RTBAG5AHC in four fields: DS200 for the Mark V-era series, RTBA for relay terminal board, G5 for the Group 5 configuration, and AHC for the revision block — two functional revisions, A and H, plus artwork revision C. The H revision is one GE applied comparatively rarely across this family, which is a practical reason to order by the complete string and confirm with a label photo rather than assuming any G5 will do. Group matters most — a Group 5 replaces a Group 5 — and revision letters close the match. Our GE Speedtronic Part Number Decoder covers how these fields work across every DS200 and IS200 part number.

Neighbors in the Exciter Cabinet

The RTBA's constant companion is the LTBA board, joined through the 16-pin RPL header; the two should be evaluated together whenever either is suspect. Beyond that pairing, the DS200 family spans the control, excitation, and drive electronics of the Mark V generation — the guide GE Mark V DS200 Boards Explained gives the landscape, while the GE Mark V DS200 Boards collection and the broader GE Speedtronic Turbine Control Boards range hold the boards themselves. For sites comparing continued Mark V support against a platform upgrade, Mark V vs Mark VI: DS200 to IS200 explains the successor generation's IS200 numbering and hardware.

What to Send Us for an Exact-Match Quote

• The complete part number from your label — DS200RTBAG5AHC — and a photo of the label itself.
• Which name your documentation uses (relay terminal board or power excitation board) and the equipment it serves: exciter model, drive, turbine.
• Whether your Mark V is Simplex or TMR.
• Quantity, destination country, and required delivery window.
• Urgency — a tripped unit gets handled differently than a stores replenishment.

24-Hour Quotes, Worldwide DDP Delivery

This DS200RTBAG5AHC is a used board, cleaned and tested, backed by the one-year warranty stated below. Send a Request a Quote and we reply within 24 hours. Shipping is worldwide on DDP terms, and purchase orders are accepted.