The Relay Output Function in a Speedtronic Panel

A GE Speedtronic Mark V energizes its field solenoids and auxiliary contacts through relays, and the DS200TCRA is the card that carries them. It provides up to thirty electromechanical plug-in relays, K1 through K30, which the control system uses to drive valve solenoids, ignition and status circuits, and interposing contacts out to the plant. Every commanded contact output on the panel ultimately closes on one of these relays.

The card belongs to the Mark V's digital I/O, not to the <R>, <S>, <T> or <C> processor cores. In a digital I/O core it is paired — usually two TCRA boards per core — with the TCDA digital I/O board that commands its coils, and the relay contacts are landed on the DTBC and DTBD terminal boards. Nothing on the board is programmable; output character (dry contact versus wetted solenoid supply) is chosen with jumpers on the terminal boards.

Confirm the Board Before You Order

Relay-output faults are one of the classic cases where the obvious suspect is the wrong one. The TCDA sinks each relay coil to common to energize it, holding the other side at a fixed voltage, so a relay that will not operate can be a TCDA driver fault or a ribbon-cable issue every bit as much as a bad relay or a bad TCRA.

• If the HMI command never shows up as commanded at the TCDA, the trouble is upstream and this board is not the fix.
• If the TCDA shows the output commanded but the contact never moves, that narrows it to the relay, the TCRA, or the ribbon between the boards.
• Before you install anything, verify the field circuit. A shorted solenoid on a 125 VDC output can burn the relay and the terminal-board traces and will take out the new card if the short remains.

The practical rule from the field is that relays wear and are replaced individually far more often than the whole board fails, and a true board failure typically follows a surge, a battery ground, or a downstream short. Establish which of those you are dealing with and you avoid buying a card you did not need.

Decoding DS200TCRAG1ACC

This board is a DS200TCRAG1A carrying the revision suffix that makes it DS200TCRAG1ACC. In that string, DS200 is the Mark V board series, TCRA is the relay-output function, G1 is the build group, and ACC is the revision level of this particular card. There is also a group 2 build (DS200TCRAG2A); since the group designation can carry hardware differences, order to the group and revision your system was built with, or confirm that a later revision supersedes yours. The GE Speedtronic Part Number Decoder walks through the format, and the definitive number is the one printed on the board.

Boards That Work Alongside the TCRA

In service the TCRA depends on several neighbors: the TCDA that drives it, the DTBC and DTBD terminal boards that carry its outputs, the TCQA analog I/O, and the TCPS that powers the core. See GE Mark V DS200 Boards Explained for how the set fits together, and the GE Speedtronic Turbine Control Boards collection for the broader range. If you are weighing a control upgrade, Mark V vs Mark VI: DS200 to IS200 explains how these functions map onto the IS200 series.

What We Need to Quote Accurately

• The full part number with revision (DS200TCRAG1ACC), taken from the board.
• A photo of the board label and silkscreen.
• Turbine model and whether the Mark V is Simplex or TMR.
• Which core the board serves and the revisions of any paired boards.
• Quantity and how soon you need it.

Request a Quote for This Board

This DS200TCRAG1ACC is a used board, cleaned and tested, with a one-year warranty. Share the details above using the Request a Quote button and we will respond within 24 hours with availability and lead time. We ship worldwide DDP and accept purchase orders.