DS200TCDAH1BJE: Role in the Mark V Panel

Ask any technician who has worked a Mark V outage and they'll tell you the TCDA is the card behind most contact-input and relay-output alarms. DS200TCDAH1BJE is an H1-group TCDA: it carries field contact signals (limit switches, permissives, status points) into the control logic, and drives relay outputs to contactors, solenoids, and annunciator circuits on the way back out. Whether a given terminal is an input or an output is defined in software, not by the card's physical construction.

This board is installed in one of the Mark V's control cores – <R>, <S>, or <T> in a TMR panel, or the single core in a Simplex panel – and TCDA also shows up in the documented card set of the <C> communication core on many systems. It works alongside a companion relay board (TCRA) and I/O cards such as TCQA, TCQE, and TCEA over the panel's IONET.

What to Rule Out Before You Order a New TCDA

Plenty of "failed TCDA" diagnoses turn out to be something else once someone checks further. Documented Mark V field cases attribute classic TCDA symptoms – continuous I/O state cycling, repeated card-lost alarms after a trip – to causes such as:

• IONET termination resistors set wrong. Termination should sit IN at the TCDA and OUT on every TCEA card in the loop; one TCEA out of position reproduces the exact fault of a bad TCDA.
• The TCPS supply feeding the core, rather than the TCDA – check its output rails before condemning the card.
• Ripple or spikes on the DC control bus, from a battery charger or from de-energizing unsuppressed DC coils near the cabinet.
• An unresolved firmware/PROM revision, since GE has fixed certain IONET communication faults with a PROM upgrade rather than a hardware swap.
• A loose card or corroded connector pin.

Also keep the TCDA distinct from its relay-output partner, TCRA, when you're troubleshooting: TCRA's relays are electromechanical and wear through switching cycles, while the TCDA doesn't share that failure path. A relay output that won't energize is more often a TCRA fault. On lifespan, there's no fixed replacement interval – many TCDA cards run eight-plus years without trouble, and general Mark V experience puts mean time between failures in the low hundreds of thousands of hours, with cabinet heat, humidity, dust, and voltage transients causing most real failures rather than age by itself.

Reading This Part Number

DS200 is the Mark V-era series prefix, TCDA is the Digital I/O function, H1 is this board's product grouping, and BJE encodes its specific functional and artwork revision levels. H1 and G1 are separate TCDA hardware groupings, not simply older and newer versions of the same board, so verify which grouping your Mark V documentation specifies rather than assuming interchangeability. Order and quote against the complete string, DS200TCDAH1BJE.

Related Boards and the Mark VI Alternative

TCDA is usually discussed together with TCRA, TCQA, TCQE, TCEA, STCA, and UCPB. If your plant is looking at a longer-term platform change, GE's Mark VI system replaced the DS200 series with IS200-series boards under a different I/O architecture; see our Mark V vs Mark VI: DS200 to IS200 guide. For the structure behind GE's Speedtronic part numbers, see the GE Speedtronic Part Number Decoder, and for how TCDA fits with the rest of the DS200 lineup, see GE Mark V DS200 Boards Explained.

What to Send With Your Quote Request

• The full part number and suffix, e.g., DS200TCDAH1BJE
• A photo of the label
• Turbine model and Mark V configuration (Simplex or TMR)
• Quantity needed
• Whether this is urgent or for planning

Request a Quote

This DS200TCDAH1BJE is offered used, clean and tested, with a 1-year warranty (details below). We don't publish pricing online since Mark V board quotes depend on exact revision match and current availability – send a Request a Quote and our team will reply within 24 hours. We ship worldwide DDP, accept purchase orders, and support both planned outages and urgent turbine-down orders.

General Information about the Product
Part Number	DS200TCDAH1B Mark V DS200
Description	GE DS200TCDAH1B DS200TCDAH1BJE Digital I/O Board Mark V
Condition	used Clean and Tested. With 1 Year Warranty.