DS200DCFBG2BLC: A G2-Group Power Supply Board

DS200DCFBG2BLC is a G2-group DCFB, GE's Power Supply Board used in the EX2000 excitation control system and shared, with some circuit differences depending on application, across the DC2000, AC2000, CB2000, FC2000, GF2000, and ME2000 IGBT drive families. It delivers control-level power to the drive or exciter and 115 VAC to the enclosure cooling fans, using 38 VAC and 115 VAC input from the control power transformer (CPT). Onboard circuitry includes control-level power supplies (+5 V, ±15 V, ±24 V), motor/generator field power circuits, driver circuits for the armature SCR gate pulse generators, and instrumentation circuits monitoring AC line current and voltage.

The DCFB works directly with the SDCC drive control card (or LDCC on EX2000 systems), exchanging feedback and power-good signals over the 1PL and 2PL connectors. The 38 VAC input from the CPT is rectified and filtered into ±24 VDC (+24 V at 3 A, -24 V at 1 A), from which onboard regulators derive ±15 VDC, and the +24 VDC rail also produces a +5 VDC, 4 A output that the drive control card's microprocessor depends on to keep running. Voltage-controlled oscillator (VCO) circuits on the board convert several analog signals – SCR bridge input voltage, output bridge voltage, and shunt-derived current signals – into frequency feedback (nominally 250 kHz, ranging 0–500 kHz) sent to the SDCC/LDCC over connector 1PL.

Diagnose Before You Order a Replacement

A DCFB fault and an SDCC/LDCC fault often present identically at the operator interface, because the DCFB's /PSEN signal on 2PL is what keeps the drive control card's microprocessor running: it sits TTL-low when the +5 VDC output is properly regulated, and goes high – forcing a reset – the moment that rail sags. A drive or exciter resetting on its own can be a DCFB symptom wearing a drive-control-card costume. Before replacing either board:

• Check the DCFB's fuse-status indicators first. LEDs CR51 and CR55 flag a blown FU2 or FU3 (7 A power-output fuses); a neon lamp LT1 flags a blown FU1 (1/2 A, on the 115 VAC fan output).
• Verify the +5 V and ±24 V rails feeding the SDCC/LDCC before assuming its own microprocessor or logic has failed.
• Treat a repeat failure in the same slot as a downstream problem first. Experienced Mark V/EX2000 technicians consistently report that a card position failing again and again usually points to a field device, wiring, voltage, or current problem – not a bad batch of boards.
• Consider the companion drive control card. There are documented cases of a DCFB and its companion LDCC failing together where a burnt capacitor on the LDCC turned out to be the real cause. GE never released full schematics for this card generation, so an experienced repair shop with card-level test equipment is often the fastest path to a confirmed root cause.

What G2BLC Means

DS200 is the board series prefix, DCFB is the Power Supply Board acronym, G2 is this board's product grouping, and BLC is the specific functional and artwork revision combination. GE's manual reference for this board is GEI-100028 (later documented under GEI-100028C). We haven't found a confirmed functional split between G1 and G2 DCFB groups comparable to the exciter distinction seen on some other DS200 board families, so treat the group letter as a hardware/manufacturing revision and always match the full suffix on the card you're replacing.

Related Boards and Longer-Term Alternatives

The DCFB pairs closely with the SDCC (or LDCC on EX2000) drive control card and the panel's TCPS power supply. For sites weighing a longer-term platform change, see our Mark V vs Mark VI: DS200 to IS200 guide. For the mechanics of GE's Speedtronic part numbering, see the GE Speedtronic Part Number Decoder, and for the DCFB's place among the other DS200 boards, see GE Mark V DS200 Boards Explained.

What to Send With Your Quote Request

• The complete part number and suffix, e.g., DS200DCFBG2BLC
• A photo of the label
• Turbine/generator model, and whether this feeds an EX2000 exciter or a DC2000/AC2000-family drive
• Quantity needed
• Urgency – planned outage or active fault

Request a Quote

This DS200DCFBG2BLC is offered used, clean and tested, with a 1-year warranty (see below). Pricing isn't published online since these quotes depend on exact revision match and current stock – submit a Request a Quote and expect a 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	DS200DCFBG2B Mark V DS200
Description	DS200DCFBG2B By GE DS200DCFBG2BLC DC2000 AC2000 EX2000 Power Supply Board
Condition	used Clean and Tested With 1 Year Warranty.