DS3800HRMB1N1K PC Battery ROM Board (New Surplus)

Offered as new surplus in its original factory package, the DS3800HRMB1N1K is a Battery ROM board from GE's Speedtronic Mark IV DS3800 line. It is the memory card that keeps the control's program code available to the microprocessors that actually run the turbine — the reason the family is often described as the board that holds the Mark IV's firmware. As an unused spare, it is a practical way to secure an obsolete, long-out-of-production part before you need it.

The Memory Card Behind the Mark IV Processors

In a Speedtronic Mark IV, the control and protection calculations run on the triple-redundant <R>, <S>, and <T> processor sections, coordinated with the <C> communications section. Those processors do not store their own program code — they read it from the ROM modules populated on the HRMB, reaching the board through the modular connector at one end. The card also carries an on-board analog-to-digital converter, a 40-pin ribbon-cable connector, a 20-pin connector, seven jumpers, and a reset toggle switch. Physically it installs like the rest of the DS3800 set: a modular connector on one end, retention levers on the other to lock it into the rack.

Reset Switch and Ribbon Cable: Troubleshooting First

If you are commissioning this spare because an installed HRMB is misbehaving, confirm the fault before you swap:

• Use the reset toggle. It restarts the board without cutting control power. Sudden, intermittent, or undefined processing errors often trace to control signals that arrived out of sequence or were corrupted by cable interference or a minor power fluctuation — conditions a reset can clear without any new hardware.
• Reseat and re-latch the 40-pin ribbon cable. A loose or poorly routed cable is a common source of erratic behavior that imitates a failing memory board.
• Look upstream at power and the processor card. Since the HRMB only serves code to processors on other cards, verify the supply and those processors before concluding the ROM board is at fault.
• Match jumpers when you fit the spare. Set the seven jumpers to mirror the card you are replacing.

Group Code 1N1K and Why It Must Match

Read the part number as DS3800 (Mark IV series) + HRMB (Battery ROM function) + 1N1K (the group code fixing this exact version and revision). On the HRMB, the group code is the critical field: different codes across the family carry different components and firmware, so the suffix must match the installed board — and the memory content has to suit your application. Our GE Speedtronic Part Number Decoder explains how the segments line up.

Related Mark IV Memory and Processor Boards

Because a ROM board only makes sense next to the processors it feeds, many buyers source it alongside other DS3800 cards. Browse the set in our GE Mark IV DS3800 Boards collection or the wider GE Speedtronic Turbine Control Boards range.

Request a Quote on This New-Surplus HRMB

Send the complete part number with the 1N1K suffix, a photo of the board label including any firmware or EPROM markings, the jumper configuration if known, your turbine model, Mark generation, quantity, and how soon you need it. We will confirm the match and availability, respond within 24 hours, ship worldwide DDP, and accept purchase orders.