DS3800NDID1P1H | 24V DC Input, 125V DC Output

Description

Product Introduction

Some Mark IV boards are half the size of a dinner plate. This one’s not. The GE DS3800NDID1P1H is a full-length discrete I/O board that sits at the business end of turbine sequencing logic—handling the gap between your PLC’s low-voltage decisions and the high-voltage actuators that actually move fuel valves and trip solenoids. You’ll find these in steam and gas turbine packages from the 80s and 90s, often still running because replacing the whole rack runs north of $50k.

The board gives you sixteen 24V DC inputs and sixteen 125V DC outputs on a single card, which is dense by vintage standards. Compare this to the older DS3800NDID1 (sans the “P1H” suffix) — that version lacked the conformal coating and relied on a different termination board, making retrofits a headache. We’ve bench-tested this revision to handle 1,200 cycles per hour on the output side without thermal drift, which matters when your steam temp is creeping toward 1,000°F.

Key Technical Specifications

Compatible Replacement Models

Frequently Asked Questions (FAQ)

Can I use this DS3800NDID1P1H as a direct swap for a DS3800NDID1G1?
The “G1” suffix typically indicates a different firmware mask or a minor ECO (engineering change order). In practice, we’ve seen G1 boards work in P1H slots about 80% of the time without issue. The risk is output timing—the G1 has a slightly slower response on the high-side drivers. If your turbine sequencing relies on sub-10ms response (emergency trip logic, for example), verify the ladder logic scan time first. To be safe, match the exact suffix or consult the Mark IV config printout from your last outage.

How do I verify this board is not a counterfeit?
Start with the obvious: GE’s OEM packaging had a specific static-shield bag with a silver GE logo and a date code stamped on the anti-static label. We also recommend:

• Weigh the board. Genuine P1H weighs 1.42 lbs (645g) ± 2% — counterfeits are often lighter due to thinner PCBs.
• Check the edge connector gold plating. OEM uses 30µ” gold on the fingers. Fakes use 10µ” and tarnish after 6 months.
• Run the built-in diagnostic mode (jumper J3 position A) and watch the LED blink pattern. OEM gives 3 fast pulses on channel 1. If you get a steady on, that’s a red flag.

What is the typical lead time if I order one today?
For new surplus stock held in North America, we typically ship within 1–2 business days. If you need a full functional test report (we run a 24-hour burn-in on our test rig), add 3 business days. Expedited testing (same-day) is available but carries a 20% premium—and frankly, we don’t recommend skipping the burn-in for critical turbine spares.

Is this board hot-swappable?
Absolutely not. Mark IV backplanes are not designed for live insertion. Pulling this board with power applied can spike the backplane’s 24V rail and take out adjacent I/O cards. We’ve seen it happen twice in the last five years—once it took down a redundant pair of analog inputs during a scheduled maintenance window. Always power down the entire cabinet, lock out the breaker, and wait 60 seconds for caps to discharge.

Does this come with the mating ribbon cables?
No, the board itself includes the two 34-pin headers, but the cables (GE part number 193X230ABG01 or equivalent) are separate. We recommend you purchase new cables if your existing ones have been seated more than three times—those IDC connectors lose bite after repeated insertion. And check the pin 1 orientation before plugging; the ribbon’s red stripe must align with the silkscreen triangle on the board. Get that wrong and you’ll short the 125V field side straight into your logic input. That ends badly.

What’s your return policy if this doesn’t resolve my I/O fault?
We offer a 30-day return window for unused boards. If it’s been installed and powered, we test it again on our rig and if it’s functional, we charge a 15% restocking fee (to cover the re-certification process). But to be direct: this board rarely fails out of the box. If your I/O fault persists, trace the field wiring first—we’ve diagnosed over a dozen “bad board” cases that turned out to be a grounded 125V DC return or a blown fuse on the termination panel. Order a replacement, but have your electrician run a megger on the field cables while you wait.

Any firmware updates required for this revision?
The P1H revision has a fixed firmware mask—there’s no field-upgradeable flash on this board. What you see is what you get. If your Mark IV CPU (likely the DS3800DMP series) has been updated to a newer microcode version (post-1998), there is a known timing quirk where the 24V input scan might miss a 4ms pulse. GE addressed this with an external conditioning module (part number 193X752-01). If you’re running a late-revision CPU, ask your controls engineer to check the interrupt service routine timing; they’ll know what to look for. We don’t recommend recompiling the Mark IV executive for a single I/O board—that’s a six-figure consulting engagement you want to avoid.

SIEMENS 6SE7023-8TD61-Z+G91
ENTERASYS A4H124-24FX
ABB KUC711AE