DS3800NFCD1H1D | GE Speedtronic Fiber Optic Comm Board

Description

Product Introduction

The DS3800NFCD1H1D is the most powerful fiber optic communications board GE ever produced for the Mark IV—a board designed to connect control cabinets across entire power plant campuses, industrial sites, and even between adjacent facilities. The suffix tells the story: the first “1” is a hardware revision with an avalanche photodiode receiver for extended sensitivity. The “H” specifies the highest-power 1300nm long-wave transceivers with a 22dB optical budget. The second “1” adds the full diagnostic suite (optical power monitoring, link quality trending, and error logging). The final “D” is the military-grade environmental package: triple-layer conformal coating, hermetically sealed components, and MIL-STD-810G shock/vibration tolerance. This board was designed for critical infrastructure where fiber links exceed 5km—or where environmental conditions are extreme enough to kill standard boards.

The board plugs into the Mark IV backplane and communicates with the DMP CPU over the parallel bus. The 1300nm transceivers with APD receivers operate at the Mark IV bus limit of 2Mbps and support fiber runs up to 8km on 62.5/125µm multimode fiber. Compare this to the standard NFCD (850nm, 2km range, basic diagnostics). The 1H1D gives you four times the reach, military-grade environmental protection, and an advanced diagnostic system that can predict link failure before it happens. If you’re running links across a large site or in a harsh environment, this is the board that gives you peace of mind.

Key Technical Specifications

Compatible Replacement Models

Frequently Asked Questions (FAQ)

What’s the difference between the 1H1D and the 1G1H?
The 1G1H uses 1300nm transceivers with a 22dB optical budget and standard PIN photodiodes. The 1H1D uses the same 1300nm transceivers but adds an APD (avalanche photodiode) receiver, which is more sensitive and gives you the additional optical budget. The APD requires a higher bias voltage (hence the higher +12V current draw). The practical result: the 1H1D gives you 8km range versus the 1G1H’s 5km. The 1H1D also adds the military-grade coating and shock/vibration tolerance.

Can I use this board with single-mode fiber?
The 1H1D is designed for multimode fiber (62.5/125µm) with ST connectors. The APD receiver is sensitive enough to work with single-mode fiber in some cases, but the transceivers are LED-based—they weren’t designed for single-mode coupling. You’ll likely get 2-3km range on single-mode fiber, which defeats the purpose of the board. Use multimode fiber for full performance.

Do I need to upgrade my DMP firmware for this board?
The APD bias control and predictive diagnostics require DMP firmware v4.0 or later. If you’re running an older firmware version (v3.x), the board will still work as a fiber link, but the APD bias might not be optimal and the diagnostics won’t be available. We can provide the firmware EPROMs for the upgrade if needed. The firmware upgrade takes about an hour.

What’s the APD bias status LED?
The APD (avalanche photodiode) requires a high-voltage bias (typically 40-60V) to operate correctly. The APD Bias Status LED indicates that the bias voltage is within specification. If the LED is red, the bias voltage is out of range—the board may not achieve full sensitivity, and the link budget will be reduced. This can happen if the backplane +12V rail is low. Check your power supply if you see a red APD Bias LED.

How does the predictive failure alert work?
The 1H1D continuously monitors the received optical power and the link error rate. It stores the historical data and calculates a trend. If the optical power drops by more than 3dB over a rolling 30-day period, the board logs a “Link Degradation” warning. This gives you weeks of advance notice that your fiber link is degrading due to connector contamination, aging fiber, or splice degradation. In practice, this has allowed plants to schedule fiber maintenance during planned outages instead of reacting to unplanned link failures. The trend data is accessible through the diagnostic registers.

Is the fiber link redundant?
The board has two channels (A and B), but they’re independent links to two different remote nodes. The Mark IV doesn’t automatically fail over from one channel to the other. If you need redundancy, you’d need two NFCD boards in separate CPU racks or a different architecture. The diagnostic features apply to both channels independently.

Can I hot-swap this board?
No. Mark IV backplanes are not hot-swappable. Power down the cabinet, lock out the breaker, and wait 60 seconds before removing or installing the board.

What’s the most common failure mode on the NFCD1H1D?
We’ve serviced only a handful of these boards—they’re extremely reliable. The most common failure is the APD bias voltage supply—it’s a DC-DC converter on the board that can fail after 15-20 years. The symptom is a red APD Bias LED and a link that’s intermittent or has reduced range. We replace the DC-DC converter module. The second most common failure is the edge connector. The board is repairable.

What’s your warranty and lead time?
The NFCD1H1D is a rare board. We typically have 1-2 units in stock. Lead time is 3-5 business days for testing and verification. We offer a 1-year warranty on functional defects. We test every board with a 48-hour burn-in, a fiber optic loopback test (with a spool of 8km fiber), a diagnostic verification (optical power monitoring, predictive alert test), and a thermal cycle (-40°C to +85°C). The test report is included.

Can I use this board with the DS3800NFCD in the same system?
Yes, as long as the remote nodes are configured correctly. The 1H1D can communicate with standard NFCD boards—the protocol is the same. However, the link range is limited by the standard board’s receiver (-22dBm). The maximum practical distance with a standard NFCD at one end is about 2.5km. To get the full 8km range, you need the 1H1D at both ends.

What’s the difference between this board and the Mark IV NECA Ethernet board?
The NFCD1H1D is a fiber optic serial link board—it’s for point-to-point, isolated, high-reliability communication between Mark IV cabinets. The NECA is an Ethernet board for plant-wide TCP/IP networks. They’re different tools for different purposes: the NFCD for dedicated control links, the NECA for data logging and remote monitoring. They’re not interchangeable.