Description
DS380DISA1A1B Product Overview
The DS380DISA1A1B is a signal-isolated auxiliary board that plugs into GE Mark IV turbine and EX2000 exciter control racks. Occupying a 6BA Euro-card slot, it acts as a compact field I/O buffer: it accepts up to six dry-contact or 24 Vdc inputs, opto-isolates each channel, and presents the resulting status word to the main CPU over the NDIA parallel bus. Because all copper traces are fully encapsulated in high-temperature epoxy, the unit is treated as a line-replaceable module—any internal fault requires a complete card swap rather than component-level rework. The module is fully hot-swappable when the rack is powered down, and its low-profile epoxy package allows adjacent-slot population without additional cooling.
The DS380DISA1A1B is a signal-isolated auxiliary board that plugs into GE Mark IV turbine and EX2000 exciter control racks. Occupying a 6BA Euro-card slot, it acts as a compact field I/O buffer: it accepts up to six dry-contact or 24 Vdc inputs, opto-isolates each channel, and presents the resulting status word to the main CPU over the NDIA parallel bus. Because all copper traces are fully encapsulated in high-temperature epoxy, the unit is treated as a line-replaceable module—any internal fault requires a complete card swap rather than component-level rework. The module is fully hot-swappable when the rack is powered down, and its low-profile epoxy package allows adjacent-slot population without additional cooling.
GE DS3800HSDD1F1G
DS380DISA1A1B Technical Specifications
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Model Number: DS380DISA1A1B
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Manufacturer: General Electric (GE Fanuc)
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Product Type: Signal Isolated Auxiliary / Field I/O Buffer Board
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Series: DS3800, Mark IV Speedtronic
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Field Connections: 6 quick-connect screw terminals (2-row layout)
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Input Type: Dry contact or 24 Vdc (jumper-selectable wetting voltage)
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Isolation: 1500 Vdc channel-to-ground; opto-coupled status lines
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Update Rate: 2 ms (scanned by CPU every control interval)
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Power Demand: +5 V @ 0.4 A, +15 V @ 0.1 A from rack 2PL bus
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Operating Temperature: 0 – 60 °C
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Weight: ≈ 0.22 kg
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Construction: Epoxy-sealed copper traces—non-repairable
Core Features & Customer Value
Six-Point Isolated I/O: The on-board opto-isolators accept both dry contacts and 24 Vdc signals on the same terminal strip. For the maintenance engineer this eliminates the need for external wetting supplies or separate 24 V input cards, reducing wiring complexity and spare-part count.
Epoxy-Sealed Construction: All internal copper is encapsulated in high-temperature epoxy. In coastal or industrial sites with conductive dust and high humidity the seal prevents trace-to-trace shorting that would otherwise cause random “AUX SIGNAL FAIL” alarms after ten-plus years of service. The trade-off is non-repairability—any internal fault requires a whole-card exchange—but this is offset by reduced troubleshooting time and the fact that plants stock one spare instead of maintaining a repair bench.
Quick-Connect Field Terminals: The six screw terminals use a two-row quick-connect pattern that accepts standard 0.25 in. push-on lugs. For field technicians this means faster wire installation and lower torque requirements compared with traditional screw-clamp blocks, cutting replacement time to under three minutes.
GE DS3800HSDD1F1G
Typical Applications
In combined-cycle power plants the board is installed in the Mark IV turbine control core where it lands the status of auxiliary cooling-fan contactors, fire-gas limit switches, and torque-limit relays. The on-board opto-isolators keep 480 V switching transients from walking into the 5 V CPU data bus.
On utility-scale EX2000 static exciters the same card is used to monitor the brushless-exciter diode-fail contacts and the field ground-detector relay. Because the inputs are group-isolated, a shorted contactor coil will not drag down the entire digital I/O rack.
Frequently the same part number is used on mechanical-drive gas compressors to land the status of inlet-guide-vane limit switches and lube-oil pressure switches. Its ability to mix dry contacts and 24 Vdc inputs on one card makes it a universal “auxiliary status” buffer for any Mark IV loop that needs deterministic, contactor-level feedback.
