Description
DS3800NCCB1J1F: Product Overview
The DS3800NCCB1J1F is a daughterboard-grade current isolator and auxiliary interface that plugs onto a motherboard carrier inside the GE Speedtronic Mark IV rack. It isolates 24 V DC digital inputs, provides on-board RS-232/RS-485 serial ports, and stores firmware in multiple EEPROM devices, allowing the CPU to manage isolated field I/O, auxiliary serial links, and real-time parameter tables without exposing the back-plane to ground faults. Because it is hardware-deterministic (no firmware download), the card delivers bit-exact timing across all three legs of a TMR string, making it suitable for SIL-2 / API 670 current-loop and auxiliary loops.
The board belongs to the DS3800 daughterboard architecture, allowing hot-swap replacement without rewiring the turbine deck. Gold-plated edge fingers, conformal coat, and 0 °C to +60 °C rating ensure 25-year service life in coal-dust, salt-fog, or high-vibration environments.
GE DS3800HPRB1B1B
DS3800NCCB1J1F: Technical Specifications
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Model Number: DS3800NCCB1J1F
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Manufacturer: General Electric (GE)
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Product Type: Current Isolator / Auxiliary Interface Board
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System Compatibility: Speedtronic Mark IV (6BA05/06 slot)
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Logic Supply: +5 V DC @ 1 A (back-plane)
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Serial Ports: RS-232 (COM1) + RS-485 (COM2) embedded
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Supported Protocols: Modbus RTU Slave, SNP Slave, Serial I/O
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Memory: 512 program blocks, 32 k discrete I/O bits
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Crystal Oscillator: On-board for precise timing
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Trim Pots: 8 blue variable resistors (field-adjustable)
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Diodes: >70 color-coded resistors, 16 silver, 1 sand, 36 blue-green, 4 red
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Connectors: 40-pin modular (field side) + VME edge fingers (back-plane side)
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Operating Temperature: 0 °C to +60 °C; Storage: –40 °C to +85 °C
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Certifications: CE, RoHS, IEEE 344 seismic qualified
Core Features & Customer Value
Hardware-Deterministic Timing
Because the card contains no flashable firmware, every I/O bit and serial byte responds with bit-exact timing across all three legs of a TMR string. This eliminates scan-to-scan jitter that could introduce voter disagreement, giving you SIL-2 / API 670 confidence for isolated current loops and auxiliary serial links.
Because the card contains no flashable firmware, every I/O bit and serial byte responds with bit-exact timing across all three legs of a TMR string. This eliminates scan-to-scan jitter that could introduce voter disagreement, giving you SIL-2 / API 670 confidence for isolated current loops and auxiliary serial links.
Hot-Swap Ready
Daughterboard form allows you to extract and insert the card while the turbine remains on-line (provided the carrier is in a TMR string). Mean-time-to-repair is <5 minutes, so you avoid forced outages and start-up delays.
Daughterboard form allows you to extract and insert the card while the turbine remains on-line (provided the carrier is in a TMR string). Mean-time-to-repair is <5 minutes, so you avoid forced outages and start-up delays.
Field-Calibratable Without Software
On-board 8 blue trim-pots and jumper-selectable baud rate let you match RS-232/RS-485 devices or current-loop thresholds on the turbine deck using only a screwdriver and a scope. This eliminates the need for a laptop or OEM service call when you swap sensors, change cable runs, or reload firmware segments.
On-board 8 blue trim-pots and jumper-selectable baud rate let you match RS-232/RS-485 devices or current-loop thresholds on the turbine deck using only a screwdriver and a scope. This eliminates the need for a laptop or OEM service call when you swap sensors, change cable runs, or reload firmware segments.
Surge-Hardened for Harsh Sites
Multiple EEPROM modules and >70 color-coded resistors provide current capacity classification, while the crystal oscillator ensures precise frequency generation. The 1500 V galvanic isolation barrier prevents ground-fault currents from propagating into the low-voltage CPU domain, extending card life beyond 25 years in coal-dust, salt-fog, or high-vibration environments.
Multiple EEPROM modules and >70 color-coded resistors provide current capacity classification, while the crystal oscillator ensures precise frequency generation. The 1500 V galvanic isolation barrier prevents ground-fault currents from propagating into the low-voltage CPU domain, extending card life beyond 25 years in coal-dust, salt-fog, or high-vibration environments.
GE DS3800HPRB1B1B
Typical Applications
Gas Turbine Auxiliary & Serial Interface
In large combined-cycle plants, DS3800NCCB1J1F is widely used to isolate 24 V DC auxiliary contacts and to provide on-board RS-485 for remote I/O clusters or local HMIs on Frame 7/9 heavy-duty units. The 40-pin modular connector and 32 k discrete bits provide real-time visibility into crank/fire/run mode switches without external converters.
In large combined-cycle plants, DS3800NCCB1J1F is widely used to isolate 24 V DC auxiliary contacts and to provide on-board RS-485 for remote I/O clusters or local HMIs on Frame 7/9 heavy-duty units. The 40-pin modular connector and 32 k discrete bits provide real-time visibility into crank/fire/run mode switches without external converters.
Steam Turbine Current-Loop & Programming Port
The card’s embedded RS-232/RS-485 capability makes it the preferred interface for programming laptops, vibration monitors, or third-party SCADA mounted hundreds of metres from the control room, maintaining <0.1 % bit-error rate over 500 m of shielded pair.
The card’s embedded RS-232/RS-485 capability makes it the preferred interface for programming laptops, vibration monitors, or third-party SCADA mounted hundreds of metres from the control room, maintaining <0.1 % bit-error rate over 500 m of shielded pair.
Island-Mode & Black-Start Sites
On offshore platforms or remote peaking plants, the 0 °C to +60 °C rating and conformal coat allow the card to run without HVAC. Battery-backed operation is supported because the card draws <1 W and continues to relay critical auxiliary commands when the plant is islanded from the grid.
On offshore platforms or remote peaking plants, the 0 °C to +60 °C rating and conformal coat allow the card to run without HVAC. Battery-backed operation is supported because the card draws <1 W and continues to relay critical auxiliary commands when the plant is islanded from the grid.
