GE DS3800HHTB

Parameters

• I/O Type: Discrete input (24V DC) / relay output (Form C, configurable)

• Channels: 8–16 relay outputs + 8–16 discrete inputs (hybrid configuration)

• Input Voltage: 24V DC (nominal), 10–30V DC range

• Output Rating: Relay – 5A @ 120V AC / 3A @ 24V DC (higher than HHR series)

• Isolation: 2500V RMS optical isolation (inputs) / 1500V RMS (relay contacts)

• Power: +5V DC @ 1.0A, +24V DC @ 1.0A (field power for relays)

• Response Time: 10ms input scan, 15ms output relay actuation

• Coating: Basic conformal coating (suffix B) – single-layer acrylic

• Temp Range: 0°C to +60°C

• Mounting: 6U VME Eurocard, single-slot

• Diagnostics: LED status per channel (input and output)

Advantages & Features

• Higher current relay outputs (5A) allow direct driving of solenoids and contactors without external interposing relays

• Hybrid I/O configuration – combines inputs and relay outputs on a single board, saving cabinet space

• Optical isolation protects the backplane from field wiring faults and surges

• Form C relay contacts (NO/NC) provide flexibility for fail-safe and trip circuit designs

• Compatible with Mark IV backplanes and some VIe systems (with adapter)

• Front-panel LEDs for per-channel status indication

• Hot-swappable (with proper backplane support)

Application Cases

• Turbine fuel and steam solenoid valve control (high-current direct drive)

• Emergency trip system (ETS) logic with relay outputs for shutdown valves

• Annunciator panel driver with high-current alarm indicators

• Speedtronic Mark IV I/O expansion for Frame 5/6B/7EA gas turbines requiring high-current outputs

• Retrofit replacing obsolete DS3800H series discrete boards

Competitor Comparison

• vs. DS3800HHRB (HHR series): Higher output current (5A vs. 2A relay or 0.5A transistor), but fewer I/O channels (16 vs. 32) – HHTB is better for direct high-current load driving

• vs. DS3800HMPB (Mark IV output board): Higher current capacity and hybrid I/O (input + output) vs. fixed output only

• vs. ABB DSDI series: Higher relay output current, but ABB offers PROFIBUS/Modbus communication options

• vs. Siemens 6ES7 series: Higher current capacity, but GE Mark IV backplane integration is more seamless for existing Speedtronic cabinets

• vs. Woodward 5437 modules: Higher current rating and hybrid I/O, but Woodward offers more flexible configuration software

• vs. Honeywell 51304638 : Higher output current capability, but Honeywell offers better long-term contact reliability

Selection Suggestions

• Confirm your backplane provides both +5V and +24V field power with sufficient current capacity (+24V @ 1.0A)

• Assess output current requirements – HHTB supports up to 5A, suitable for direct solenoid/contactor drive

• Determine I/O mix – hybrid configuration reduces board count for applications requiring both inputs and outputs

• Evaluate environmental conditions – basic coating (B) is for clean, dry indoor installations

• Order mating front connector (p/n may vary – confirm with GE)

• For critical applications, consider used/refurbished units with 90-day warranty

Precautions

• Critical: Confirm output current rating – do not exceed 5A per relay channel (AC) or 3A (DC)

• Critical: Relay outputs are Form C (NO/NC) – verify wiring to normally open or normally closed contacts based on fail-safe requirements

• Use shielded cables for input wiring to avoid EMI – especially near VFDs or large transformers

• Ensure field power supply (+24V DC) is stable and within 10–30V DC range

• Basic coating (B) does not protect against humidity or corrosive gases – upgrade to C/D/G/H if needed

• Store in ESD-safe packaging – the edge connector is static-sensitive

• Periodically check output relay contact wear – replace board if contacts show signs of pitting or welding

• Do not hot-swap – Mark IV backplanes require power-off for insertion/removal

• Verify turbine control logic supports the I/O mapping of this board – older cabinets may have addressing limitations

• If replacing a similar board, confirm pinout compatibility – HHT series may have different wiring assignments than HHR or HFP series