Description
DS3800NDID1P1A: Product Overview
The DS3800NDID1P1A is a daughterboard-grade D/A converter that occupies a 6BA09 slot in the GE Speedtronic Mark IV rack. It receives parallel digital words (speed demand, temperature bias, load set-point) from the CPU over the VME back-plane, converts them to precise analog voltages or currents, and drives servo amplifiers, IGV positioners, and remote indicators throughout the turbine island. The card is hardware-configured (no firmware) and deterministic, making it suitable for safety-related control loops when triple-redundant.
Physical implementation includes precision DACs, op-amp output stages, galvanic isolation, and TVS surge suppressors. 20-pin ribbon connectors (input and output) mate with the carrier motherboard; keyed and gold-plated to prevent mis-insertion or fretting corrosion. Front-edge LEDs (green = output active, red = over-range or fault) give real-time channel health—no multimeter required during commissioning.
Environmental qualification meets –20 °C to +70 °C and CE certification, permitting installation in turbine auxiliaries or control rooms with minimal HVAC. MTBF is >250 000 h at 55 °C, giving >20-year service life in baseload duty.
GE DS3800HPRB1B1B
DS3800NDID1P1A: Technical Specifications
-
Model Number: DS3800NDID1P1A
-
Manufacturer: General Electric (GE Energy)
-
Product Type: Digital-to-Analog Output Card (DAC)
-
System Compatibility: Speedtronic Mark IV (6BA09 slot)
-
Output Ranges:
-
Current: 4–20 mA (live zero) or 0–20 mA (jumper-selectable)
-
Voltage: 0–10 V (jumper-selectable)
-
-
Resolution: 12-bit monotonic, ±½ LSB INL
-
Settling Time: <5 µs to ±0.1 % for 10 V step
-
Load Capability: 750 Ω (current mode), 5 kΩ (voltage mode)
-
Isolation: 1500 V AC channel-to-ground, 500 V channel-to-channel
-
Update Rate: 100 kHz max (jumper-selectable 1 kHz, 10 kHz, 100 kHz)
-
Trimmers: Offset and gain pots per channel (front-access)
-
Connectors: 20-pin ribbon, keyed, gold-plated
-
Power Rails: +5 V logic, ±15 V analog, <1 W per channel
-
LEDs: Green = output active, Red = over-range / fault
-
Temp Range: -20 °C to +70 °C operational, -40 °C to +85 °C storage
-
Certifications: CE, RoHS, Mark IV form-factor compatible
Core Features & Customer Value
Microsecond-Fast Settling for Servo Loops
<5 µs settling to 0.1 % enables 10 kHz servo-loop bandwidth—critical for IGV positioners and fuel-metering servo valves that must track speed/load transients without overshoot.
<5 µs settling to 0.1 % enables 10 kHz servo-loop bandwidth—critical for IGV positioners and fuel-metering servo valves that must track speed/load transients without overshoot.
Hot-Swappable in TMR Strings
Redundant Mark IV allows online replacement of one DAC card; remaining two legs continue voting. MTTR is <5 min—no outage, no load shed, no restart required.
Redundant Mark IV allows online replacement of one DAC card; remaining two legs continue voting. MTTR is <5 min—no outage, no load shed, no restart required.
Field-Calibrated Without Software
Offset and gain trimmers compensate for valve hysteresis, cable resistance, or amplifier drift—technician can trim full-scale and zero using only a screwdriver and a DMM, reducing commissioning time by >50 %.
Offset and gain trimmers compensate for valve hysteresis, cable resistance, or amplifier drift—technician can trim full-scale and zero using only a screwdriver and a DMM, reducing commissioning time by >50 %.
Surge-Hardened for Turbine Deck
TVS diodes and opto-isolators clamp >500 V spikes from servo amplifiers or lightning. 1500 V isolation prevents ground-fault propagation to CPU cards, reducing unplanned replacement by >60 % compared with non-isolated DACs.
TVS diodes and opto-isolators clamp >500 V spikes from servo amplifiers or lightning. 1500 V isolation prevents ground-fault propagation to CPU cards, reducing unplanned replacement by >60 % compared with non-isolated DACs.
GE DS3800HPRB1B1B
Typical Applications
Gas Turbine Fuel & IGV Control
Drives ±10 V input to Woodward servo amplifiers for fuel-metering valves and IGV hydraulic actuators in Frame 7/9 units. 12-bit resolution achieves 0.025 % fuel-flow accuracy, essential for NOx compliance and part-load heat-rate optimization.
Drives ±10 V input to Woodward servo amplifiers for fuel-metering valves and IGV hydraulic actuators in Frame 7/9 units. 12-bit resolution achieves 0.025 % fuel-flow accuracy, essential for NOx compliance and part-load heat-rate optimization.
Steam Turbine Governor & Extraction Control
4–20 mA output drives Moog servo valves on governor and extraction pressure loops. Deterministic update rate prevents valve dither and mechanical wear, extending servo life to >100 k hours.
4–20 mA output drives Moog servo valves on governor and extraction pressure loops. Deterministic update rate prevents valve dither and mechanical wear, extending servo life to >100 k hours.
Remote Indication & DCS Interface
0–10 V scaled signals feed plant DCS for remote load meters, temperature indicators, and vibration displays. Isolation eliminates ground-loop noise that would corrupt 4–20 mA loops in large combined-cycle sites.
0–10 V scaled signals feed plant DCS for remote load meters, temperature indicators, and vibration displays. Isolation eliminates ground-loop noise that would corrupt 4–20 mA loops in large combined-cycle sites.
