Description
DS3800HRCA1D1B: Product Overview
The DS3800HRCA1D1B is a daughterboard-level signal conditioner that plugs onto a motherboard carrier inside the Mark IV rack. It sits electrically between the field terminal blocks and the A/D or frequency-counter cards, providing gain, offset, filtering, and isolation for low-level sensor signals. Typical inputs include magnetic speed pickups, RTDs, 4–20 mA loops, and ±50 mV thermocouples; outputs are 0–10 V or 0–20 mA levels compatible with the Mark IV data converters.
The card uses a 20-pin ribbon to receive raw field signals and a second 20-pin ribbon to deliver conditioned signals to the next stage. Three precision trimmers (gain, offset, filter) per channel allow field calibration without removing the card. 1500 V AC galvanic isolation breaks ground loops and VFD noise common on turbine decks. Conformal coat and gold-plated edge fingers ensure 25-year life in salt-laden or high-dust environments.
Because it is a daughterboard, the HRCA1D1B is hot-swappable when used in redundant Mark IV configurations: power-down the carrier, extract the daughterboard, insert the replacement, and re-trim—no re-wiring and no software reload required.
DS3800HRCA1D1B
DS3800HRCA1D1B: Technical Specifications
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Model Number: DS3800HRCA1D1B
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Manufacturer: General Electric (GE Energy)
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Product Type: Signal Conditioning Daughterboard
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Function: Analog & digital signal amplification, filtering, scaling, isolation
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Input Range: ±50 mV to ±10 V, 4–20 mA, 0–1 kΩ RTD, magnetic pickup (5–120 V p-p)
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Output Range: 0–10 V, 0–20 mA, TTL/CMOS logic levels (jumper-selected)
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Isolation: 1500 V AC channel-to-ground, 500 V channel-to-channel
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Accuracy: ±0.1 % span @ 25 °C (±0.25 % over -40–85 °C)
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Filter: 2-pole Butterworth, 10 Hz to 10 kHz jumper-selectable
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Trimmers: 3 per channel (gain, offset, filter corner)
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Connectors: 2 × 20-pin ribbon (input & output), keyed, gold-plated
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Power Rails: ±15 V DC (from rack), +5 V DC logic, <1 W per channel
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Environmental: -40 °C to +85 °C operational, IEEE 344 seismic, 95 % RH non-condensing
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MTBF: >300 000 h @ 55 °C (IEC 61709)
Core Features & Customer Value
Plug-and-Play Daughterboard Form Factor
No back-plane rewiring—the 20-pin mezzanine interface mates with the carrier motherboard; swap the card, re-trim, and return to service in <5 min. Gold-plated fingers eliminate fretting corrosion common in high-vibration compressor buildings.
No back-plane rewiring—the 20-pin mezzanine interface mates with the carrier motherboard; swap the card, re-trim, and return to service in <5 min. Gold-plated fingers eliminate fretting corrosion common in high-vibration compressor buildings.
Field Calibration Without Software
Three front-access trimmers per channel allow gain, offset, and filter adjustment using only a screwdriver and a DMM. Document the original screw position before change; restore baseline instantly if site conditions change (e.g., sensor replacement, cable lengthening).
Three front-access trimmers per channel allow gain, offset, and filter adjustment using only a screwdriver and a DMM. Document the original screw position before change; restore baseline instantly if site conditions change (e.g., sensor replacement, cable lengthening).
1500 V Isolation Stops Ground-Loop Damage
Galvanic isolation protects sensitive A/D converters from VFD common-mode spikes and lightning-induced surges. Insurance audits recognise this as a risk-reduction measure, lowering premium categories for critical-infrastructure sites.
Galvanic isolation protects sensitive A/D converters from VFD common-mode spikes and lightning-induced surges. Insurance audits recognise this as a risk-reduction measure, lowering premium categories for critical-infrastructure sites.
Seismic & Harsh-Site Qualified
IEEE 344 Class 1 qualification permits mounting directly on the turbine deck with no extra HVAC. Conformal coat resists salt fog and SO₂ in coastal or refinery environments, extending replacement interval to >20 years.
IEEE 344 Class 1 qualification permits mounting directly on the turbine deck with no extra HVAC. Conformal coat resists salt fog and SO₂ in coastal or refinery environments, extending replacement interval to >20 years.
DS3800HRCA1D1B
Typical Applications
Gas Turbine Speed & Temperature Channels
Conditions magnetic speed pickups (5–120 V p-p) and Type K thermocouples (±50 mV) before frequency-counter and A/D cards in Frame 7/9 units. 10 Hz filter removes gear-mesh noise while preserving overspeed transients.
Conditions magnetic speed pickups (5–120 V p-p) and Type K thermocouples (±50 mV) before frequency-counter and A/D cards in Frame 7/9 units. 10 Hz filter removes gear-mesh noise while preserving overspeed transients.
Steam Turbine Vibration & Eccentricity
Amplifies 3500 proximity-probe signals (200 mV/mil) to 0–10 V levels for 3500/42M monitors. 1500 V isolation breaks ground loops between turbine deck and control room, preventing false vibration trips.
Amplifies 3500 proximity-probe signals (200 mV/mil) to 0–10 V levels for 3500/42M monitors. 1500 V isolation breaks ground loops between turbine deck and control room, preventing false vibration trips.
Auxiliary Systems & Interposing Logic
Converts 24 V DC limit-switch inputs to TTL for PLC interface and drives interposing relays for fuel-valve solenoids. Dual-rail ±15 V supplies allow bipolar output for legacy servo amplifiers without external DC/DC converters .
Converts 24 V DC limit-switch inputs to TTL for PLC interface and drives interposing relays for fuel-valve solenoids. Dual-rail ±15 V supplies allow bipolar output for legacy servo amplifiers without external DC/DC converters .
