1. General Information

• Part Number: 518317, 0-51831-7, CVTH

• Manufacturer: Reliance Electric (Rockwell Automation / ABB / Baldor)

• Series: CardPAK Engineered DC Drives (FlexPak / MinPak / MaxPak compatible)

• Type: CVTH – Current-Voltage Transductor Card (high‑accuracy isolation & sensing)

• Function: Isolated current/voltage sensing, precision signal conversion, field/armature current monitoring for DC drive regulation

• Status: Obsolete; refurbished / NOS available

• Mounting: Standard 3U Eurocard for CardPAK rack

• Cross‑reference: 518314 (CVTE, standard), 518315 (CVTU, timing), 518316 (CVTG, extended gain)

2. Electrical Specifications

• Backplane Supply: ±15 VDC (nominal)

• Power Consumption: ≤ 7 W

• Sensing Inputs:

  • Armature Current: 0–500 mV (shunt input, isolated)

  • Field Current: 0–500 mV (shunt input, isolated)

  • Armature Voltage: 0–600 VDC (scaled, isolated)

• Output Signals:

  • Isolated Current: 0–10 VDC (linear, 0–100% motor current)

  • Isolated Voltage: 0–10 VDC (linear, 0–100% armature voltage)

• Isolation Voltage: 1500 VAC (input‑to‑output, reinforced)

• Linearity: ±0.05% of full scale

• Temperature Coefficient: ±25 ppm/°C

• Adjustments: Onboard trimpots for Gain, Offset, Range Calibration

• Indicators: Power LED, Isolation Fault LED, Signal OK LED

• I/O Interface: Edge connector (backplane); front 4‑position screw terminal header (arm current, shunt, field shunt)

3. Mechanical Specifications

• Form Factor: 3U Eurocard

• Dimensions (W×H×D): 100 mm × 160 mm × 35 mm (approx, with heatsink)

• Weight: ~0.55 kg (~1.2 lb)

• Construction: Conformal coated PCB, industrial grade, brass heatsink, metal front panel

• Connector: Gold‑finger edge (backplane); front 4‑pin screw terminal header

4. Environmental Ratings

• Operating Temperature: 0 °C to +55 °C

• Storage Temperature: −20 °C to +70 °C

• Humidity: 10%–90% RH, non‑condensing

• Vibration: 10–100 Hz, 0.1 mm amplitude (operational)

• Certifications: UL, CSA, CE

5. Key Features

• High‑isolation current/voltage sensing for DC drive armature/field circuits

• Precision 0–10 VDC isolated outputs for closed‑loop control

• Wide input range: 0–600 VDC voltage, 0–500 mV shunt current

• Onboard trimpots for accurate field calibration (Gain/Offset/Range)

• Compact 3U Eurocard, fits standard CardPAK racks, hot‑swap capable

• Industrial robustness: conformal coating, brass heatsink, wide temp range

6. Compatibility

• Racks: CardPAK 6‑slot, 12‑slot, 18‑slot

• Drives: Reliance FlexPak, MinPak, MaxPak DC drive systems

• Interchangeability: 0-51831-7 / 518317 fully interchangeable