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GE 148D1645P2
Product Name: GE Multilin 148 Series Multifunction Digital Motor Protection Relay
Product Introduction: The GE 148D1645P2 is a digital multifunction protection relay in the GE Multilin 148 series, designed for comprehensive protection of medium- and low-voltage motors. The “148” denotes the 148 series of multifunction relays, “D” indicates digital design, “1645” represents the functional configuration code (overcurrent, ground fault, overload, imbalance etc.), and “P2” identifies firmware version 2.
Detailed content
Technical Specifications:
- Rated current: 5 A / 1 A (configurable)
- Rated voltage: below 600 V AC
- Measurement accuracy: ±0.5%
- Overcurrent protection (50/51): 0.5–30 A (adjustable)
- Ground fault protection (50G/51G): 0.5–30 A (adjustable)
- Overload protection (49): 0.4–12 × rated current (adjustable)
- Locked rotor protection (66): adjustable, 0–30 s delay
- Phase imbalance protection (46): 2%–50% (adjustable)
- Undervoltage protection (27): 20%–90% of rated voltage (adjustable)
- Overvoltage protection (59): 105%–130% of rated voltage (adjustable)
- Frequency protection (81): 45–65 Hz (adjustable)
- Communication interface: RS-485 (Modbus RTU)
- Auxiliary power: 110 V / 220 V AC or DC
- Operating temperature: -20 °C to +55 °C
- Protection rating: IP54 (front panel)
- Certifications: UL, CSA, CE, TÜV
Functional Features:
- Three-phase overcurrent protection (50/51) with inverse-time / definite-time characteristics
- Ground fault protection (50G/51G) with high sensitivity
- Motor overload thermal protection (49) with built-in thermal model
- Locked rotor protection (66) preventing motor burnout
- Phase sequence and phase imbalance protection (46)
- Undervoltage / overvoltage protection (27/59)
- Low frequency protection (81)
- Event recording and fault waveform capture (up to 64 events)
- LED panel display with field-adjustable parameters
Material Composition:
- Housing: flame-retardant ABS engineering plastic (UL94 V-0)
- Front panel: polycarbonate (PC) transparent cover
- Terminal blocks: copper alloy with nickel plating
- Internal PCB: FR-4 glass fiber board with conformal coating
Structural Features:
- 88 mm panel cutout (standard size)
- Front panel with 4-digit LED display and 4 push buttons
- Rear terminals including RS-485 communication terminals
- DIN 35 mm rail mounting
Application Scenarios: Industrial motor protection, water pumps, fans, compressors, conveyors, generator protection.
Working Principle: The relay receives current signals from the CT secondary side, compares them with set thresholds, and trips the output when any protection condition (overcurrent, ground fault, overload, locked rotor, phase imbalance, under/overvoltage, abnormal frequency) is reached. Parameter values and protection logic are configured via the front panel or Multilin software through RS-485.
Installation Requirements:
- 88 mm × 88 mm panel cutout, installation depth ≤ 80 mm
- Connect CT secondary side to relay current terminals (S1/S2)
- Connect control power to auxiliary power terminals
- Use shielded cable for RS-485 communication, with 120 Ω terminating resistor
Usage Notes:
- CT ratio must match the relay rated current setting
- Alarm output relay capacity is 3 A / 250 V AC — cannot directly drive heavy loads
- Firmware upgrade requires Multilin software via RS-485
- Regularly verify protection settings against actual motor parameters
