Product Description

Model Number Interpretation

• 2: Standard industrial accessory series

• SR: Snubber Resistor (braking/absorption unit)

• 5: 575 VAC (750 VDC) voltage class

• 1800: 1800 W continuous power rating

Technical Specifications

• Rated Power: 1800 W (continuous); 18,000 W (peak/instantaneous)

• AC Voltage Class: 575 VAC (±10%), 3‑phase, 50/60 Hz

• DC Bus Voltage: 750 VDC (max)

• Resistance: ~25 Ω (typical)

• Duty Cycle: 20–50% (depending on drive HP)

• Enclosure: NEMA 1 (indoor, ventilated steel)

• Cooling: Forced‑air fan (115/230 VAC)

• Dimensions (H×W×D): ~462 × 260 × 267 mm (18.2 × 10.25 × 10.5 in)

• Weight: ~18–20 kg (40–44 lbs)

• Certifications: UL 508, CE (legacy)

• Cross Part: D2‑3291 (Reliance internal)

Interface & Indicators

• Power Terminals: L/N (fan power); DC+ / DC− (drive DC bus)

• Status LEDs:

  • DC Bus Lamp: ON when >50 VDC present

  • Braking Active Lamp: ON during energy dissipation

• Fault Contact: Dry contact (S1‑2) for remote alarm signaling

Core Functions

• High‑Power Regeneration: Dissipates 1800 W continuous for heavy braking loads

• Overvoltage Protection: Clamps DC‑bus spikes to 750 VDC, preventing IGBT damage

• Fan‑Cooled Reliability: Sustains full power in high‑duty‑cycle applications

• LED Status & Remote Alarm: Local and remote monitoring of DC bus and braking activity

• Legacy 575 VAC Compatibility: Drop‑in replacement for Reliance GP‑2000/SP500 575 VAC systems

Application Scenarios

• Reliance GP‑2000/SP500 Drives: 575 VAC, 20–50 HP systems

• Heavy Industrial: Cranes, conveyors, mixers with frequent/rapid deceleration

• Legacy Automation: Replacement for failed 2SR51800 in 575 VAC drive panels

Usage & Maintenance

• Installation: Mount vertically; allow 150 mm clearance for airflow

• Wiring: Use 12 AWG (4 mm²) stranded copper; torque terminals to 1.5 N·m

• Power‑Up: Energize fan first, then connect DC bus; verify ≤750 VDC

• Maintenance: Quarterly—clean fan filter, check LEDs, tighten terminals

• Safety: Disconnect AC/DC; wait 10 minutes for capacitors to discharge