ALSTOM LC105A-1 Motor protection relay

ALSTOM LC105A-1 Technical Overview

1. General Description

The LC105A-1 is a low-voltage circuit breaker or motor protection relay designed for industrial and commercial electrical systems. It provides protection against overloads, short circuits, and phase faults in circuits powering motors, distribution panels, or critical loads. The “LC” designation often indicates a Line Circuit component, while “105” may denote a 105A current rating or product series.

2. Key Technical Specifications

• Electrical Ratings
  • Rated Voltage: 400–690V AC (typical for IEC markets).
  • Rated Current: Adjustable range up to 105A (specific trip settings vary).
  • Breaking Capacity: 10–36 kA (depends on model; compliant with IEC 60947-2).
  • Frequency: 50/60 Hz.
• Protection Functions
  • Overload Protection: Adjustable thermal-magnetic tripping (Ir, Tr).
  • Short-Circuit Protection: Instantaneous electromagnetic trip (Ii).
  • Phase Unbalance/Loss: Optional detection (requires additional modules).
  • Earth Fault Protection: Optional (if equipped with a ground-fault module).
• Mechanical Design
  • Poles: 3-pole or 4-pole (3P+N) configuration.
  • Mounting: DIN rail or fixed panel mounting.
  • Operating Mechanism: Rotary handle or motorized operation (optional).
• Environmental Ratings
  • Operating Temperature: -25°C to +60°C (-13°F to +140°F).
  • Ingress Protection: IP20 (indoor use) or higher with enclosures.
• Compliance Standards
  • IEC 60947-2 (circuit breakers), UL 489 (if UL-listed), CE Mark.

3. Functional Capabilities

1. Circuit Protection
   • Safely interrupts fault currents (short circuits or overloads) to protect downstream equipment like motors, transformers, and cables.
   • Adjustable trip thresholds to match load requirements.
2. Motor Protection (If Applicable)
   • Integrates thermal overload protection (mimicking motor heating curves) and phase-loss prevention.
3. Modularity
   • Supports add-on modules for auxiliary contacts, shunt releases, or communication (e.g., Modbus RTU).
4. Diagnostics
   • Status indicators (mechanical flags or LED lights) for trip cause identification (overload vs. short circuit).
5. Remote Control
   • Optional motorized operation or integration with SCADA systems via communication interfaces.

4. Applications

• Industrial Motor Control: Protection of pumps, fans, compressors, and conveyor systems.
• Power Distribution: Main or branch circuit protection in switchgear, MCCs (Motor Control Centers), or distribution boards.
• Renewable Energy Systems: Inverters, solar/wind farm collection networks.
• Commercial Buildings: HVAC systems, lighting panels, and data centers.

5. Ordering Information

• Model: LC105A-1 (suffixes may indicate voltage, trip settings, or accessories).
• Accessories: 
  • Auxiliary contacts (e.g., LC105A-1C for signaling).
  • Undervoltage release (UV), shunt release (SH).
  • Communication module (e.g., LC105A-COM for network integration).

Key Advantages

• Compact Design: Space-efficient for dense panel layouts.
• Selective Coordination: Ensures only the faulted circuit trips, minimizing downtime.
• Durability: High mechanical endurance (10,000+ operations).