The AM5 Series Protection Relay from Acrel is a flexible and intelligent device designed to provide high-level electrical protection across a wide range of industrial and utility applications. It integrates directional overcurrent, earth fault, overload, thermal, voltage/frequency, and non-electrical fault detection into a single modular unit. With advanced relay logic including bus tie, auto-recloser, motor and transformer protection, and standby power switching, the AM5 ensures secure operation of low-voltage and medium-voltage equipment. Its rich communication capabilities and event logging functions make it ideal for SCADA, EMS, and substation automation.

Technical Specifications

Feature	Specification
Model	AM5 Series (variants include F, T, M, C, B, etc.)
Protection Functions	Overcurrent (2–3 stages), Earth fault (IDMT), Over/Undervoltage, Overload (trip/alarm), PT disconnection, Auto-reclose, Frequency, Directional Power, Thermal overload, Residual overvoltage, Unbalance, Negative sequence current, etc.
Control Functions	Bus tie, standby power switching, capacitor undervoltage, motor block
Alarm Types	Voltage loss, phase unbalance, incorrect phase sequence, rotor blocking, overfrequency/underfrequency
Measurement	Voltage, current, frequency, power (P, Q), power factor, energy
Event Logging	Trip context, sequence of events (SOE)
Communication Interfaces	RS485 (1 or 2 ports)
Protocols Supported	Modbus, IEC 60870-5-103, IEC 60870-5-101
Mounting Type	Panel mount
Display & Control	LCD-based with configuration keys
Power Supply Options	AC/DC 110V, 220V, 48V
Input Current Rating	1A or 5A (selectable), both current and neutral
Wiring	Customizable as per circuit type and model option
Anti-Pumping & GPS Sync	Optional

Functions

• Line, motor, transformer, and capacitor protection
• Multi-stage overcurrent and earth fault detection
• Directional protection with voltage dependence
• Frequency, voltage, power, and thermal overload supervision
• Remote trip/close circuit supervision
• Data acquisition, logging, and real-time fault diagnostics
• Communication with centralized systems via RS485 and IEC protocols
• Optional anti-pumping and GPS synchronization modules

Applications

• Industrial motor control and overload protection
• Transformer and feeder protection in substations
• Switchgear busbar and standby power automation
• Power factor correction capacitor bank protection
• Smart grid and energy automation solutions
• Metro, rail, and large facility electrical protection systems

Manufacturer Information

Acrel Co., Ltd., established in 2003, is a high-tech enterprise specializing in energy efficiency management and electrical safety solutions. With a comprehensive product line ranging from cloud platform software to sensors, Acrel offers smart energy meters, power sensors, and protection devices. Their products are widely utilized across industries such as electric power, communications, rail transit, petrochemical, and construction. In 2012, Acrel was listed on the Growth Enterprise Market with the stock code 300286.SZ. The company is committed to delivering innovative and reliable energy management solutions to its global clientele.