# 25ka Surge Arrester 25GR 4P Type 1 Technical Specifications and Features

## Introduction to the 25ka Surge Arrester 25GR 4P Type 1

The 25ka Surge Arrester 25GR 4P Type 1 is a high-performance protective device designed to safeguard electrical systems from transient overvoltages caused by lightning strikes or switching surges. This industrial-grade surge protection device (SPD) offers reliable protection for three-phase power distribution systems.

## Key Technical Specifications

### Electrical Characteristics

– Nominal Discharge Current (In): 25kA (8/20μs)
– Maximum Discharge Current (Imax): 50kA (8/20μs)
– Voltage Protection Level (Up): ≤2.5kV
– Nominal Voltage (Un): 400V AC
– Frequency Range: 50/60Hz

### Mechanical Specifications

– Number of Poles: 4 (3 phases + neutral)
– Connection Type: Screw terminals
– Housing Material: Thermoplastic (UL94 V-0)
– Protection Degree: IP20
– Mounting: DIN rail (35mm)

## Main Features and Benefits

### Advanced Protection Technology

The 25GR 4P Type 1 arrester utilizes high-quality metal oxide varistors (MOVs) with excellent energy absorption capabilities. The device features:

– Fast response time (<25ns)
– Low follow current
– High energy absorption capacity
– Thermal disconnector for safe failure mode

### Monitoring and Indication

– Visual status indication (green/red)
– Remote signaling contact (optional)
– Replaceable modules for easy maintenance

## Applications

This Type 1 surge arrester is specifically designed for:

– Main distribution boards
– Service entrance panels
– Industrial power systems
– Commercial buildings
– Critical infrastructure protection

## Compliance and Standards

The 25ka Surge Arrester 25GR 4P Type 1 complies with:

– IEC 61643-11
– EN 61643-11
– UL 1449 4th Edition
– CE Marking

## Installation Considerations

For optimal performance:

– Install at the service entrance point
– Ensure proper grounding (≤10Ω recommended)
– Follow manufacturer’s torque specifications for connections
– Maintain appropriate clearance distances
– Consider coordination with downstream Type 2 SPDs

## Maintenance and Service Life

The device features:

– Long operational life expectancy
– Easy module replacement without system shutdown
– Recommended annual visual inspection
– Performance monitoring through status indicator

The 25ka Surge Arrester 25GR 4P Type 1 provides robust protection against lightning-induced surges, ensuring system reliability and minimizing downtime in critical electrical installations.