GOSSEN METRALINE MF (M520F) Installation Tester

Electrical contractors and maintenance technicians use the METRALINE MF for verifying safety of electrical installations in residential, commercial, and industrial buildings. It measures insulation resistance, loop impedance, line impedance, RCD trip time and current, voltage, frequency, continuity, and phase sequence.

Key specifications

• Insulation resistance test voltages: 50 V, 100 V, 250 V, 500 V, 1000 V
• Insulation resistance range: 0.01 MΩ to 1000 MΩ
• Loop impedance range: 0.01 Ω to 2000 Ω
• RCD test types: A, AC, F; test currents: 10 mA, 30 mA, 100 mA, 300 mA, 500 mA, 1000 mA
• Voltage measurement: 0–500 V AC/DC
• Continuity test current: >200 mA
• Safety rating: CAT III 600 V / CAT IV 300 V
• Display: large LCD with backlight
• Internal memory: up to 1000 measurements
• Interface: USB for PC connection
• Power supply: 6 × 1.5 V AA batteries
• Protection class: IP40
• Standards compliance: IEC 60364-6, EN 50110, VDE 0100-600
• Software: METRALINE MF PC software for data management and reporting
• Phase sequence test: yes
• Automatic test sequences: yes, for RCDs and insulation
• Earth resistance measurement: via optional adapter

Why choose it

The METRALINE MF combines all essential installation testing functions in one handheld device, with automatic test sequences to speed up verification. Its large backlit display and internal memory make it practical for daily use on site.

Ideal use cases

• Initial verification of new electrical installations
• Periodic testing of existing installations
• Troubleshooting RCD tripping issues
• Measuring insulation resistance of wiring and equipment
• Checking phase sequence in three-phase systems

Good to know

The METRALINE MF PC software allows you to transfer measurement data to a computer for reporting and documentation. Earth resistance measurement is possible with an optional adapter.