Leakage current alarm indicator with Calibration Certificate MPU-1 WMPLMPU1

Network Safety and Continuous Leakage Current Monitoring

This device solves the problem of invisible leakage currents in low and medium voltage installations, ensuring continuous control over the electrical safety status. It operates as a stationary measurement system that not only records data but, above all, reacts immediately when a defined threshold is exceeded. This allows installers to quickly locate faults, while end-users can be certain that their infrastructure is protected against hazards resulting from leakage current flowing through the ground.

A key feature is the ability to set a custom alarm threshold. When the current value exceeds the specified limit (factory-set to 1 A), the device immediately activates an audible and visual alarm. The built-in speaker and LED indicators ensure the warning signal is clear even in noisy industrial environments or under poor lighting. This is not just a fault notification but a real tool for preventing fires or electric shocks.

Mounting Flexibility and Use in Difficult Conditions

The system is designed with various network configurations in mind. It utilizes flexible clamps (Rogowski coils) of the F series, which facilitates mounting on conductors with large cross-sections or in hard-to-reach places where rigid clamps would be useless. Importantly for installers working on overhead lines, the instrument allows simultaneous measurement using two independent clamps. Values from both sensors are summed, enabling effective monitoring of twin (twisted) poles without the need to expand the system with additional control units.

The device is compatible with AC networks operating at 50 Hz and 60 Hz, making it a universal tool in various geographical locations. Automatic measurement range selection simplifies operation – the user does not need to manually switch scales when the current value changes dynamically. The system also monitors the battery charge status, eliminating the risk of sudden shutdown during critical moments of operation.

Applications and Key Operational Benefits

Primary applications include continuous monitoring in main switchboards, transformer stations, and medium voltage transmission lines. Thanks to an IP67 enclosure protection rating, the device can operate in outdoor conditions, resistant to dust and heavy rain. Power is provided by a NiMH battery pack (9.4 V), which guarantees over 18 hours of standby time and over 3 hours of continuous operation in alarm mode – sufficient time to perform full diagnostics or respond to an emergency event.

It is worth noting the measurement precision confirmed by the calibration certificate included with the device:

• In the range 0.1 A ... 9.9 A, the resolution is 0.01 A (error ±(5% of reading + 2 digits)).
• In the range 10 A ... 299 A, the resolution is 1 A (error ±(5% of reading + 2 digits)).

The device features compact dimensions of 125 x 150 x 95 mm and a weight of approx. 1.1 kg with batteries, facilitating transport and mounting in limited switchboard spaces. The operating temperature range from -10°C to +50°C allows for operation in diverse climatic conditions. Thanks to its ergonomic design and intuitive operation, the MPU-1 minimizes the time required for installation and configuration. The device meets rigorous EMC standards (PN-EN 61326-1:2013 and PN-EN 61326-2-2:2013), guaranteeing stable operation even in environments with strong electromagnetic interference. It is a solution dedicated to scenarios where the safety of people and property depends on a rapid response to irregularities in leakage current flow.