Residual current device PR 304 4P 63 A 30 mA type AC, DX3 series 410500

Residual Current Device – Protection and Installation Safety

This four-pole residual current device PR 304 from the DX3 series is a critical component ensuring safety in every electrical installation. Designed to protect against electric shock and the consequences of earth faults, it provides a reliable protective barrier for people and equipment. Its applications are wide-ranging—from residential installations, through commercial facilities, to industrial buildings.

Functionality and Specifications

The device features a rated current of 63 A and a sensitivity of 30 mA AC residual current. This ensures effective response to earth leakage currents, minimizing the risk of electric shock. The locking mechanism prevents accidental re-energizing after tripping, further enhancing safety. The rated voltage range of 250–440 V AC enables universal use across various electrical networks. Note that the residual current cannot be adjusted—this model provides a fixed 30 mA value, ensuring precise protection.

The use of AC characteristic makes the device particularly effective in detecting alternating leakage currents, which are the most common cause of electric shocks. The IP20 protection rating guards against finger contact but does not protect against water or dust; therefore, the device must be installed in dry, enclosed environments. The ability to connect conductors with cross-sections from 1.5 mm² to 35 mm² (single-core) or from 1.5 mm² to 25 mm² (multi-core) offers great flexibility during installation.

In addition, the device has a rated impulse withstand voltage (Uimp) of 4 kV, guaranteeing resistance to voltage surges and ensuring long-term reliability even under demanding operating conditions. The operating ambient temperature range is from -25°C to 70°C, allowing use in various climates and environments.