Residual current device PR 304 4P 40 A 30 mA Type A DX3 series 410525

Safety and Protection in Your Electrical Installation

The residual current device (RCD) PR 304 4P 40A 30mA Type A from the DX3 series is a critical component ensuring safety in every electrical circuit. This device effectively protects against electric shock and safeguards the installation against the consequences of earth faults, minimizing fire risk. This is especially important in high-humidity areas such as bathrooms and kitchens, as well as in workplaces and public buildings.

Functionality and Application

The RCD PR 304 is designed to protect circuits with a rated current of 40A. Its sensitivity to leakage current of 30mA ensures rapid disconnection in case of insulation failure, cutting off power and preventing danger to users. The 4-pole design allows full circuit protection, including the neutral conductor. Type A indicates that the device is capable of detecting both alternating leakage currents and those with a DC component or pulsed characteristics—essential for protecting modern electronic equipment. Installation is performed on a DIN rail, simplifying integration into existing electrical systems.

Key Features and Benefits

• High reliability: Constructed from high-quality materials, ensuring long-term, fault-free operation.
• Fast response: 30mA sensitivity guarantees immediate circuit disconnection upon leakage detection.
• Versatile application: Suitable for protecting various circuits—from sockets to lighting.
• Easy installation: DIN rail mounting simplifies and accelerates installation.
• Mechanical lock: Prevents accidental re-energizing after tripping—enhancing safety during maintenance.
• Wide operating temperature range: Operates reliably from -25°C to 70°C, making it suitable for diverse environmental conditions.
• Compatible with various conductor sizes: Supports single-core cables from 1.5 mm² to 35 mm² and multi-core cables from 1.5 mm² to 25 mm².

Technical Parameters in Practice

The PR 304 RCD features a rated voltage range of 250V to 440V and an insulation voltage (Ui) of 500V, ensuring compatibility with most electrical installations. Its impulse withstand voltage (Uimp) reaches up to 4kV, demonstrating high resistance to voltage surges. The leakage current cannot be adjusted, meaning the device is ready for immediate operation after installation—no additional settings required. The IP20 protection rating provides defense against finger contact and solid objects larger than 12.5mm—sufficient for most indoor applications. With a width of 4 modules, the device enables efficient space utilization in distribution boards.