The DEHN DK 25 through-conductor terminal (manufacturer's part number 952699) is a specific component for installing surge protection devices in electrical installations. It connects comb rails and enables wiring via busbars, providing a flexible and secure connection option for surge diverter combinations. The device is designed for use in enclosures and is mounted on a 35-mm DIN rail in accordance with EN 60715, with an installation width corresponding to one module unit according to DIN 43880. The terminal is rated for use in electrical installations with nominal voltages up to 500 V AC/DC, and features a rated insulation voltage of 630 V and a rated impulse voltage withstand of 6 kV, ensuring safe insulation even under transient voltage stresses.

Applications
The DK 25 is primarily used in switchgear where surge protection devices are connected via comb rails. It enables the connection of multiple devices in a row, resulting in structured and clear wiring. The terminal is particularly suitable for installations requiring high reliability of electrical connections, such as industrial or commercial electrical systems. Mounting on DIN rails allows for standardized and quick installation in existing enclosures.

Functions and Features in Detail
The DK 25 through-conductor terminal is rated for a nominal current load of 100 A, ensuring safe current transmission even under higher loads. The maximum connection cross-section is 25 mm² for stranded cables and 16 mm² for fine-stranded cables, with a minimum cross-section of 1.5 mm². This range allows for connection of various cable types, both rigid and fine-stranded. The terminal is lightning current-tested and rated for surge currents up to 100 kA (10/350 µs), ensuring high robustness against transient current surges. This is particularly important in installations containing surge protection devices, as these can conduct high current impulses during discharges.

Technology Explained Simply
The DK 25 functions as an electrical transition point, enabling cables to be connected via a comb rail without requiring a direct connection between two cables. This reduces the number of required connections and improves circuit clarity. The terminal is made of a thermoplastic material with UL 94 V-0 flame resistance rating, ensuring high safety at elevated temperatures or in case of fire. The IP20 protection rating means the device is protected against contact with fingers and against solid objects larger than 12.5 mm, but not against water or dust. The operating temperature range is between −40 °C and +80 °C, allowing use in a wide range of environments, including industrial installations with extreme temperatures.

Compatibility and Accessories
The DK 25 is specifically designed for use with surge protection devices mounted on comb rails. It is compatible with surge diverter combinations connected via busbars and enables structured wiring. The terminal is mounted on a 35-mm DIN rail, ensuring standardized installation in enclosures. No specific accessories are mentioned in the sources; however, combining it with other Dehn surge protection devices mounted on comb rails is typical.

Installation and Mounting
Mounting is performed on a 35-mm DIN rail in accordance with EN 60715, with an installation width equal to one module unit according to DIN 43880. The terminal is secured using a screw mechanism that ensures a reliable connection. Installation does not require special tools, but careful securing of the cables is necessary to ensure a stable electrical connection. The terminal is designed for mounting in enclosures, and the IP20 protection rating requires indoor use.

Operational Advantages
The DK 25 provides a reliable and structured connection option for surge protection devices. The high surge current withstand capability of 100 kA (10/350 µs) ensures safe operation even under high transient current surges. The use of thermoplastic material with UL 94 V-0 flame resistance rating increases operational safety. Mounting on DIN rails enables quick and standardized installation, simplifying maintenance and expansion of the installation. The terminal supports a wide range of cable cross-sections, offering flexibility in wiring planning.