Hybrid surge arrester DEHNventil ZP TNC "DV ZP TNC 255" 900390

Surge Protection in TN-C Networks – No Compromises

This device is designed for mounting at the bottom of the metering board, directly onto a 40 mm pitch busbar – without the need for tools. Installation is quick, and its location complies with VDE-AR-N 4100 requirements for applications upstream of the metering system. It is a key protection element in buildings with an external lightning protection system, where the risk of a direct lightning strike is real.

Operates as Type 1+2 – One Device, Two Functions

The combination of Type 1 and Type 2 in a single enclosure means the device handles both the highest surge currents (e.g., from a lightning strike on the external installation) and smaller, but more frequent, surges inside the building. The spark gap technology with RADAX-Flow function enables effective extinguishing of follow current – eliminating the risk of arc persistence after activation. This not only protects the installation but also prevents fuse failures and power interruptions.

Surge Current 75 kA and Protection Voltage ≤1.5 kV – For Real-World Conditions

In TN-C networks, where the PEN conductor serves as both neutral and protective, this surge arrester handles a maximum surge current of 75 kA (10/350 µs) across all three phases together with PEN. The protection voltage does not exceed 1.5 kV – meaning surge energy is effectively limited before reaching end devices. It coordinates energetically with other surge arresters from the Red/Line series and directly with loads – eliminating the need for additional system coordination.

Follow Current Extinguishing Capability: 25 kA – Safe for the Installation

Some surge arresters may cause a short circuit after activation. This one does not – its follow current extinguishing capability is 25 kA rms. This means it can be used in circuits protected by gG fuses up to 315 A without risk of line damage or device explosion. No additional backup protection is required – its design inherently ensures selectivity.

Visual Indicator – Status Visible Without Tools

There are no signal wires or contacts here. Instead, a simple yet effective visual indicator on the enclosure shows the operational status: it lights up during normal operation and goes out when the component is exhausted. The installer can quickly assess the device's condition during inspection – without disconnection or measurement.

For TN-C Networks – And Only TN-C

This device operates exclusively in TN-C systems. There is no point in installing it in TN-S or TT systems – it does not match their wiring scheme (3-pole, L1+L2+L3+PEN). Its design and VDE certification are tailored specifically to this network type – where PEN is common from the transformer up to the distribution point. For other systems, select model DV ZP TT 255 (4-pole).

IP30 – For Indoor Panel Use Only

This is not a water-resistant device. Its IP30 rating provides protection only against solid objects larger than 2.5 mm – sufficient for the interior of metering or distribution boards. Do not install it outdoors or in damp locations.