SPD Surge Protective Device T2 1P TNC network In=20kA Imax=40kA Up≤1.35kV SPE140

Protection of TNC installations against surges

The T2 surge protective device is designed to protect single-phase circuits in TN-C type networks. It protects the electrical installation from the effects of atmospheric surges (lightning discharges) and switching surges occurring during the switching on and off of loads. The device is suitable for switchboards in residential, commercial, and industrial buildings - anywhere where effective but economical protection against voltage impulses is required.

Operating parameters and energy absorption capacity

The device is characterized by a nominal discharge current In = 20 kA and a maximum discharge current Imax = 40 kA (8/20 µs waveform). This means it easily handles typical surges occurring in building installations - both those from distant lightning discharges and those generated by motors, transformers, or household appliances. The maximum continuous operating voltage Uc is 275 V AC, which provides an adequate safety margin for a nominal network voltage of 230/400 V. The protection level Up ≤ 1,35 kV guarantees that the voltage reaching the protected devices will remain below the damage threshold for sensitive electronics.

The short-circuit strength Isccr at a level of 50 kA allows for cooperation with fuse links up to 315 A in a shunt connection or up to 80 A in a V-configuration - providing great flexibility when selecting upstream overcurrent protection.

Construction and status signaling

The module occupies one module width on the TH35 rail (DIN rail), enabling compact installation even in switchboards with limited space. The maximum cross-section of the connected conductor is 50 mm² for single-core or multi-core rigid wire and 35 mm² for flexible multi-core cable - a large enough range to handle both thin load circuits and thicker main switchboard supplies.

An optical wear indicator provides information on the current state of the protection module without the need for disassembly or measurements. When the protective element exhausts its energy absorption capacity, a visible change signals the need for replacement. The enclosure protection rating IP2XC means dust-tightness and protection against access with fingers and tools.

The device meets the requirements of the Type 2 test class - it is the optimal choice for protecting end circuits behind a main Type I surge protector or as standalone protection in installations that do not require resistance to direct lightning strikes.