OVR T2 varistor-based surge protective devices limit dangerous transient overvoltages to a level that is compatible with the equipment. The switching of circuit breakers, transformers, motors, and inductive loads in general, or the sudden change of loads, causes sudden current fluctuations (di/dt) that generate transient overvoltages.
While they are not as energetic as overvoltages caused by lightning, they occur much more frequently and can cause damage because they are generated directly in the power supply network of the electrical installation. Their short duration, steep rising edge, and peak value (which can reach several kV) lead to premature wear of electronic devices.
Type 2 tested surge protective devices are usually used as the second protection stage in sub-distribution boards or in final circuits to protect equipment against overvoltages. T2 SPDs are characterized by their capacity to safely discharge current with an 8/20 µs waveform. They are tested in accordance with the test standard IEC 61643-11.
The OVR Type 2 surge arresters are available in specific multi-pole versions for all mains systems. Depending on the version, the maximum protection level is Up to 1.5 kV, making them suitable for protecting connected sensitive equipment. The protective devices can be used for the following system voltages: Uc 275 V, 350 V, and 440 V. Varistors with Imax ratings of 15 kA, 40 kA, and 70 kA are available.
Main benefits
- OVR T2 SPDs are available in specific multi-pole versions for all distribution systems
- For all versions the maximum protection level Up is 1.25 kV, a value suitable for the protection of all terminal equipment
- Safety reserve system on OVR T2s for an extended protection of the equipment
Main features
- Imax 40kA and 80kA
- Up 1.4kV and 1.5kV
- Uc (a.c/d.c) 150V, 275V, 350V, 440V
- IEC: TT, TNS, TNC & IT system covered
- UL: Delta, Wye, Split phase, Single phase distribution network
- IEC and UL approved version (OVR T2 U series)