Surge protection is a device that protects against transient overvoltages by limiting the frequency and duration of the subsequent current. These devices are also known as lightning arresters, surge protectors or varistors. Surge arresters protect equipment connected to the mains and are also an essential part of the protection of solar installations.

T1/T2 (B + C) surge protectors are designed to discharge high surge currents with a waveform of 10/350 μs that occur as a result of lightning strikes in three-phase and single-phase power supply networks (overhead lines) and/or overvoltages due to switching in the circuit (with a waveform of 8/20 μs). They are manufactured as compact units. Surge protection devices including protection units type 1 and 2 (T1/T2) are to be installed after the first short-circuit protection device, directly behind the electricity meter (in the main electricity distribution board).

Application to protect the electrical equipment of a photovoltaic system from the effects of overvoltages
operation indicator green – protection

red – no protection

Protection class T1 T2
Modules 4
Requirements T1 T2
max. operating voltage Uc 320 V AC
Test for current (8/20) In 20 kA
max. current (8/20) Imax 50 kA
Voltage protection level Up ≤ 1,8 kV
Expected current Iimp 7 kV
Protection 32 A
Line max. 35mm2
Execution varistor
Degree of protection IP20
Storage temperature from -30oC to +70oC
Operating temperature range from -30o to +50oC
Mounting DIN (TH/TS 35)
Standards CE, IEC61643-11
Brand Doktorvolt
Catalogue number DV-5064

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