Varistors with higher operating temperature for overvoltage protection

August 08, 2017 //By Nick Flaherty
TDK has launched leaded metal oxide disk varistors that have been approved for an increased operating temperature of 105 °C, up from 85 °C.

The recertification of the EPCOS B722 series of varistors is in accordance with UL 1449, 4th Edition, and IEC 61051. Raising the permissible operating temperature to 105 °C also changes the climate category from 40/85/56 to 40/105/56. The flammability of the epoxy enclosure complies with UL 94 V-0.

The monolithic EPCOS varistors are available with rated voltages of between 11 VRMS and 1100 VRMS and, depending on type, can withstand surge currents of up to 20 kA (8/20 µs). To assist in the design process, PSpice libraries are available at www.epcos.com/tools_mlv.

The varistors are aimed at the protection of power supply and converter inputs for industrial electronics applications, as well as household appliances and telecommunication devices.

Further information is at www.epcos.com/varistors_leaded