Sigma resistors comply of one or multiple ceramic wirewound resistors fitted with a protection grid and optional connection box and or thermal switch. The ingress protection can be IP00 or IP21. Nominal power ranges from 180W till 5kW.
On request a UL approved version is available.
* power rating with natural air cooling
Ceramic Wirewound resistors are build up from a ceramic core where a resistor wire in wound on. The are offered in various diameters ranging from 10 till 55mm and lengths from 44 till 590mm. The resistor has either a round or flat oval shape. Coating can be cement or vitreous enameled. These kind of traditional resistors are well proven and very cost effective. Applications are charging and de-charging resistors, brake resistors for small drives systems, snubbers in controlled and uncontrolled rectifiers.