Operating Temperature of Cables and Derating SWGR

The switchgear item may require that wiring be selected at say the 60°C or 75° rating. This ensures that a hotter-running wire does not conduct too much heat into the switching device.

For example, a 90°C rated wire, if loaded at full rating, could overheat a CB and lead to nuisance tripping.

Can you quote some evidence from a manufacturer or BS/IEC/NEC etc regarding application of a derating factor?

This information is sometimes printed directly on CBs or other switchgear, or is included in the data sheets or instructions.

I'm not sure the term "derating factor" is correct in this instance. This is not a multiplier; it is just a simple statement that wiring that could be hotter than a given value should not be used when connected to temperature-sensitive devices.

Thanks.Can some one send a copy to the forum which would be of use to many readers?

Hi guys,

I need a cable (it's for linear motors) which operating temperature is up to 150 Degrees (Celsia) . But with good mechanical features, according to cables quality 800Plus - minimum bending radius 75 mm,minimum static radius 45 mm, bending 10.000 000, max acceleration 5 m/s2, max.pulling force static 50 N /mm2, max. working voltage 30 Vrms . Halogenfree, with flame retardancy, PVC free, RoHS compliant, silicon free, FCKW free. Does anyone know if sth like this coud be found?