A specification showing how a rating stated at a particular temperature is reduced at higher temperatures. NOTE 1 Derating is usually expressed graphically or in terms of derating factors (e.g., mA/°C or mW/°C). Peak pulse power ratings may exceed zero at the maximum-rated junction temperature. ...

What is meant by derating factor?

The derating factor is applied to reduce the cable's current carrying capacity. For example, if a X-90 cable can carry 40A @90 degrees, there may be additional factors which requires the cable to be de-rated such that it carries only 30A@90 degrees in the installation.

What is the purpose of derating factor?

The photovoltaic (PV) derating factor is a scaling factor that HOMER applies to the PV array power output to account for reduced output in real-world operating conditions compared to the conditions under which the PV panel was rated.