Glossaire: Derating

Derating describes a necessary reduction of the maximum output power under specific operating conditions.

Derating may be necessary for example with:

• low input voltages
• high temperatures
• extremely low temperatures
• mounting positions which deviate from standard
• installation altitudes above 2000m

In many cases, a reduction of the maximum permitted ambient temperature or the use of forced ventilation (fan) offer a possible alternative to derating.

The user is responsible for observing the derating. The devices have no automatic derating control. Brief periods of exceeding the permitted power usually do not cause any problems; longer periods may trigger thermal shutdown.