What derating factors are applied to contactors at altitude?

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What derating factors are applied to Tesys K, D, G contactors at altitude?

For contactors in the TeSys ranges (K, D & G) Please apply the following:

No derating below 3000m altitude for voltage and current in the power poles of the contactors.

Derating table for Tesys D contactors

For example, a LC1D80 at 5000m :

The maximum rated operational voltage is 1000V (IEC 947-4) and 690V (UL/CSA). At 5000m it becomes 1000V x 0.6 = 600V (IEC 947-4) and 690V x 0.6 = 414V (UL/CSA).
The maximum rated operational AC3 current is 80A at 5000m becomes 80A x 0.86 = 68A.