VLT
®
4000 VT
■
Derating for ambient temperature
The ambient temperature (T
AMB,MAX
) is the maximum
temperature allowed. The average (T
AMB,MAX
)
measured over 24 hours must be at least 5ºC lower.
If VLT 4000 VT is operated at temperatures above 45 ºC,
a derating of the continuous output current is necessary.
The current of VLT 4152-4652, 380-460 V and
VLT 4102-4402, 525-600 V, is to be derated
1%/ºC above 40ºC.
■
Derating for air pressure
Below 3300 feet altitude no derating is necessary.
Above 3300 feet the ambient temperature (T
AMB
)
or max. output current (I
VLT,MAX
) must be derated
in accordance with the diagram below:
1. Derating of output current versus altitude
at T
AMB
= max. 45°C
2. Derating of max. T
AMB
versus altitude at
100% output current.
MG.40.A7.22 - VLT is a registered Danfoss trademark
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