9.2 Special
Conditions
9.2.1 Purpose of Derating
Derating must be taken into account when using the frequency converter at low air pressure (heights), at low speeds, with
long motor cables, cables with a large cross section or at high ambient temperature. The required action is described in this
section.
9.2.2 Derating for Ambient Temperature
The average temperature (T
AMB, AVG
) measured over 24 hours must be at least 5 °C lower than the maximum allowed
ambient temperature (T
AMB,MAX
).
If the frequency converter is operated at high ambient temperatures, the continuous output current should be decreased.
The derating depends on the switching pattern, which can be set to 60 AVM or SFAVM in parameter 14-00.
A enclosures
60 AVM - Pulse Width Modulation
Illustration 9.1 Derating of I
out
for different T
AMB, MAX
for
enclosure A, using 60 AVM
SFAVM - Stator Frequency Asyncron Vector Modulation
Illustration 9.2 Derating of I
out
for different T
AMB, MAX
for
enclosure A, using SFAVM
In enclosure A, the length of the motor cable has a relatively high impact on the recommended derating. Therefore, the
recommended derating for an application with max. 10 m motor cable is also shown.
Illustration 9.3 Derating of I
out
for different T
AMB, MAX
for
enclosure A, using 60 AVM and maximum 10 m motor cable
Illustration 9.4 Derating of I
out
for different T
AMB, MAX
for
enclosure A, using SFAVM and maximum 10 m motor cable
Specifications
ADAP-KOOL
®
Drive Operating Instructions
124
MG.11.L4.02 - ADAP-KOOL
®
Drive
9
9
