Special Conditions - Danfoss VLT AQUA Drive Operating Instructions Manual

10. Specifications

10.2. Special Conditions

10.2.1. 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.
10.2.2. Derating for Ambient Temperature
The average temperature (T
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 10.1: Derating of I
10
using 60 AVM
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 10.3: Derating of I
using 60 AVM and maximum 10 m motor cable
150
) measured over 24 hours must be at least 5 °C lower than the maximum allowed ambient temperature (T
AMB, AVG
for different T for enclosure A,
out AMB, MAX
for different T for enclosure A,
out AMB, MAX
MG.20.M4.02 - VLT
SFAVM - Stator Frequency Asyncron Vector Modulation
Illustration 10.2: Derating of I
using SFAVM
Illustration 10.4: Derating of I
using SFAVM and maximum 10 m motor cable
®
is a registered Danfoss trademark
®
VLT AQUA Drive
Operating Instructions
AMB,MAX
for different T for enclosure A,
out AMB, MAX
for different T for enclosure A,
out AMB, MAX
).