Danfoss FCM305 56, Инструкция по эксплуатации

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FCM 300 Series
MG.03.B6.2G - VLT is a registered Danfoss trademark
Special conditions
■
Derating
The FCM 300 Series is thermally protected. At high
temperatures the switching frequency will be
automatically reduced down to 2 kHz. If the
temperature still climbs, the motor will trip.
■
Derating for Air Pressure
Below (3300 ft.) altitude no derating is necessary.
Above (3300 ft.) the ambient temperature (T
AMB
) or
max. output current (I
VLT,MAX
) must be derated in
accordance with the following diagram:
1) Derating of output current versus altitude at
T
AMB
= max. 40°C /104 o F
2) Derating of max. T
AMB
versus altitude at 100%
output current.
18-2
Derating for ambient temperature
The ambient temperature (T
AMB,MAX
) is the maximum
temperature allowed. The average (T
AMB,AVG
)
measured over 24 hours must be at least 5ºC
lower.
If FCM 300 Series is operated at temperatures
above 40 ºC, a derating of the continuous output
current is necessary.
Derating for running at low speed
When a centrifugal pump or a fan is controlled by
a FC motor, it is not necessary to reduce the
output at low speed because the load
characterstic of the centrifugal pumps/fans,
automatically ensures the necessary reduction.
FC motors running constant load torque
applications continuously at low speed must be
derated (see diagram) or an independent fan must
be used (cooling option 6).
Nominal torque (100%) can be yielded up to
15 min and at a duty cycle up to 25% at low
speed.
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