Danfoss FC 102 Design Manual page 12

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mechanism. Restart is prevented until the cause of the
fault has disappeared and the trip state is cancelled by
activating reset or, in some cases, by being programmed
to reset automatically. Trip may not be used for personal
safety.
Trip Locked
A state entered in fault situations when the frequency
converter is protecting itself and requiring physical
intervention, e.g. if the frequency converter is subject to a
short circuit on the output. A locked trip can only be
cancelled by cutting off mains, removing the cause of the
fault, and reconnecting the frequency converter. Restart is
prevented until the trip state is cancelled by activating
reset or, in some cases, by being programmed to reset
automatically. Trip locked may not be used for personal
safety.
VT Characteristics
Variable torque characteristics used for pumps and fans.
plus
VVC
If compared with standard voltage/frequency ratio control,
Voltage Vector Control (VVC
and the stability, both when the speed reference is
changed and in relation to the load torque.
60 ° AVM
Switching pattern called 60° Asynchronous Vector
Modulation (See 14-00 Switching Pattern).
1.1.2 Power Factor
The power factor is the relation between I
3 × U × I 1 × COS ϕ
Power factor =
3 × U × IRMS
The power factor for 3-phase control:
I × cos ϕ1 I
1 1
= = since cos ϕ1 = 1
I I
RMS RMS
The power factor indicates to which extent the frequency
converter imposes a load on the mains supply.
The lower the power factor, the higher the I
same kW performance.
I 1 2 I 5 2 I 7 2
IRMS
= + +
In addition, a high power factor indicates that the different
harmonic currents are low.
The frequency converter's built-in DC coils produce a high
power factor, which minimises the imposed load on the
mains supply.
10
plus ) improves the dynamics
1
I n 2
+ . . +
Danfoss A/S © Rev. 06/2014 All rights reserved.
Design Guide
and I .
RMS
for the
RMS
MG11BC02