GE AF-600 FP Series, Design Manual

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Trip
A state entered in fault situations, e.g. if the frequency converter is subject to an over-temperature or when the frequency converter is protecting the motor,
process or 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.
60° AVM
Switching pattern called 60°Asynchronous Vector Modulation (See par. F-37
Adv. Switching Pattern ).
1.1.7 Power Factor
The power factor is the relation between I
1
and I
RMS
.
Power factor
=
3 × U × I
1 ×
COS
ϕ
3 × U × IRMS
The power factor for 3-phase control:
=
I
1 ×
cos
ϕ 1
IRMS
=
I
1
IRMS
since cos
ϕ 1 = 1
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
RMS
for the same kW performance.
IRMS
=
I
1
2 +
I
5
2 +
I
7
2 + . . +
In
2
In addition, a high power factor indicates that the different harmonic currents are low.
The frequency converters' built-in DC coils produce a high power factor, which minimizes the imposed load on the mains supply.
AF-600 FP Design Guide
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