FC standard bus
Includes RS485 bus with FC protocol or MC protocol. See
parameter 8-30 Protocol.
THD
Total harmonic distortion states the total contribution of
harmonic.
Thermistor
A temperature-dependent resistor placed on the frequency
converter or the motor.
Trip
A state entered in fault situations, for example if the
frequency converter is subject to an overtemperature or
when the frequency converter is protecting the motor,
process, or mechanism. The frequency converter prevents a
restart until the cause of the fault has disappeared. To
cancel the trip state, restart the frequency converter . Do
not use the trip state for personal safety.
Trip lock
The frequency converter enters this state in fault situations
to protect itself. The frequency converter requires physical
intervention, for example when there is a short circuit on
the output. A trip lock can only be cancelled by discon-
necting 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.
Do not use the trip lock state for personal safety.
VT characteristics
Variable torque characteristics used for pumps and fans.
VVC
+
If compared with standard voltage/frequency ratio control,
voltage vector control (VVC
+
) improves the dynamics and
the stability, both when the speed reference is changed
and in relation to the load torque.
60° AVM
60° asynchronous vector modulation
(parameter 14-00 Switching Pattern).
Power factor
The power factor is the relation between I
1
and I
RMS
.
Power factor = 
3xUxI
1
cosϕ
3xUxI
RMS
The power factor for 3-phase control:
= 
I1xcosϕ1
I
RMS
 = 
I
1
I
RMS
sincecosϕ1 = 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.

I
RMS
= 
I
1
2
 + I
5
2
 + I
7
2
 + .. + I
n
2
In addition, a high-power factor indicates that the diî‚„erent
harmonic currents are low.
The DC coils in the frequency converters produce a high-
power factor, which minimises the imposed load on the
mains supply.
1.7
Abbreviations, Symbols and
Conventions
°C
Degrees celsius
AC Alternating current
AEO Automatic energy optimisation
AWG American wire gauge
AMA Automatic motor adaptation
DC Direct current
EMC Electro magnetic compatibility
ETR Electronic thermal relay
f
M,N
Nominal motor frequency
FC Frequency converter
I
INV
Rated inverter output current
I
LIM
Current limit
I
M,N
Nominal motor current
I
VLT,MAX
Maximum output current
I
VLT,N
Rated output current supplied by the
frequency converter
IP Ingress protection
LCP Local control panel
MCT Motion control tool
n
s
Synchronous motor speed
P
M,N
Nominal motor power
PELV Protective extra low voltage
PCB Printed circuit board
PM Motor Permanent magnet motor
PWM Pulse width modulation
RPM Revolutions per minute
Regen Regenerative terminals
T
LIM
Torque limit
U
M,N
Nominal motor voltage
1.8 Safety
WARNING
HIGH VOLTAGE
Frequency converters contain high voltage when
connected to AC mains input, DC supply, or load sharing.
Failure to perform installation, start-up, and maintenance
by qualied personnel can result in death or serious
injury.
•
Only qualied personnel must perform instal-
lation, start-up, and maintenance.
Safety regulations
•
Disconnect mains supply to the frequency
converter whenever repair work is to be carried
out. Check that the mains supply has been
disconnected and that the necessary time has
elapsed before removing motor and mains supply
Introduction Programming Guide
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