ETR
Electronic thermal relay is a thermal load calculation based
on present load and time. Its purpose is to estimate the
motor temperature.
FC standard bus
Includes RS485 bus with FC protocol or MC protocol. See
parameter 8-30 Protocol
.
Initializing
If initializing is carried out (
parameter 14-22 Operation
Mode
), the frequency converter returns to the default
setting.
Intermittent duty cycle
An intermittent duty rating refers to a sequence of duty
cycles. Each cycle consists of an on-load and an off-load
period. The operation can be either periodic duty or non-
periodic duty.
LCP
The local control panel makes up a complete interface for
control and programming of the frequency converter. The
LCP is detachable. With the installation kit option, the LCP
can be installed up to 3 m (9.8 ft) from the frequency
converter in a front panel.
NLCP
The numerical local control panel interface for control and
programming of the frequency converter. The display is
numerical and the panel is used to show process values.
The NLCP has storing and copy functions.
lsb
Least significant bit.
msb
Most significant bit.
MCM
Short for mille circular mil, an American measuring unit for
cable cross-section. 1 MCM = 0.5067 mm
2
.
On-line/off-line parameters
Changes to on-line parameters are activated immediately
after the data value is changed. To activate changes to off-
line parameters, press [OK].
Process PID
The PID control maintains speed, pressure, and
temperature by adjusting the output frequency to match
the varying load.
PCD
Process control data.
Power cycle
Switch off the mains until the display (LCP) is dark, then
turn power on again.
Power factor
The power factor is the relation between I
1
and I
RMS
.
Power factor =
3 x U x I
1
cosϕ1
3 x U x I
RMS
For FC 280 frequency converters,
cosϕ
1
= 1, therefore:
Power factor = I1 x cosϕ1
I
RMS
=
I
1
I
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
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 different
harmonic currents are low.
The built-in DC coils produce a high power factor,
minimizing the imposed load on the mains supply.
Pulse input/incremental encoder
An external, digital pulse transmitter used for feeding back
information on motor speed. The encoder is used in
applications where great accuracy in speed control is
required.
RCD
Residual current device.
Set-up
Save parameter settings in 4 set-ups. Change among the 4
parameter set-ups and edit 1 set-up while this set-up is
inactive.
SFAVM
Acronym describing the switching pattern stator flux-
oriented asynchronous vector modulation.
Slip compensation
The frequency converter compensates for the motor slip by
giving the frequency a supplement that follows the
measured motor load, keeping the motor speed almost
constant.
Smart logic control (SLC)
The SLC is a sequence of user-defined actions executed
when the smart logic controller evaluates the associated
user-defined events as true (
parameter group 13-** Smart
Logic Control
).
STW
Status word.
THD
Total harmonic distortion states the total contribution of
harmonic distortion.
Thermistor
A temperature-dependent resistor placed where the
temperature is monitored (frequency converter or motor).
Trip
Trip is a state entered in fault situations. Examples of fault
situations:
•
The frequency converter is subject to an over
voltage.
•
The frequency converter protects the motor,
process, or mechanism.
Restart is prevented until the cause of the fault has
disappeared, and the trip state is cancelled by activating
Introduction
VLT
®
Midi Drive FC 280
8
Danfoss A/S © 03/2016 All rights reserved.
MG07B102
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