msb
Most significant bit.
NLCP
Numerical Local Control Panel LCP101
On-line/Off-line Parameters
Changes to on-line parameters are activated immediately
after the data value is changed. Changes to off-line
parameters are not activated until you enter [OK] on the
LCP.
PID Controller
The PID controller maintains the desired speed, pressure,
temperature, etc. by adjusting the output frequency to
match the varying load.
RCD
Residual Current Device.
Set-up
You can save parameter settings in four set-ups. Change
between the four parameter set-ups, and edit one set-up,
while another set-up is active.
SFAVM
Switching pattern called Stator Flux-oriented Asynchronous
Vector Modulation (
14-00 Switching Pattern
).
Slip Compensation
The Adjustable frequency drive 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 associated user defined events are evaluated as
true by the SLC.
Thermistor:
A temperature-dependent resistor placed where the
temperature is to be monitored (Adjustable frequency
drive or motor).
Trip
A state entered in fault situations, e.g., if the Adjustable
frequency drive is subject to an overtemperature or when
the Adjustable frequency drive 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 Adjustable
frequency drive is protecting itself and requiring physical
intervention, e.g., if the Adjustable frequency drive is
subject to a short circuit on the output. A locked trip can
only be canceled by cutting off line power, removing the
cause of the fault, and reconnecting the Adjustable
frequency drive. Restart is prevented until the trip state is
cancelled by activating reset or, in some cases, by being
programmed to reset automatically. The trip-lock function
may not be used as a personal safety measure.
VT Characteristics
Variable torque characteristics used for pumps and fans.
VVC
plus
If compared with standard voltage/frequency ratio control,
Voltage Vector Control (VVC
plus
) improves the dynamics
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
).
1.1.7 Power Factor
The power factor is the relation between I
1
and I
RMS
.
Power factor =
3 ×
U × I1 × COSϕ
3 ×
U × IRMS
The power factor for 3-phase control:
=
I1 × cosϕ1
IRMS
=
I1
IRMS
since cosϕ1 = 1
The power factor indicates to which extent the Adjustable
frequency drive imposes a load on the line power supply.
The lower the power factor, the higher the I
RMS
for the
same kW performance.
IRMS = I1
2 + I
5
2 + I
7
2 + . . + In2
In addition, a high power factor indicates that the different
harmonic currents are low.
The built-in DC coils in the adjustable frequency drive
produce a high power factor, which minimizes the
imposed load on the line power supply.
How to Read this Design Gui...
VLT
®
HVAC Drive Design Guide
MG11BB22 - VLT
®
is a registered Danfoss trademark
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