O
Online/offline parameters
Changes to online parameters are activated immediately after the data val-
ue is changed. Press [OK] to activate changes to off-line parameters.
P
PCD
Process-control data.
PDS
The PDS is a speed control system for an electric motor, including the CDM
and motor, but without the equipment which it powers.
P
M,N
Rated motor power (nameplate data in kW or hp).
Position error
Position error is the difference between the actual position and the com-
manded position. The position error is the input for the position PI control-
ler.
Position unit
The physical unit for position values.
Power factor
The power factor is the relation between I
1
and I
RMS
.
Power factor =
3 ×
U
×
I
1cos
ϕ
3 ×
U
×
I
RMS
The power factor for 3-phase control:
Power factor =
I
1
× cos
ϕ
1
I
RMS
=
I
1
I
RMS
since cos
ϕ
1 = 1
The power factor indicates to which extent the drive imposes a load on the
mains supply.
The lower the power factor, the higher the I
RMS
for the same kW perform-
ance.
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 cur-
rents are low.
The DC coils in the drive produce a high-power factor, which minimizes the
imposed load on the mains supply.
Preset reference
A defined preset reference to be set from -100% to +100% of the reference
range. Selection of 8 preset references via the digital terminals.
Process PID
The PID control maintains the required speed, pressure, temperature, and
so on, by adjusting the output frequency to match the varying load.
Pulse reference
A pulse frequency signal transmitted to the digital inputs (terminal 29 or
33).
R
RCD
Residual-current device.
S
STW
Status word.
Safe Torque Off (STO)
The STO function brings the drive safely to a no-torque state.
Set-up
Save parameter settings in 4 set-ups. Change between the 4 parameter set-
ups and edit 1 set-up, while another set-up is active.
Slip compensation
The drive compensates for the motor slip by giving the frequency a supple-
ment that follows the measured motor load keeping the motor speed al-
most constant.
AU373327181955en-000101/130R1208
376 | Danfoss A/S © 2021.08
Glossary
VLT® AutomationDrive EZ FC 321
Programming Guide