f
MIN
Minimum compressor frequency.
f
jog
Motor frequency when the jog function is activated (via digital terminals).
I
I
M
Motor current (actual).
I
M,N
Rated motor current (nameplate data).
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.
L
lsb
Least significant bit.
M
MCM
Short for "mille circular mil", an American measuring unit for cable cross-
section. 1 MCM=0.5067 mm
2
msb
Most significant bit.
N
n
M,N
Nominal motor speed (nameplate data).
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
PI controller
The PI controller maintains the required speed, pressure, temperature, and
so on, by adjusting the output frequency to match the varying load.
P
M,N
Rated motor power (nameplate data in kW or hp).
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.
AJ330233902305en-000201/130R0596
74 | Danfoss A/S © 2021.05
Glossary
VLT® Compressor Drive CDS 803
Design Guide