janitza UMG 511 Manual page 10

General
Under difference I
K-factor
• The K-factor describes the increase of the eddy current losses when loaded with harmonics. For a sinusoidal load on
the transformer, the K-factor =1. The larger the K-factor, the heavier a transformer can be loaded with harmonics wit-
hout overheating.
Power Factor (vectorial) - Lambda
• The power factor is unsigned.
CosPhi - Fundamental Power Factor
• Only the mains frequency part is used for calculati-
on of the cosphi.
• CosPhi sign:
- = for the supply of real power
+ = for obtaining real power
CosPhi total
• CosPhi sign:
- = for the supply of real power
+ = for obtaining real power
Phase Angle Phi
• The phase angle between current and voltage of the external conductor p is calculated according to DIN EN 61557-12
and displayed.
• The sign of the phase angle corresponding to the sign of the reactive power.
UMG 511
10
cos( ) ϕ =
Sum
3 ( P + P
1
fund
cos( ) ϕ =
Sum
(
4 P + P
1
fund
P
PF =
A
S
A
P
cos( ) ϕ
PF = =
1
1
S
1
P + P + P
1 2 3
fund fund fund
2
+ P ) + ( Q + Q
2 3 1
fund fund f f und
P + P + P
1 2 3
fund fund
2
+ P + P ) + ( Q
2 3 4
fund fun d d fund
2
+ Q )
2 3
fund fund
+ P
4
fund fund
+ Q + Q + Q
1 2 3 4
fund fund fund fund
2
)