hager h3+ - Page 56

56 6LE005550A
Function of the Energy trip unit
3.3 Measurement function
Setting the power sign convention
The power sign convention parameter is used to configure the power sign according
to the supply direction of the Energy circuit breaker.
Positif
Négatif
Power sign
P sign convention Default setting
Positive - negative Positive
Configuring this convention correctly enables the 4 quadrant set-up to be respected:
- Positive active power when the downstream equipment operates as a receiver
- Reactive power, on the one hand with the same sign as active power when the
equipment downstream is inductive, on the other hand with the opposite sign
when the equipment downstream is capacitive
P < 0 P > 0
Q > 0
Ii
Capacitive
(lead or ahead)
I
Inductive
(lag or delay)
Q < 0
III
Inductive
(lag or delay)
IV
Capacitive
(lead or ahead)
Setting the reactive and apparent power calculation convention
This parameter is used to configure the convention for calculating total reactive
power and total apparent power.
The calculation of these two variables will not lead to the same value as it depends
on whether the addition of the phase components is vectorial or arithmetic.
The following figure clearly shows the dierence in the case of total apparent power:
S
a
P
a
Q
a
Q
b
Q
c
P
b
P
c
S
b
S
c
S
v
S
v
S
A
Vector and arithmetic addition
Positive
Negative