ABB EIB Delta, Руководство пользователя

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Active and reactive power: Capacitive or inductive loads cause a phase
angle shift between the phase current and phase voltage.
The maximum permitted phase angle shift is often contractually defined by
the power supply companies. So that the specified values are not exceeded,
power factor correction systems are often installed and the consumption is
monitored using reactive energy meters or combination meters.
So that energy consumption can be measured in installations with current and
voltage levels beyond the nominal measuring range of the EIB Delta-Meter, it is
necessary to use current and/or voltage transformers. It is important that the
secondary current and voltage of the measurement transformers, lie within the
permitted measuring ranges of the transformer rated meter. In order to
guarantee the required level of accuracy, the selected transformers should
have a higher accuracy class than the meter. The current transformers must be
connected with the correct polarity (K1
⇒
L1, k1
⇒
l1).
Note: The secondary measuring circuits of the transformers must be laid
separately to the main power cables to eliminate induced current errors.
The terminal block indicated above is not absolutely necessary for the
installation but simplifies servicing procedures.
2.2 Measurements with current
and voltage transformers
EIB Delta-Meter
Electricity Meters
8
ABB i-bus
®
EIB
Active power
Capacitive
load
Inductive
load
Apparent power
ϕ
Active power = U x I x cos
ϕ
Reactive power = U x I x sin
ϕ
Apparent power= U x I
2 3 5 7 8 9 1
k
L1
L2
l
K L
Terminal block
L3
k l
K L
e.g. Three-wire,
polyphase meter