EIB Delta-Meter
Electricity Meters
10
ABB i-bus
®
EIB
2.3 Calculation of energy
6
=
V
100
V
600
=
Secondary voltage (U
S
)
Primary voltage (U
P
)
=
VT
=
Secondary current (I
S
)
Primary current (I
P
)
=
CT
50
=
A
5
A
250
kW
141
=
6
50
0.47 kWh
=
VT
CT
s
P
=
p
P
•
•
•
•
Hz
0.65
=
3600
Imp/kWh
5000
0.47 kW
=
3600
Z
P
=
B
k
s
f
•
•
s
1.53
=
Hz
0.65
1
=
B
1
=
B
f
p
The energy consumption can be read out from the LCD display of the EIB
Delta-Meter and can also be recorded and processed remotely using the EIB
communication interface.
In the case of direct connected EIB Delta-Meters, the energy in the LCD
display is identical to the energy that has been consumed. If current and/or
voltage transformers have been used, the displayed consumption value must
be multiplied by the transformer ratio (CT x VT) in order to determine the
actual, primary energy consumption.
All transformer rated meters display secondary measured values.
The light-emitting diodes next to the meter readout and the LCD display
symbols [A] and [R], flash at a rate [Z
k
] of:
Direct connected meter
1000 Imp/kWh (kvarh)
Transformer rated meter
5000 Imp/kWh (kvarh)
The equations in the following example can be used in order to calculate the
LED/LCD flash rate at the given power.
Three-wire polyphase network with current and voltage transformers:
Type of current transformer:
250/5 A/A
Type of voltage transformer:
600/100 V/V
Secondary current (I):
3 A
Secondary voltage (U):
100 V
Power factor (cos
ϕ
):
0.9
Meter constant (LED, LCD) (Z
k
):
5000 Imp/kWh
Transformer ratio of voltage transformer (VT):
Transformer ratio of current transformer (CT):
Secondary power (P
s
):
Primary power (P
p
):
LED/LCD flash frequency (B
f
):
LED/LCD flash period (B
p
):
When connected correctly, the LED and the LCD display symbol [A] should
flash approx. every 1.5 seconds in the above example.
kW
0.47
=
1000
0.9
A
3
V
100
3
=
1000
cos
I
U
3
=
s
P
•
•
•
•
•
•
ϕ
