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Analog Output Module
The analog output module can be
used to output the most important
measured values sent via the
CubicleBUS to analog indicators (e.g.
analog meters) in the switchgear
cubicle door. Each analog output
module has four channels for this
purpose. The signals are available at
two physical interfaces: a 4 ... 20mA
and a 0 ... 10V interface.
The measured values are available
as 0 ... 10V via the X4 connector
on the CubicleBUS module (the 4 ...
20mA interface is available at X5).
Both outputs are always active at
the same time, and can be used
simultaneously.
The measured values, which are
output via the four channels, are
selected using a rotary switch.
The available outputs are current,
voltage, power, frequency and
power factor. Up to two analog
output modules can be operated on
one CubicleBUS. The selection panel
on the rotary switch is divided
vertically. If the switch is set to a
value on the left, the module is
automatically addressed as module 1.
If a second module exists, it must
be set to a value on the right. This
is the only way that two analog
output modules can operate
simultaneously.
All types of analog instruments with
an internal resistance of more than
20kΩ (for the voltage output) and
between 50Ω and 250Ω (as a
current output) can be used as
an indicator.
The LEDs for the channels are
yellow if the current value exceeds
the full-scale deflection by 20%
(with V, I and P), power factor is
greater than 0.8, or the frequency
greater than 45Hz.
Switch position "I"
In switch position "I", the measured
current values are output linearly:
A01: Current in phase A
A02: Current in phase B
A03: Current in phase C
A04: Current in the neutral
conductor
WL PROFIBUS Communication and Electronic Accessories • July 2004
Communication-capable Circuit Breakers
Since the circuit breaker can
be designed for different rated
currents, the full-scale value must
be scaled automatically and the
maximum output value of the
analog output module interpreted.
The value of the rating plug is used
for this purpose.
The maximum value is calculated by
multiplying the value of the rating
plug by 1.2 and then rounding the
result up to the nearest 100.
Example: With a rating plug of
1600A, the full-scale value of the
analog panel meter must be 2000A
(1600 x 1.2 = 1920 -> 2000A). In
other words, 0V/4mA = 0A,
10V/20mA = 2000A.
Switch position "U"
When the rotary switch is in switch
position "U", the following voltages
are applied to the four analog
outputs:
A01: Phase-to-phase voltage V
A02: Phase-to-phase voltage V
A03: Phase-to-phase voltage V
A04: Phase voltage V
N
In most cases, the phase-to-phase
voltage is output to the switchgear
cubicle doors. This is why the first
three channels are assigned these
measured values. If the voltage is
required between a phase and the
neutral conductor, this is available
via output A04.
The full-scale deflection for the
analog panel meter is calculated
by multiplying the rated voltage
of the network (primary voltage
of the voltage transformer) by 1.1
and then rounding the result up to
the nearest 50.
Example: If the rated voltage of the
network is 480V, the full-scale value
is 550V (480V x 1.1 = 528V ->
550V).
Switch position "P"
If the rotary switch is set to position
"P", the power measured values are
output via the four channels:
WL Circuit Breaker
A01: Active power phase kW
A02: Active power phase kW
A03: Active power phase kW
A04: Total apparent power kVA
The full-scale deflection of the
active power in each phase is
calculated by multiplying the
value of the rating plug by the
rated voltage of the network.
The full-scale deflection value
is then classified in a value range,
as shown in the table below.
Before the full-scale deflection can
be determined from the table, the
calculated value must be multiplied
by 3 for the total apparent power and
the total active power (position f).
Example: I
= 1600A, rated voltage
R
= 480V; -> full-scale deflection =
1,000,000 W
Switch position "f"
Since it can generally be assumed
that the frequency will be the same
ab
across the three phases in all the
bc
networks, switch position "f" is
ca
used to provide a general overview
by outputting the most important
measured values (with the exception
of the current values). In conjunction
with another module in position "I",
all the most important measured
values can be displayed in this way.
Power value ranges [W/VA]
From
To
0
50,000
50,000
100,000
100,000
200,000
200,000
300,000
300,000
500,000
500,000
1,000,000
1,000,000
2,000,000
2,000,000
3,000,000
3,000,000
5,000,000
5,000,000
10,000,000
10,000,000
20,000,000
20,000,000
∞
Table 2-20
After multiplication, the full-scale
deflection of the power is sorted into ranges.
a
b
c
TOT
Full Scale Deflection
50,000
100,000
200,000
300,000
500,000
1,000,000
2,000,000
3,000,000
5,000,000
10,000,000
20,000,000
30,000,000
2/28
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