Siemens SENTRON VL Series System Manual page 78

3WL air circuit breakers
3.5 External CubicleBUS modules
Switch position "I"
If the rotary coding switch is at switch position "I", the measured current values are output
linearly:
A01: Current in phase I
A02: Current in phase I
A03: Current in phase I
A04: Current in neutral conductor
Calculation of full-scale value
Since the circuit breaker can be designed for different rated currents, there must be
automatic scaling to the full-scale value, or interpretation of the maximum output value of the
analog output module. The value of the currently used rating plug is used for this.
The maximum value is calculated by multiplying the value of the rating plug by 1.2 and then
rounding up to the nearest 100.
Example: With a rating plug of 1600 A, the full-scale value of the rotary coil instrument must
be 2000 A (1600 x 1.2 = 1920 ⇒ 2000 A). That is, 0 V/4 mA correspond to 0 A, 10 V/20 mA
correspond to 2000 A.
Switch position "V"
If the rotary coding switch is at switch position "V", the following
voltages will be applied to the four analog outputs:
A01: External conductor voltage V
A02: External conductor voltage V
A03: External conductor voltage V
A04: Phase-to-neutral voltage V
In most cases, the external conductor voltages are indicated on the control cabinet doors.
For this reason, the first three channels are assigned these measured values. If the voltage
is required between a phase and the neutral conductor, it is available via the output.
The full-scale deflection value for the rotary coil instrument is derived by multiplying the rated
voltage of the system by 1.1 and then rounding up to the nearest 50 value.
Example: The rated voltage of the system is 400 V. The full-scale value is then 450 V
(400 V x 1.1 = 440 V ⇒ 450 V).
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L1
L2
L3
L12
L23
L31
L1N
3WL/3VL circuit breakers with communication capability - PROFIBUS
System Manual, 03/2011, A5E01051353-02