4.12 Analogue output (option)
4 Measurement functions
Technical description
150
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VM50.EN004
Example 4: Per unit to secondary. Voltage measurement mode
is "1LN".
VT = 12000/110
The relay displays 1.00 pu = 100 %.
Phase-to-neutral voltage connected to the relay's input is
U
SEC
= 1.00x110/
3x11000/12000 = 63.5 V
Per unit [pu] scaling of zero sequence voltage
Zero-sequence voltage (U
0
) scaling
Voltage measurement mode = "U
0
"
secondary
per unit
SEC
SEC
PU
U
U
U
0
per unit
secondary
SEC
PU
SEC
U
U
U
0
Example 1: Secondary to per unit. Voltage measurement mode
is "U
0
".
U
0SEC
= 110 V (This is a configuration value corresponding to
U
0
at full earth fault.)
Voltage connected to the relay's input is 22 V.
Per unit voltage is
U
PU
= 22/110 = 0.20 pu = 20 %
4.12.
Analogue output (option)
A device with the mA option has one configurable analogue
output. The resolution of the analogue output is 10 bits
resulting current steps less than 25
A. The output current
range is configurable allowing e.g. the following ranges: 0 .. 20
mA and 4 .. 20 mA. More exotic ranges like 0 … 5 mA or 10 …
2 mA can be configured freely as long as the boundary values
are within 0 … 20 mA.
Available couplings to the analog output:
IL1, IL2, IL2
F
IL
Io, IoCalc
U12 (only in VAMP52)
UL1 (only in VAMP52)