7SR18 Performance Specification
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1.2.5.2 AC Performance
Attribute Value
Maximum peak current for
operation
V
BI
= 19 V 1.5 mA
Response time >115 V
RMS
AC < 16 ms
Response time when programmed to energise an
output relay contact (i.e. includes output relay
operation)
< 26 ms
For AC operation the BI pick-up delay should be set to 0 ms and the drop-off delay to 25 ms.
For AC operation wiring should be less than 10 metres in length.
1.3 Functional performance
1.3.1 Instrumentation
Instrument Value Reference Typical accuracy
I Current
0.1 xIn ≤ I ≤ 3.0 xIn ± 1 % In
V Voltage
0.8 xVn ≤ V ≤ 1.2 xVn ± 1 % Vn
W,Var,
VA
Power, real and apparent
V = Vn, I ≥ 0.1 xIn, pf ≥ 0.8 ± 3% Pn, where Pn = Vn x In
pf Power factor
V = Vn, I ≥ 0.1 xIn, pf ≥ 0.8 ± 0.05
F Frequency
F = 47.5 to 52.5Hz @ 50Hz
and 57 to 63Hz @60Hz
± 10mHz
1.3.2 Real Time Clock
1.3.2.1 Internal Clock
The specification below applies only while no external synchronisation signal (e.g. 60870-5-103) is being
received.
Attribute Value
Accuracy (-10
o
C to +55
o
C)
± 3.5 p.p.m