ComAp InteliPro, Инструкция по установке и эксплуатации, Страница: 37 / 105

InteliPro, SW version 1.4, © ComAp – April 2014
InteliPro 1.4 Comprehensive Guide - rev. 1
2-15
The provided ANSI51 curve shapes are multiplied by the time multiplier, set by the setpoint I> T Del .
This way, the final shape of the tripping curve is calculated. See the example of the ANSI Moderately
Inverse curve multiplied by various time multipliers:
Time multiplier - ANSI Moderately Inverse
0,01
0,1
1
10
100
1000
0,01 0,1 1 10 100
I/Inom
de
la
y
[
s
e
c
] multiplier 10
multiplier 5
multiplier 1
multiplier 0.1
I
MPORTANT
:
Please note that InteliPro current measurement inputs range is 5A with over-range up to 9A.
This range provides possibility of ANSI 51 curves calculation up to cca 2x In case that 5A CT
secondary current is used. To allow evaluation of higher currents and appropriate delays according to
the mentioned curves, we recommend using lower secondary rating of the current transformers
(typically 1A) and then setting the current ratio accordingly. Please note, that this solution though
decreases the accuracy of the measurement, which is designed for the 5A CT output.
Time overcurrent with voltage control and restraint (ANSI 51V)
The voltage control of time overcurrent assures that the protection is blocked in case that the
measured voltage is above the level set by the setpoint
I> V: I> V Control .
The voltage restraint function is a modification of the IDMT overcurrent protection. It uses the same
mechanism of the delay calculation according to the IDMT trip curve, but the delay is further adjusted
according to the measured voltage: