Micom P631, Technical Manual, Page: 179 / 638

3.22 Definite-Time Overcurrent Protection (Function Groups
DTOC1 and DTOC2)
In the P631, a three-stage definite-time overcurrent protection function (DTOC
protection) is available. The measured values to be monitored by the respective
DTOC functions are selected using a setting parameter.
Phase current values as well as negative-sequence and residual current
measured values are monitored.
The function group DTOC1 will serve as an example to illustrate the operation of
the DTOC protection functions. The same will apply to function group DTOC2.
62Z5070A
DTOC1:
Select. meas. input
[ 019 103 ]
0
1
0: End a
1: End b
0 , 1
I̲A,y
I̲B,y
I̲C,y
I̲N,y
I̲A,a
I̲B,a
I̲C,a
I̲N,a
I̲A,b
I̲B,b
I̲C,b
I̲N,b
Fig. 3-90: Selection of measured values for DTOC protection
3.22.1 Enabling or Disabling DTOC Protection
DTOC protection can be enabled or disabled using setting parameters. Moreover,
enabling can be carried out separately for each parameter set.
3 Operation
P631
P631/EN M/R-11-C // P631-310-650 3-123