ABB Relion 611 Series, Technical Manual

Page: 336 / 536

A070785 V2 EN
Figure 159: Functional module diagram
TCS status
This module receives the trip circuit status from the hardware. A detected failure in the
trip circuit activates the timer.
Timer
Once activated, the timer runs until the set value of Operate delay time has elapsed.
The time characteristic is according to DT. When the operation timer has reached the
maximum time value, the
ALARM
output is activated. If a drop-off situation occurs
during the operate time up counting, the fixed 0.5 s reset timer is activated. After that
time, the operation timer is reset.
The
BLOCK
input can be controlled with a binary input, a horizontal communication
input or an internal signal of the relay program. The activation of the
BLOCK
input
prevents the
ALARM
output to be activated.
6.1.5 Application
TCSSCBR detects faults in the electrical control circuit of the circuit breaker. The
function can supervise both open and closed coil circuits. This supervision is
necessary to find out the vitality of the control circuits continuously.
Figure 160 shows an application of the trip circuit supervision function use. The best
solution is to connect an external R
ext
shunt resistor in parallel with the circuit breaker
internal contact. Although the circuit breaker internal contact is open, TCS can see the
trip circuit through R
ext
. The R
ext
resistor should have such a resistance that the current
through the resistance remains small, that is, it does not harm or overload the circuit
breaker's trip coil.
Section 6
1MRS757454 D
Supervision functions
330 611 series
Technical Manual