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5.4 Trip Circuit Supervision
Trip Circuit Supervision (TCS) enables the trip circuit to be monitor. To enable TCS function, set
one of the Digital Input function to TCS (at the INPUT Menu), Input Type as Active High and set
the appropriate TCS delay time.
The continuity of trip circuit is monitor when Trip contact R1 is not energized. When the input
detects no signal for a time longer than the TCS delay time, TCS alarm pops up to warn the failure
of trip circuit. Three examples of application are given below.
Example 1: Trip Coil Monitoring
In this example only 52a auxiliary contact is available; the trip coil is monitored when the CB is
open or closed.
Example 2: Trip Coil and Auxiliary Contacts Monitoring
In this example both 52a and 52b auxiliary contacts are available. The complete trip circuit is
monitored when the CB is closed and a part of the trip circuit when the CB is open (excluding Trip
coil).
It is necessary to insert resistor R1 in series with 52b, if the Trip contact R1 is latched or it stays
involuntarily closed.
+ Vdc
-Vdc
52a
38 37
MK2200H
Trip coil
Trip contact
R1
Digital
Input
MK3000L
- Vdc
52a
52b
Trip coil
Resistor R1
+ Vdc
38 37
MK2200H
Trip contact
R1
Digital
Input
MK3000L
