Trip Circuit Supervision 74Tc; Description - Siemens SIPROTEC 4 User Manual

No. Information
197 MeasSup OFF
253 VT brk. wire
255 Fail VT circuit
256 VT b.w. 1 pole
257 VT b.w. 2 pole
258 VT b.w. 3 pole
6509 >FAIL:FEEDER VT
6510 >FAIL: BUS VT

Trip Circuit Supervision 74TC

2.12.2
Devices 7SJ62/64 are equipped with an integrated trip circuit supervision. Depending on the number of avail-
able binary inputs (not connected to a common potential), supervision with one or two binary inputs can be
selected. If the allocation of the required binary inputs does not match the selected supervision type, then a
message to this effect is generated (
Applications
•
When using two binary inputs, malfunctions in the trip circuit can be detected under all circuit breaker
conditions.
•
When only one binary input is used, malfunctions in the circuit breaker itself cannot be detected.
Prerequisites
A requirement for the use of trip circuit supervision is that the control voltage for the circuit breaker is at least
twice the voltage drop across the binary input (V
Since at least 19 V are needed for the binary input, the supervision can only be used with a system control
voltage of over 38 V.
2.12.2.1

Description

Supervision with Two Binary Inputs
When using two binary inputs, these are connected according to
contact on one side, and parallel to the circuit breaker auxiliary contacts on the other.
SIPROTEC 4, 7SJ62/64, Manual
C53000-G1140-C207-8, Edition 08.2016
Type of Comments
Informa-
tion
OUT Measurement Supervision is switched OFF
OUT Failure VT circuit: broken wire
OUT Failure VT circuit
OUT Failure VT circuit: 1 pole broken wire
OUT Failure VT circuit: 2 pole broken wire
OUT Failure VT circuit: 3 pole broken wire
SP >Failure: Feeder VT
SP >Failure: Busbar VT
74TC ProgFail ).
> 2 · V ).
Ct BImin
2.12 Monitoring Functions
Figure 2-76, parallel to the associated trip
Functions
193