2.1 General
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7UT613/63x Manual
C53000-G1176-C160-2
Address 427 DMT 1PHASE AT assigns the single-phase time overcurrent protection 
(section 2.7). This protection function is mainly used for high-sensitivity current mea-
surement, e.g. for tank leakage protection or high-impedance differential protection. 
Therefore a high-sensitivity 1-phase additional measuring input is particularly suited 
for it. In figure 2-2 this would be the auxiliary measuring location X4; so you set this 
address to AuxiliaryCT IX4. However, it is also possible to assign this protection 
function to any other additional measuring input used, regardless of its sensitivity.
2.1.4.4 Circuit Breaker Data 
Circuit Breaker 
Status
Various protection and ancillary functions require information on the status of the 
circuit breaker for faultless operation. Command processing makes also use of the 
feedback information from the switching devices.
If, for instance, the circuit breaker failure protection is used to monitor the reaction of 
a specific circuit breaker (CB), the protection device must know the measuring location 
at which the current flowing through the breaker is acquired, and the binary inputs 
which provide information on the breaker status. During the configuration of the binary 
inputs you merely assigned the (physical) binary inputs to the (logic) functions. The 
device, however, must also know to which measuring location(s) the circuit breaker is 
assigned.
The breaker failure protection — and thus the circuit breaker that is monitored by it — 
is normally assigned to a measuring location or to a side (see above, under margin 
heading „Further 3-Phase Protection Functions“). You can therefore set addresses 
831 to 835 SwitchgCBaux S1 to SwitchgCBaux S5 if a side is concerned, or ad-
dresses 836 to 840 SwitchgCBaux M1 to SwitchgCBaux M5 if a measuring loca-
tion is concerned. 
You can, alternatively, monitor any desired circuit breaker, exclusively by means of the 
CB position indication, i.e. without consideration of current flow. In this case you must 
have selected 470 under address BREAKER FAIL.AT Ext. switchg. 1. You have 
then to select the corresponding breaker feedback information under address 841 
SwitchgCBaux E1 (switching device auxiliary contact of external breaker).
Select the address which corresponds to the assignment of the circuit breaker failure 
protection. There, you choose from the following options:
1. If during the configuration of the binary inputs you have defined the circuit breaker 
as a control object, and allocated the appropriate feedback indications, you 
choose these feedback indications to determine the circuit breaker position, e.g. 
„Q0“. The breaker position is then automatically derived from the circuit breaker 
Q0.
2. If during the configuration of the binary inputs you have generated a single-point 
indication which is controlled by the NC or NO auxiliary contacts of the circuit 
breaker, you select this indication.
3. If during the configuration of the binary inputs you have generated a double indi-
cation which is controlled by the NC or NO auxiliary contact of the circuit breaker 
(feedback from the protected object), you select this indication.
4. If you have generated appropriate indications using CFC, you can select these in-
dications.
In any case, you must make sure that the selected option indicates also the position 
of the monitored circuit breaker. If you have not yet generated an indication for control 
and feedback of the breaker to be monitored you should do so now. Detailed informa-
tion is given in the SIPROTEC 4 System Description.