7SR210 & 7SR220 Description of Operation
Unrestricted Page 78 of 94
©2018 Siemens Protection Devices Limited
5.2
VT Supervision (60VTS) – 7SR22
1 or 2 Phase Failure Detection
Normally the presence of negative phase sequence (NPS) or zero phase sequence (ZPS) voltage in a power
system is accompanied by NPS or ZPS current. The presence of either of these sequence voltages without the
equivalent level of the appropriate sequence current is used to indicate a failure of one or two VT phases.
The
60VTS Component
setting selects the method used for the detection of loss of 1 or 2 VT phases i.e.
ZPS
or
NPS
components. The sequence component voltage is derived from the line voltages; suitable VT connections
must be available. The relay utilises fundamental voltage measurement values for this function.
The element has user settings
60VTS V
and
60VTS I.
A VT is considered to have failed where the voltage
exceeds
60VTS V
while the current is below
60VTS I
for a time greater than
60VTS Delay
.
3 Phase Failure Detection
Under normal load conditions rated PPS voltage would be expected along with a PPS load current within the
circuit rating. Where PPS load current is detected without corresponding PPS voltage this could indicate a three
phase VT failure. To ensure these conditions are not caused by a 3 phase fault the PPS current must also be
below the fault level.
The element has a
60VTS V
PPS
setting, an
60VTS I
PPS
Load
setting and a setting for
60VTS I
PPS
Fault
. A VT is
considered to have failed where positive sequence voltage is below
60VTS V
PPS
while positive sequence current
is above
I
PPS
Load
and below
I
PPS
Fault
level for more than
60VTS Delay
then a VT failure will be detected.
External MCB
A binary input can be set as
Ext_Trig 60VTS
to allow the
60VTS Delay
element to be started from an external
MCB operating.
Once a VT failure condition has occurred the output is latched on and is reset by any of the following: -
Voltage is restored to a healthy state i.e. above
V
PPS
setting while NPS voltage is below
V
NPS
setting.
Ext Reset 60VTS
A binary or virtual input, or function key and a VT failure condition no longer
exists.
Inhibit 60VTS
A binary, virtual input, function key or remote data Comms.
Summary of Contents for Argus 7SR21
Page 1: ...Energy Management 7SR21 7SR22 Argus Overcurrent Relay Reyrolle Protection Devices ...
Page 2: ......
Page 4: ...Contents 7SR11 and 7SR12 Page 2 of 2 2018 Siemens Protection Devices Limited ...
Page 185: ...7SR210 Settings Guide Unrestricted 2018 Siemens Protection Devices Limited Page 61 of 61 ...
Page 277: ...7SR220 Settings Guide Unrestricted Page 72 of 107 2013 Siemens Protection Devices Limited ...
Page 382: ...7SR220 Technical Manual Chapter 4 Page 2 of 96 2017 Siemens Protection Devices Limited ...
Page 386: ...7SR220 Technical Manual Chapter 4 Page 6 of 96 2017 Siemens Protection Devices Limited ...
Page 398: ...7SR220 Technical Manual Chapter 4 Page 18 of 96 2017 Siemens Protection Devices Limited ...
Page 414: ...7SR220 Technical Manual Chapter 4 Page 34 of 96 2017 Siemens Protection Devices Limited ...
Page 466: ...7SR220 Technical Manual Chapter 4 Page 86 of 96 2017 Siemens Protection Devices Limited ...
Page 468: ...7SR220 Technical Manual Chapter 4 Page 88 of 96 2017 Siemens Protection Devices Limited ...
Page 470: ...7SR220 Technical Manual Chapter 4 Page 90 of 96 2017 Siemens Protection Devices Limited ...
Page 472: ...7SR220 Technical Manual Chapter 4 Page 92 of 96 2017 Siemens Protection Devices Limited ...
Page 643: ...Unrestricted ...