![Siemens 7SR158 Argus Technical Manual Download Page 178](http://html.mh-extra.com/html/siemens/7sr158-argus/7sr158-argus_technical-manual_383099178.webp)
Chapter 6) 7SR158 Commissioning & Maintenance Guide
Chapter 6 - Page 16 of 24
©2013 Siemens Protection Devices Limited
2.1.5
Vector Shift (78)
Voltage Inputs:
‘Van,Vbn,Vcn’ or ‘Vab,Vbc,3V0’.
Disable:
81, 81R
Map Pickup LED:
78-n - Self Reset
Vector shift is a 3-phase protection and therefore test voltages must be applied to all VT inputs. Elements with the
highest pick-up setting should be tested first. The elements with lower pick-up settings can then be tested without
the need to disable the elements already tested.
To test operation of the 78 elements, it is necessary to step change the phase ‘jump’ in the voltage waveform.
The size of the jump is increased with each with test step until the element operates. Being instantaneous, there
should be no difference between the element picking-up and operating. Therefore the 78-n output contact can be
used for both pick-up and timing measurements.
Voltage
Vector Shift
(°)
P.U.
Phase Step
(°)
Operate
Time
(sec)
UV
Guard
NOTES
The applied voltage must be above the
78 UV Guard (Ph-N0 Setting
in the
Vector Shift
menu for the element to
operate.
This setting can be tested by applying the test voltage at a level below the
78 U/V Guard Setting
at a vector shift
in the operate range. Increase the voltage until the relay operates.
UVG
Setting
(Volts)
Vector Shift
element
Used for test
Blocked
Vector Shift
(D.O.)
Unblocked
Vector Shift
(P.U.)
NOTES
Check correct indication, trip output, alarm contacts, waveform record.
2.1.5.1 Element Blocking
The vector shift elements can be blocked by Binary Input Inhibit. This functionality should be checked.
Element
BI Inhibits
78-1
78-2
When testing is complete reinstate any of the disabled functions.
Summary of Contents for 7SR158 Argus
Page 1: ...Answers for energy 7SR158 Argus Voltage and Frequency Relay Reyrolle Protection Devices ...
Page 2: ......
Page 4: ...7SR158 Argus Contents ...
Page 211: ......