Siemens Argus 7SR21 Technical Manual page 562

7SR210 & 7SR220 Commissioning & Maintenance Guide
2.10.2 Undervoltage Guard (27/59UVG)
If any 27 Undervoltage element is set to be inhibited by the 27 Undervoltage Guard element, this function should
be tested.
Connect the test voltage inputs to suit the installation wiring diagram utilising any test socket facilities available. It
may be useful to temporarily map an LED as 'General Pickup' to assist during testing. 27UVG operation will reset
the General Pickup if no other element is operated. This LED should not be set as 'Hand Reset' in the Output
matrix.
Starting from nominal voltage, apply a step decrease to the applied voltage to a level below the 27 Undervoltage
setting but above the 27UVG setting such that an Undervoltage element operation occurs. Slowly reduce the
applied voltage until the 27 Undervoltage element resets, this can be detected by the General Pickup LED reset if
no other element is operated (this includes any Undervoltage element which is not UV Guarded).
Vs V element Blocked
Phase Tol NOTES
(Volts) Used for test Volts
UVG
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