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Chapter 7) 7SR23 DAD Applications Guide
©2013 Siemens Protection Devices Limited
Chapter 7 Page 24 of 42
Section 4: Control Functions
4.1
Zone
Switching
Figure 4-1
Logic Diagram: Protection In/Out Switching
When commissioning and testing of circuit protections e.g. feeder overcurrent protection it is necessary to carry
out primary injection testing. At such times it is necessary to short circuit the secondary windings of the busbar
protection CTs on that circuit otherwise a differential trip might result.
Alternatively the busbar protection can be switched out using the zone switch-out facility, this will inhibit operation
of the differential elements, the CT supervision elements and also apply zone CT shorting.
Summary of Contents for 7SR23 DAD
Page 1: ...Answers for energy 7SR23 DAD High Impedance Protection Relay Reyrolle Protection Devices ...
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Page 4: ...7SR23 DAD Contents 2013 Siemens Protection Devices Limited ...
Page 60: ...Chapter 3 7SR23 DAD Performance Specification 2013 Siemens Protection Devices Limited ...
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