7SR21 & 7SR22 - Installation Guide
Section 2: Equipment Operating
Conditions
2.1
Current Transformer Circuits
The secondary circuit of a live CT must not be open circuited. Non-observance of this precaution can result in
injury to personnel or damage to equipment.
!
2.2
External Resistors
!
Where external resistors are fitted to relays, these may present a danger of electric shock or burns, if touched.
!
2.3
Fibre Optic Communication
Where fibre optic communication devices are fitted, these should not be viewed directly. Optical power meters
should be used to determine the operation or signal level of the device.
2.4
Front Cover
!
The front cover provides additional securing of the relay element within the case. The relay cover should be in
place during normal operating conditions.
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©2011 Siemens Protection Devices Limited
