Section 2: Equipment Operating Conditions; Current Transformer Circuits; External Resistors; Fibre Optic Communication - Siemens Argus 7SR21 Installation Manual

Section 2: Equipment Operating
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.
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2.2

External Resistors

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Where external resistors are fitted to relays, these may present a danger of electric shock or burns, if touched.
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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.
©2010 Siemens Protection Devices Limited
Conditions
7SR21 & 7SR22 Argus Installation Guide
Chapter 5 Page 5 of 22