Current Transformer Circuits; Fibre Optic Communication; Front Cover; Disposal - Siemens Argus 7SR21 Technical Manual

7SR210 & 7SR220 Description of Operation

Section 1: Introduction

This manual is applicable to the following relays:
·
7SR210 Multi-Function Non-directional Overcurrent and Earth Fault Relay
·
7SR220 Multi-Function Directional Overcurrent and Directional Earth Fault Relay
The 7SR210 and 7SR220 relays integrate the protection and control elements required to provide a complete
overcurrent based protection.
The 'Ordering Options' Tables summarise the features available in each model.
General Safety Precautions

1.1 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.
1.2 External Resistors
!
Where external resistors are fitted to the circuit, these may present a danger of electric shock or burns, if touched.

1.3 Fibre Optic Communication

!
Where fibre optic communication ports are fitted, the lasers are Class 1 devices but recommend they should not
be viewed directly. Optical power meters should be used to determine the operation or signal level of the device.

1.4 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.

1.5 Disposal

The Relay should be disposed of in a manner which does not provide a threat to health or the environment. All
laws and regulations specific to the country of disposal should be adhered to.
!
The relays and protection systems manufactured under the Reyrolle brand currently do not come within the scope
of either the European WEEE or RoHS directives as they are equipment making up a fixed installation.
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