BS 6353:1983

Foreword
Committees responsible
Specification
1. Scope
2. Definitions
3. Electrical interface characteristics
4. Interconnection facilities
5. Tone signals
6. Transmission distance
7. Marking
8. Documentation
Appendices
A. Design of safety couplers and barriers
B. Cable
Table
1. Electrical interface characteristics
Figures
1. Underground loudspeaker communication system
2. System electrical parameters
3. Safety coupler
4. Safety barrier

Specifies electrical interface characteristics, interconnection facilities, tone signals and transmission distance.

This British Standard specifies requirements for underground loudspeaker communication systems that are equipped with the facility for connecting speech and other audio signals to another loudspeaker communication system and/or to an appropriate surface switchboard to form a loudspeaker communication network.

Electrical input and output characteristics of underground loudspeaker communication systems necessary to achieve operational compatibility when they are interconnected are specified.

The requirements for tone signals specified in clause 5 do not apply to signals that are not transmitted to another system.

This standard is applicable to underground loudspeaker communication systems that are intended to be certified intrinsically safe for use in coal mines in accordance with BS 5501-9 for group I category “ia” systems.

This standard is not applicable to mine telephone systems.

NOTE 1 Further requirements for intrinsic safety are specified in BS 1259 and BS 5501-7.

NOTE 2 The titles of the publications referred to in this standard are listed on the inside back cover.