BS 6556-1:1985
Current
The latest, up-to-date edition.
Low speed digital signals for use in coal mines. Specification for optical coupling
Hardcopy , PDF
English
31-01-1985
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Foreword
Committees responsible
Specification
1 Scope
2 Definitions
3 General conventions
4 Data link configurations
5 Channel allocation
6 Data rate
7 Electrical network parameters
8 System performance
9 Cable connections
10 Environment
11 Maximum output parameters
12 Marking
13 Documentation
Appendix
A Cable parameters used for system performance test
Figures
1 Simplex operation
2 Duplex point-to-point operation
3 Multi-drop operation
4 Originate channel
5 Answer channel
6 Core configuration of cable
Defines electrical input and output characteristics of intrinsically safe transmitting and receiving circuits forming a low speed digital data transmission link in which data is transmitted using current loop techniques.
| Committee |
W/-
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| DevelopmentNote |
Supersedes 82/76934 DC and 88/70376 DC (09/2005) Reviewed and confirmed by BSI, January 2011. (12/2010)
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| DocumentType |
Standard
|
| Pages |
14
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| PublisherName |
British Standards Institution
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| Status |
Current
|
This Part of BS 6556 specifies the electrical input and output characteristics for the optical coupling of intrinsically safe transmitting and receiving circuits for use in coal mines. These form a low speed digital data transmission link in which data is transmitted using current loop techniques.
A data transmission system comprises a master and up to eight physical slaves so arranged that the transmission line is energized only from the master and galvanic isolation is achieved by optical coupling at each slave.
NOTE 1 Each physical slave may support more than one addressable logical slave as specified in Part 3 of this standard up to a maximum of 15 addressable slaves for the complete system.
This Part of BS 6556 only applies to apparatus where the circuits connected to the transmission lines are designed to be intrinsically safe in accordance with BS 1259, BS 5501-7 or BS 5501-9 as appropriate.
NOTE 2 Where apparatus, which is intended to be used in potentially explosive atmospheres, contains other circuits which are not intrinsically safe, those circuits will have to be given an alternative form of protection in accordance with BS 229, BS 4683 or BS 5501 as appropriate.
NOTE 3 The titles of the publications referred to in this standard are listed on the inside back cover.
| BS 6556-2:1985 | Low speed digital signals for use in coal mines Specification for transformer coupling |
| BS 6556-3:1985 | Low speed digital signals for use in coal mines Specification for message protocols |
| BS 6704:1996 | Code of practice for selection, installation and maintenance of intrinsically safe electrical equipment in coal mines |
| BS 4683-3:1972 | Specification for electrical apparatus for explosive atmospheres Type of protection N |
| BS 5501-9:1982 | Electrical apparatus for potentially explosive atmospheres Specification for intrinsically safe electrical systems \'i\' |
| BS 5501-7:1977 | Electrical apparatus for potentially explosive atmospheres Intrinsic safety \'i\' |
| BS 6556-2:1985 | Low speed digital signals for use in coal mines Specification for transformer coupling |
| BS 4683-1:1971 | Specification for electrical apparatus for explosive atmospheres Classification of maximum surface temperatures |
| BS 1442:1969 | Specification for galvanized mild steel wire for armouring cables |
| BS 4683-2:1971 | Specification for electrical apparatus for explosive atmospheres The construction and testing of flameproof enclosures of electrical apparatus |
| BS 5754:1987 | Specification for electrical analogue and state signals for use in coal mines |
| BS 6556-3:1985 | Low speed digital signals for use in coal mines Specification for message protocols |
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