• There are no items in your cart

BS 6556-3:1985

Current

Current

The latest, up-to-date edition.

Low speed digital signals for use in coal mines Specification for message protocols

Available format(s)

Hardcopy , PDF

Language(s)

English

Published date

01-31-1985

Foreword
Committees responsible
Specification
0 Introduction
1 Scope
2 Definitions and abbreviations
3 Link configurations
4 Transmissions
5 Checks
6 Data only protocol (DOP)
7 Simple asynchronous protocol (SAP)
8 Marking
Appendix
A Method for the generation and verification of check
    field (CF)
Tables
1 Start of message (SMB) codes
2 Valid address bytes
3 Stuffing codes
Figures
1 The components of the byte transmission
2 Operation using DOP
3 Operation for 1 to 15 slaves using SAP
4 Application data message (ADM) and broadcast message
    (BRO) format
5 Link control message (LCM) and initialization
    message (IM) format
6 A 2 byte transmission
7 Transmission envelope from slave with modem
8 Slave response to poll (current loop link)
9 Slave response to poll (MODEM link)
10 Composition of message address byte (AB)
11 Composition of application data description byte
    (ADD)

Specifies the message protocols employed with intrinsicaly safe transmitting and receiving circuits forming low speed digital data transmission links in which the data is transmitted by optical or transformer couplings.

This Part of BS 6556 specifies two message protocols employed with particular low speed digital signals systems for use in coal mines, using either optical coupling (see BS 6556-1) or transformer coupling (see BS 6556-2). Either protocol can be employed in either transmission system.

The protocols require only limited station intelligence for successful implementation. One protocol, known as simple asynchronous protocol, is designed to work in point-to-point or multi-drop configurations. The other protocol, known as data only protocol, will only work in point-to-point configurations.

Protocol for the applications data is not specified by this standard although industry standards will exist to regulate this.

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

Committee
W/-
DevelopmentNote
Supersedes 82/76936 DC and 88/70378 DC (09/2005) Reviewed and confirmed by BSI, January 2011. (12/2010)
DocumentType
Standard
Pages
26
PublisherName
British Standards Institution
Status
Current

BS 6556-2:1985 Low speed digital signals for use in coal mines Specification for transformer coupling
BS 6704:1996 Code of practice for selection, installation and maintenance of intrinsically safe electrical equipment in coal mines
BS 6556-1:1985 Low speed digital signals for use in coal mines. Specification for optical coupling
BS EN 322:1993 Wood-based panels. Determination of moisture content

BS 6556-1:1985 Low speed digital signals for use in coal mines. Specification for optical coupling
BS 5754:1980 Specification for electrical analogue and state signals for use in coal mines
BS 6556-2:1985 Low speed digital signals for use in coal mines Specification for transformer coupling
BS 5397(1984) : LATEST

View more information
US$222.80
Excluding Tax where applicable

Access your standards online with a subscription

Features

  • Simple online access to standards, technical information and regulations.

  • Critical updates of standards and customisable alerts and notifications.

  • Multi-user online standards collection: secure, flexible and cost effective.