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Table of Contents
                            3.7 CABLE TERMINATIONS
“6.  PNEUMATIC TUBING
7.1 CABLE IDENTIFICATIONS
1. INTRODUCTION
1.1 SCOPE
1.2 DISTRIBUTION, APPLICABILITY AND REGULATORY CONSIDERATIONS
1.3  DEFINITIONS AND ABBREVIATIONS
1.4 CROSS REFERENCES
2.  ELECTRICAL CABLING
2.1  GENERAL

2.2 FUNDAMENTAL REQUIREMENTS
2.3  SIGNAL SEGREGATION IN MULTICORE CABLES
Table 1: Classification of Instrument Signal Levels
2.4  SELECTION AND SPECIFICATION OF INSTRUMENT CABLES
Table 2: Recommended Cable Types for Signals Level Classes 1/2/3 (Note 1)
2.5  CABLES FOR DIGITAL AND VIDEO SIGNALS
2.6  CABLES FOR SPECIAL APPLICATIONS

2.7  PROTECTION OF CABLES AGAINST FIRE DAMAGE
3.  CABLE SEGREGATION, ROUTING AND INSTALLATION
3.1 INSTALLATION ASPECTS
3.2 MOUNTING AND PROTECTION OF CABLES
3.3  CABLE SEGREGATION
3.4  ROUTING

3.5  JUNCTION BOXES FOR MULTICORE CABLES
3.6  CABLE GLANDS

3.7 CABLE TERMINATIONS
3.8  TRUNKING AND TRAYS
3.9 TRENCHES
3.10  CABLE PULLING AND INSTALLATION ASPECTS
3.11  CONTROL ROOM/AUXILIARY AREAS
4.  EARTHING AND BONDING
4.1  GENERAL
4.2  CONNECTIONS TO THE EARTHING SYSTEMS

4.3  EARTHING OF INTRINSICALLY SAFE CIRCUITRY

4.4  EARTHING OF CAVITY FLOORS
5.  LIGHTNING PROTECTION OF INSTRUMENTATION
5.1  GENERAL

5.2  INSTRUMENTATION AND CABLING IN THE FIELD
6.  PNEUMATIC TUBING

6.1  GENERAL
6.2  SELECTION AND SPECIFICATION OF TUBING

6.3  JUNCTION BOXES FOR MULTICORE TUBING

6.4  INSTALLATION
7.  IDENTIFICATION AND MARKING
7.1 CABLE IDENTIFICATIONS
7.2  IDENTIFICATION OF SYSTEM CABLES

7.3  IDENTIFICATION OF SINGLE CABLES/TUBING

7.4  IDENTIFICATION OF MULTICORES AND JUNCTION BOXES

7.5  MARKING
8.  REFERENCES
	APPENDIX 1 DISTANCE BETWEEN CABLE TRENCHES
		APPENDIX 2 ARRANGEMENT OF CABLE TRENCHES
		APPENDIX 3 TYPICAL EARTHING AT FAR/CCR
		APPENDIX 4 TYPICAL EARTHING OF INSTRUMENT SIGNAL CABLES IN THE FIELD
		APPENDIX 5 TYPICAL EARTHING OF INSTRUMENT SIGNAL CABLES IN THE MDF
                        
Document Text Contents
Page 1

PETRONAS TECHNICAL STANDARDS


DESIGN AND ENGINEERING PRACTICE













INSTRUMENT SIGNAL LINES













PTS 32.37.20.10
SEPTEMBER 2008





2010 PETROLIAM NASIONAL BERHAD (PETRONAS)
All rights reserved. No part of this document may be reproduced, stored in a retrieval system or transmitted in any form or by any means (electronic,

mechanical, photocopying, recording or otherwise) without the permission of the copyright owner

Page 2

PTS Circular

2009 - 001



This revision of PTS 32.37.20.10 - Instrument Signal Lines has been updated incorporating
PETRONAS Lessons Learnt, Best Practice and new information issued by relevant industry code
and standards. All updates in the document are highlighted in italic font.



The previous version of this PTS will be removed from PTS binder/ e-repository from herein
onwards.

Document Approval



Revision History
Date Version Description of Updates Author














PTS No: 32.37.20.10
Publication Title: Instrument Signal Lines
Base PTS Version: <Release 13>

Page 31

32.37.20.10
January 2009

Page 9
3. CABLE SEGREGATION, ROUTING AND INSTALLATION


3.1 INSTALLATION ASPECTS


Multi-core cables between junction boxes and control rooms shall be laid without splices.

Cables entering junction boxes, consoles, cross panels or the like, shall be fastened by means of
a cable gland, suitably sized and classified for the area of operation.

The design shall incorporate right of way and cable channeling for instrument and electrical signal
cables. Instrument signal cables, shall be separated at a distance of at least 0.3 m from electric
power cables when laid underground in cable trenches, or be on separate channels with metal
separation when laid above ground.

Routing of cables shall take account of any risk of damage or deterioration due to high
temperature lines, corrosive fluids, hydrocarbons or radiation (including UV radiation from direct
sunlight).

In any process-connected instrument where rupture of the sensing element may subject the
instrument case to process pressure and where the cable used has interstices which would permit
the migration of gas or liquid to a control room, a "Barrier Type" gland with sealing compound shall
be specified.

All cables for intrinsically-safe circuits must consist of groups of conductors twisted for each
independent circuit with screen and drain wires over the cable as a whole. The capacitance,
inductance and L/R ratio must not exceed values for intrinsically-safe circuits, depending on the
hazardous area classification and equipment parameters. Reference should be made to the
equipment hazardous area certification.



3.2 MOUNTING AND PROTECTION OF CABLES

The preferred method of cable protection is single-wire armouring for onshore and braided for
offshore, in accordance with the relevant. Conduit will not normally be approved, except for use
inside buildings in non-hazardous areas. All conduits shall be rigid steel, heavy wall, minimum 20
mm diameter, electro - galvanised, and shall be supported with appropriate straps, saddles or
hangers. See BS 31, BS 4568 and BS 4607 for conduit requirements. Unarmoured single-pair
thermocouple cable shall be protected by U-channel conduits or 1/2" galvanised pipe.

Where cables require support or protection from mechanical damage, they shall be run on
purpose-made proprietary ladder-rack, U-channel or cable tray, ladder-rack being specified for
widths of 300 mm or greater.

All components and accessories used with such proprietary systems should be of 316L SS
materials.

The appropriate proprietary fittings shall be specified for branch connections from tray or channel
to individual field instruments.

Cable support systems shall not be attached to process lines.


Design of the cable support system shall specify minimum clearance from any lines or equipment

where close proximity due to heat, chemicals or vibration may adversely affect the cables.

Supports for cable trays or cable ladders shall be suitable painted as per PTS 30.48.00.31 and
firmly fastened or welded.

Page 32

32.37.20.10
January 2009

Page 10
For underground or trench cables where there is extensive oil contamination in the soil or sand,
only then lead sheathed cables shall be used.

Horizontal cable trays shall be situated above air supply lines. Vertical cable trays shall be situated
behind or by the side of air supply lines unless space is limited by major equipment layout or
piping arrangements.

Cable trays shall be mounted in such a way as to allow access for maintenance or removal of
equipment without undue disturbance to the installation.

Cable trays and conduits shall be designed to be supported by steel structures or have their own
supports at every 2 meters lengths. Pipes for other services e.g. gas, steam, water etc. shall not
be used to support cable trays.

When a cable tray is designed for branching out, a flanged section shall be provided on the cable
tray leading to at each instrument. The tray shall be extended to the furthest instruments.

For cables lying in the cable channel, tray or underground trench, a marking strip (with tag no.) of
nylon-covered stainless steel or lead shall be fitted around the cable at every 5 meters length, at
both the starting and terminating points of the cable and at where the cable is fed into the control
room or auxiliary room. All marking strips for cables in cable channels shall be fastened by
stainless steel cable ties.

Cables entering junction boxes, consoles, cross panels or the like shall be designed to be
fastened by means of a cable clamp,

Instrument signal cables shall be designed to be situated at least 300 mm from electric power
cables shall be entirely clear of hot process lines.

Separate trays shall be used for l.S. and non I.S. cables as far as possible as per BS 5345.
Whenever this is a constraint, a barrier shall be provided for cable segregation.

Cable trays, conduits and cable ladders shall be galvanized iron or stainless steel.



3.3 CABLE SEGREGATION


The Cable Network shall be separated into:

System 1: High voltage systems (above 1000V).
System 2: Low voltage power supply and control cables for electrical systems (1000V and below)
System 3: Instrumentation and Telecommunication systems.

Where the cable support systems are installed horizontally one above the other, the cable network
shall be arranged from top to bottom, system 1, system 2 and system 3.

Cable ladders installed horizontally shall have sufficient space to facilitate cable pulling and
cleating/strapping.

Instrument and telecommunication cables shall be separated from low voltage power cables and
high voltage cables by minimum 300 mm.

Instrumentation and telecommunication cables may be routed on system 2 cable support systems
when the defined distance between the individual systems can be kept.

Page 61

32.37.20.10
January 2009

Appendix 4

APPENDIX 4 TYPICAL EARTHING OF INSTRUMENT SIGNAL CABLES IN THE FIELD

Page 62

32.37.20.10
January 2009

Appendix 5

APPENDIX 5 TYPICAL EARTHING OF INSTRUMENT SIGNAL CABLES IN THE MDF



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