Cable Schedule is a document containing list of instrument cable. This document shows cable as well as gland required by each instrument or connection.
The information of the cable schedule shall consists:
- Cable Number
- Cable Type / Specification
- Cable Size
- Cable Length
- Source and destination termination description
- Cable gland type and size for each incoming cable
Reference document: Instrument Index / I/O List
Reference drawing: Instrument Cable Layout, Interconnection block diagram
Filter tag numbers that has a wire from instrument index.
I/O list will cover most of the tag number, because it only show instrument tag number which has I/O and therefore require wires.
Please note that instrument which is not loop powered requires additional cable for power.
Instrument cable layout and interconnection block diagram will make the preparation of cable schedule more convenience in specifying cable source and destination.
The purpose of Cable Schedule
Cable schedule is a reference in preparing Material Take-Off of cable for procurement. However, cable length shown on this document are approximate only. Therefore, there should be contingency for material procurement to allow spare for cable cutting, unexpected barrier in the field, riser, etc.
Cable schedule will be referred also during construction phase, however it is not recommended to cut the cable based on the length information stated on the cable schedule. For actual cutting during installation, the common practice is to pull the cable from its drum and cut in the field.