Section 12 — Instruments and Controls

Instrument Cable

IPE Engineering Practice IPE-EP-12-1-25

Document number: IPE-EP-12-1-25 · Section: 12 — Instruments and Controls

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SCOPE

This Practice details the requirements of 300 volt single pair and multiple–pair thermocouple and instrument cable.

Any deviation from this Practice must be approved by the procedure described in EP 1–1–3. A revision bar indicates all changes made to this Revision.

REFERENCES

The following codes and standards shall be considered as part of this Practice. All documents shall be the latest editions in force on the date of issuance of this Practice.

STANDARDS AND PUBLICATIONS

IPE Engineering Practices
EP 1–1–3 Deviations to IPE Engineering Practices
ANSI
ANSI/MC 96.1 Temperature Measurement Thermocouples
IEEE
383 IEEE Standard for Type Test of Class IE Electric Cables, Field Splices, and Connections for Nuclear Power Generating Stations
UL
Subject 13

DEFINITIONS

Contractor - Company or business that agrees to furnish materials or perform specified services at a specified price and/or rate to the Owner.

Inspector - A Inflection Point Engineering, LLC appointed engineer or inspector.

Manufacturer - The recipient of a direct or indirect purchase order for materials and/or equipment. In this context, a direct order is one issued to a manufacturer by a contractor or the Owner. An indirect order is one issued to a manufacturer by a vendor (recipient of a direct order) for materials, fabricated components, or subassemblies.

Owner - Inflection Point Engineering, LLC.

Owner’s Engineer - A Inflection Point Engineering, LLC appointed engineer.

Purchaser - The party placing a direct purchase order. The purchaser is the Owner’s designated representative.

GENERAL

All instrument cable shall be UL listed as 300 volt power limited tray cable as a minimum. It shall be listed for use in Class 1, Group B, D, Division 2 Hazardous Areas. The insulation shall have a minimum temperature rating of 105oC and minimum nominal thickness of 15 mils per UL Subject 13.
The jacket of multiple pair/triad cables shall be flame resistant and pass IEEE 383 flame test. Jacket shall be sunlight and oil resistant.
A rip cord shall be laid longitudinally under the jacket to facilitate jacket removal without damage to the pairs/triads.
Multi–pair construction shall be individual shielded pair with an overall shield.
Water tight seals shall be applied to both ends of the cable to protect cable ends and to prevent entrance of moisture during transit and out–of–doors storage.
Cable shall be placed on non-returnable reels with both ends readily accessible for on–the–reel set–up and field testing.

INSTRUMENT CABLE SINGLE PAIR/TRIAD CONSTRUCTION

The conductor shall be bare soft annealed copper #16 AWG minimum, Class B, 7-strand concentric, per ASTM B-8.
Each pair or triad shall be twisted together with one seven-strand tinned copper drain wire. Drain wire shall be no less than #22 AWG. The lay shall not exceed 2.5” for pairs or 3.5” for triads.
An aluminum/polyester tape shall be wrapped around each pair or triad with an overlap to ensure 100% shielding.
A black, flame–retardant PVC jacket shall be over the shielded assembly. The jacket shall have an average of thickness of 35 mils.

INSTRUMENT CABLE MULTI-PAIR CONSTRUCTION

The conductor shall be bare soft annealed copper #20 AWG minimum, Class B, 7-strand concentric, per ASTM B-8.
Each pair or triad shall be twisted together with one 7-strand tinned copper drain wire. Drain wire shall be no less than #22 AWG. The lay shall not exceed 2.5” for pairs or 3.5” for triads.
An aluminum/polyester tape shall be wrapped around each pair or triad with an overlap to ensure 100% shielding.
A #22 AWG, bare copper conductor, shall be provided has a communication wire.
An aluminum/polyester tape shall be applied over the assembled core with an overlap to ensure 100% shielding.
A 7 strand tinned copper drain wire, the same size as the conductor, shall be applied over the aluminum/polyester shield.

A black, flame–retardant PVC jacket shall be over the shielded assembly. The jacket thickness shall be 50 mils for 4 and 8 pair, 60 mils for 10, 12, 16 and 20 pair, and 70 mils for 24 and 36 pair cables.

THERMOCOUPLE EXTENSION CABLES SINGLE PAIR CONSTRUCTION

The conductor shall be solid allow, #16 AWG minimum, per ANSI/MC96.1.
Each pair shall be twisted together with one seven–strand tinned copper drain wire. Drain wire shall be no less than #22 AWG. The lay shall not exceed 2.5”.
An aluminum/polyester tape shall be wrapped around each pair with an overlap to ensure 100% shielding.
A ANSI C96.1 color, flame–retardant PVC jacket shall be over the shielded assembly. The jacket shall have an average of thickness of 35 mils.

THERMOCOUPLE EXTENSION CABLE MULTI-PAIR CONSTRUCTION

The conductor shall be solid allow, #20 AWG minimum, per ANSI/MC96.1.
Each pair shall be twisted together with one 7-strand tinned copper drain wire. Drain wire shall be no less than #22 AWG. The lay shall not exceed 2.5”.
An aluminum/polyester tape shall be wrapped around each pair with an overlap to ensure 100% shielding.
A #22 AWG, bare copper conductor, shall be provided has a communication wire.
An aluminum/polyester tape shall be applied over the assembled core with an overlap to ensure 100% shielding.
A 7 strand tinned copper drain wire, the same size as the conductor, shall be applied over the aluminum/polyester shield.
A ANSI C96.1 color, flame–retardant PVC jacket shall be over the shielded assembly. The jacket thickness shall be 50 mils for 4 and 8 pair, 60 mils for 10, 12, 16, 20, and 24 pair, and 70 mils for 36 pair cables.

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