CSA C68.10-14 (2015): Standard for Electric Power Cables with Extruded Insulation

Scope and Application

CSA C68.10-14 (2015) — officially titled Electric Power Cables with Extruded Insulation — provides comprehensive minimum requirements for the construction, materials, testing, and marking of single-core and multi-core cables intended for use in commercial, industrial, and utility electrical power systems. This standard applies to cables with rated voltages from 5 kV up to 35 kV, using thermoplastic or thermosetting (cross-linked) insulation systems, including cross-linked polyethylene (XLPE), ethylene propylene rubber (EPR), and other polymeric compounds.

The standard covers both metallic- and non-metallic-sheathed cables, shielded and unshielded configurations, and includes provisions for conductors with annealed copper or aluminum. It serves as a companion document to the Canadian Electrical Code (CE Code) for installations requiring routine compliance. Reaffirmed in 2015, this edition maintains earlier technical requirements while clarifying testing procedures and adding guidance for new insulating materials.

Technical Requirements

Conductor and Insulation Materials

Conductors must be stranded annealed copper or aluminum, complying with CSA standards for conductor size and conductivity. Insulation materials are required to pass stringent physical and electrical tests:

• XLPE: Thermosetting polyethylene with temperature rating of 90 °C normal operation, 130 °C emergency overload, and 250 °C short-circuit rating.
• EPR: Ethylene propylene rubber insulation rated at 105 °C normal operation, 140 °C emergency, and 260 °C short-circuit.
• Thermoplastic (PVC): Limited to 75 °C normal for dry locations, subject to additional ageing tests.

Insulation thickness varies with voltage class and conductor size. Table 1 presents typical values for medium-voltage cables.

Test Requirements

Cables manufactured to CSA C68.10-14 must undergo a series of type and routine tests. Key tests include:

• Partial discharge (PD) test: All cables rated 5 kV and above are tested for partial discharge level not exceeding 5 pC at 1.5 × rated voltage.
• Withstand voltage test: A high-voltage AC test at 3 × rated voltage (or DC equivalent) is applied for 5 minutes on production lengths.
• Bend test: Samples of completed cable must pass a bending cycle around a mandrel of 12–20 times the cable diameter without insulation cracking.
• Insulation resistance test: Minimum 2000 MΩ·km at 500 V DC for cables with up to 35 kV rating.
• Flame propagation test: Cables designated as “FT” (flame retardant) must meet CSA C22.2 No. 2556 vertical tray flame test requirements.

Implementation Highlights

Manufacturing Impact

Adoption of CSA C68.10-14 influences extrusion parameters, cooling profiles, and quality assurance processes. Manufacturers must maintain precise control of insulation thickness and ensure concentricity within ±5% of nominal wall thickness. Changes to compound formulations require re-qualification through partial discharge and ageing tests.

Cable designs may utilize a metallic shield (copper tape or wire) and an overall jacket (PVC, polyethylene, or low-smoke zero-halogen material). For shielded cables, the metal shield must be capable of withstanding fault currents up to 10 kA rms for 1 second, verified by a short-circuit test.

Marking and Identification

Each cable must be durably marked on the jacket or outer sheath at intervals not exceeding 600 mm with:

• Manufacturer’s name or trademark.
• Standard designation CSA C68.10-14.
• Voltage rating (e.g., 15 kV).
• Conductor material (CU or AL).
• Number of cores and size (e.g., 3 C 1/0 AWG).
• Year of manufacture.
• Flame test rating (e.g., FT1, FT4, FT6) if applicable.

Compliance and Testing Notes

Compliance with CSA C68.10-14 is typically verified through a combination of:

• Factory acceptance testing (FAT): Performed on every cable length by the manufacturer.
• Witnessing by accredited bodies: Routine and type tests may be witnessed by CSA Group or other recognized certification agencies.
• Field testing: After installation, cables should be subjected to an insulation resistance test and, where permitted, a DC high-potential test at 80% of the factory test voltage per CE Code requirements.

The standard also gives guidance for test methods and acceptance criteria. Any departure from specified limits requires a documented engineering justification and, if applicable, a deviation permit from the authority having jurisdiction.

Review of CSA C68.10-14 (2015) — Revision published in 2026.