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CSA C22.2 No. 130-16 (2019): Comprehensive Guide to Bushings for Use in Electrical Equipment
Understanding the Scope, Technical Requirements, and Compliance Pathways for Canadian Electrical Bushing Standards
Scope and Application
CSA C22.2 No. 130-16 (2019) applies to bushings for use in electrical equipment rated up to 25 kV, designed for installations in accordance with the Canadian Electrical Code, Part I. The standard covers bushings used in transformers, switchgear, motors, generators, and similar apparatus where a conductor passes through a grounded partition. It addresses both indoor and outdoor applications, including bushings intended for use in hazardous locations when combined with other applicable standards.
The standard defines requirements for construction, electrical and thermal performance, dielectric strength, mechanical integrity, and environmental durability. It does not apply to bushings integrated into sealed, factory-assembled devices unless specifically invoked by the product standard. The edition number “130-16” indicates the sixteenth edition, updated and reaffirmed in 2019 to align with current industry practices and harmonization efforts with U.S. and international standards.
Technical Requirements
Electrical Ratings and Dielectric Performance
Bushings must withstand specified voltage levels under normal and abnormal conditions. The standard prescribes dielectric tests including power-frequency withstand voltage, lightning impulse withstand voltage, and partial discharge measurements. Table 1 summarizes the typical test voltage levels based on the rated voltage of the bushing.
| Rated Voltage (kV) | Power-Frequency Withstand Voltage (kV, rms) | Lightning Impulse Withstand Voltage (kV, peak) | Minimum Creepage Distance (mm) |
|---|---|---|---|
| 1.2 | 3.0 | 10 | 16 |
| 2.5 | 5.0 | 20 | 25 |
| 5.0 | 10.0 | 40 | 45 |
| 8.7 | 17.5 | 75 | 65 |
| 15.0 | 27.0 | 95 | 90 |
| 25.0 | 40.0 | 125 | 130 |
Tip: When selecting creepage distances, consider pollution severity levels as defined in the product standard. Additional clearance may be required for outdoor installations.
Material and Construction
Bushings must be constructed from materials that resist tracking, moisture absorption, and thermal degradation. The standard specifies minimum requirements for:
- Insulating material: Porcelain, glass-fiber-reinforced epoxy, or thermosetting compounds with a comparative tracking index (CTI) ≥ 175 V.
- Conductors: Copper or aluminum with adequate cross-sectional area for rated current and short-circuit conditions.
- Sealing: Gaskets or encapsulation that prevent moisture ingress and maintain a gas-tight seal for oil- or gas-filled apparatus.
Thermal and Mechanical Tests
Bushings are subjected to temperature-rise tests at rated current to ensure that hot-spot temperatures do not exceed the insulation class limits. Mechanical tests include cantilever load, torque at terminals, and hydrostatic pressure tests for oil-filled bushings. The standard also mandates a thermal-shock test for bushings rated above 5 kV.
Warning: Inadequate sealing can lead to partial discharge and eventual failure. Always verify manufacturer’s torque values for mounting and terminal connections.
Implementation Highlights
Design Considerations for Original Equipment Manufacturers (OEMs)
OEMs integrating bushings into equipment must ensure that the bushing’s rated voltage, current, and short-circuit ratings match the system parameters. The standard allows for optional marking of the bushing with the maximum equipment voltage to prevent misapplication.
Installation must follow the bushing manufacturer’s instructions, particularly for tightening torque and orientation. For bushings intended for use in enclosures, the clearance to grounded parts must be maintained per Table 2 (not shown) or as specified in the equipment standard. The use of proper anti-rotation features and flexible connectors is recommended to reduce mechanical stress.
Good Practice: Dual-certified CSA/UL bushings simplify compliance for manufacturers exporting to Canada and the United States. Many CSA C22.2 No. 130-16 requirements are harmonized with UL 486E and ANSI C29-series.
Compliance Notes
Certification and Marking
Bushings covered by this standard are typically required to be certified by an accredited certification body (e.g., CSA Group, UL, SGS) for recognition by Canadian regulatory authorities. Certification involves type testing, factory inspection, and follow-up audits. The certification mark must be permanently affixed to each bushing and must include the standard number (CSA C22.2 No. 130-16) and the rated voltage and current.
Markets and Acceptance
While predominantly used in Canada, bushings complying with CSA C22.2 No. 130-16 are accepted in other jurisdictions that recognize CSA standards or that require equivalent performance. For projects under the Canadian Electrical Code, provincial inspectors will require evidence of compliance (e.g., certificate of compliance or field evaluation).
Non-Compliance Risk: Using uncertified bushings in installations governed by the Canadian Electrical Code may result in rejection by the authority having jurisdiction (AHJ), production delays, and liability exposure. Always verify valid certification marks.
Updates and Reaffirmation
The 2019 reaffirmation confirmed no technical changes, but the standard continues to be reviewed. Manufacturers should monitor CSA Group announcements for amendments that may introduce new requirements such as enhanced partial discharge limits or recycling directives. The current edition remains in effect until superseded.
Frequently Asked Questions
Q: What types of bushings are covered by CSA C22.2 No. 130-16?
A: The standard covers all types of bushings used in electrical equipment, including cable bushings, transformer bushings, feed-through bushings, and mounting bushings, rated up to 25 kV.
A: The standard covers all types of bushings used in electrical equipment, including cable bushings, transformer bushings, feed-through bushings, and mounting bushings, rated up to 25 kV.
Q: Is compliance with this standard mandatory in Canada?
A: Yes, relevant provincial safety codes require bushings to be certified to the applicable CSA C22.2 standard. CSA C22.2 No. 130-16 is referenced by the Canadian Electrical Code.
A: Yes, relevant provincial safety codes require bushings to be certified to the applicable CSA C22.2 standard. CSA C22.2 No. 130-16 is referenced by the Canadian Electrical Code.
Q: Can a bushing be certified to both CSA C22.2 No. 130-16 and UL 486E?
A: Yes, many manufacturers obtain dual certification to serve both the Canadian and U.S. markets. The certification body will assess the product against each standard’s requirements.
A: Yes, many manufacturers obtain dual certification to serve both the Canadian and U.S. markets. The certification body will assess the product against each standard’s requirements.
Q: How often is the standard revised?
A: CSA standards are reviewed every five years. The next review cycle for No. 130-16 is expected to begin in 2024–2025, with possible publication of a new edition in 2026 or later.
A: CSA standards are reviewed every five years. The next review cycle for No. 130-16 is expected to begin in 2024–2025, with possible publication of a new edition in 2026 or later.
Technical article copyright © 2026. All information is for general guidance and should be verified against the official standard.