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CSA C22.2 No. 244-19: Requirements for Enclosed and Dead-Front Switches
A comprehensive guide to the Canadian standard governing the safety, performance, and certification of enclosed switches used in electrical distribution systems
CSA C22.2 No. 244-19, published by the Canadian Standards Association (CSA), is the current edition of the standard for Enclosed and Dead-Front Switches used in electrical power distribution. It supersedes previous editions and harmonizes with the latest requirements of the Canadian Electrical Code (CE Code) and relevant North American practices. This article provides an in-depth look at the scope, key technical requirements, and compliance considerations for manufacturers, engineers, and inspectors working with these devices.
Scope and Purpose
CSA C22.2 No. 244-19 applies to enclosed switches, including disconnects, safety switches, and transfer switches rated up to 1000 V ac or 1500 V dc, intended for use in accordance with the CE Code. The standard covers both general-purpose enclosed switches and dead-front switches (where energized parts are not exposed when the switch is open). It also includes combination devices that incorporate fuses, circuit breakers, or other overcurrent protection. Excluded are switches intended for use in hazardous locations unless specifically designed and marked for such environments.
The purpose of the standard is to ensure uniform levels of safety with respect to fire, electric shock, and mechanical injury. It defines construction, performance, and marking requirements that permit certification under the CSA certification scheme.
Technical Requirements
The standard specifies a wide range of technical criteria that enclosed switches must meet. These are grouped into construction requirements, electrical ratings, and tests.
Construction and Materials
Enclosures must be constructed from rigid materials (metal, non-metallic, or combination) and provide the degree of protection specified by the manufacturer (e.g., NEMA/CSA Types 1, 3R, 4, 12). Dead-front switch designs must prevent accidental contact with live parts when the cover is open and the switch is in the OFF position. Current-carrying parts must be of suitable conductivity and corrosion resistance. Wire-bending space must comply with Table 1 based on the rating of the switch.
Ratings and Performance
Every switch must be marked with its rated voltage, continuous current, and short-circuit current rating (SCCR). The standard also requires ratings for withstand current and fault-closing capability where applicable. For switches with fusible elements, the maximum fuse rating must be marked. Temperature rise limits are specified for terminals and internal parts under continuous load.
| Switch Rating (A) | Minimum Bending Space (mm) | Wire Size Range (AWG/kcmil) |
|---|---|---|
| 30 | 25 | 14–8 |
| 60 | 32 | 14–6 |
| 100 | 38 | 14–1/0 |
| 200 | 50 | 14–250 |
| 400 | 65 | 14–400 |
| 600 | 75 | 14–600 |
| 800 | 90 | 14–800 |
| 1200 | 100 | 14–1000 |
Tests and Verification
Each type of switch must pass a series of routine and type tests, including:
- Dielectric voltage-withstand test at 1.25 × rated voltage + 1000 V (minimum 1500 V ac).
- Temperature-rise test at rated current with 100% load for switch bodies and terminals.
- Short-circuit current test to verify SCCR – for fusible switches this is done with the maximum fuse rating; for circuit-breaker switches with the highest-rated breaker.
- Endurance (mechanical and electrical) test – typically 6000 operations for general-use switches, 10 000 for switches marked for frequent use.
- Overload test – at 200% rated current for 50 operations.
Important: The short-circuit current rating (SCCR) of a combination switch is determined by the lowest rated component in the assembly. For fusible switches, the SCCR must be equal to or greater than the available fault current at the installation location. Always verify the SCCR marking before selecting a switch for a given application.
Implementation and Compliance Highlights
Manufacturers must ensure that production samples are certified by a recognized certification body (e.g., CSA, UL, TÜV) under the applicable Canadian requirements. The design and marking of switches must be identical to the certified prototype. Changes that affect safety or performance require recertification.
Compliance with CSA C22.2 No. 244-19 is mandatory for equipment installed under the Canadian Electrical Code. However, the standard does not cover all site-specific conditions; installers must follow the CE Code for proper installation, grounding, and bonding. Switches used in service entrance applications must meet additional CE Code rules (e.g., Section 6, Section 26).
Key points for achieving compliance include:
- Select enclosure type appropriate for the environment (e.g., Type 3R for outdoor, Type 4 for washdown).
- Ensure all contact points have adequate wire-bending space according to Table 1.
- Use properly rated conductors, terminals, and torque values per manufacturer instructions.
- Document all ratings clearly on the nameplate.
Tip: When specifying a switch for a motor branch circuit, ensure the switch is marked as suitable for motor disconnection and has an SCCR at least equal to the maximum motor locked-rotor current. Some switches are specifically listed for motor circuit use.
Compliance and Certification Notes
For a switch to be CSA certified, it must bear the CSA mark (monogram) or an equivalent accepted certification mark from a SCC-accredited agency. The certification indicates that representative samples have met the requirements of CSA C22.2 No. 244-19 and any applicable product-specific standards (e.g., for transfer switches, CSA C22.2 No. 178). Marking must include the manufacturer’s name or trademark, catalog number, electrical ratings, and the year of manufacture (or code).
Compliance strategy: Work with a certification body early in the design phase. Pre-certification screening for wire-bending space, temperature rise, and SCCR can prevent costly redesign. Use certified components (e.g., fuses, breakers, terminals) to streamline testing.
Common noncompliance issues: Incorrect wire-bending space for large conductors, inadequate SCCR for the available fault current, missing or illegible marking, and use of non-certified replacement parts that void the assembly certification.
Frequently Asked Questions
Q: Does CSA C22.2 No. 244-19 cover transfer switches?
A: Yes, it applies to enclosed transfer switches intended for use as a switching device, provided they are manually or electrically operated. Automatic transfer switches may also fall under this scope if they are basic enclosed switches, but often they require additional compliance with CSA C22.2 No. 178 (Transfer Switch Equipment). Manufacturers should verify the exact coverage of the standard for their specific product type.
A: Yes, it applies to enclosed transfer switches intended for use as a switching device, provided they are manually or electrically operated. Automatic transfer switches may also fall under this scope if they are basic enclosed switches, but often they require additional compliance with CSA C22.2 No. 178 (Transfer Switch Equipment). Manufacturers should verify the exact coverage of the standard for their specific product type.
Q: What is the difference between a “dead-front” switch and an “enclosed” switch?
A: Both terms refer to switches designed to prevent access to live parts under normal operation. A “dead-front” switch specifically means that no energized parts are exposed when the switch is in the open position (the front is “dead”). “Enclosed” is a broader term that includes any switch in an enclosure, which may allow some internal access if the door is opened. The standard applies to both types, but dead-front switches must meet additional construction requirements to ensure safety even when the enclosure is open (only de-energized parts are accessible).
A: Both terms refer to switches designed to prevent access to live parts under normal operation. A “dead-front” switch specifically means that no energized parts are exposed when the switch is in the open position (the front is “dead”). “Enclosed” is a broader term that includes any switch in an enclosure, which may allow some internal access if the door is opened. The standard applies to both types, but dead-front switches must meet additional construction requirements to ensure safety even when the enclosure is open (only de-energized parts are accessible).
Q: Can a switch certified to CSA C22.2 No. 244-19 be used in the United States?
A: CSA C22.2 No. 244-19 is a Canadian standard. For US installations, the equivalent standard is UL 98 (Enclosed and Dead-Front Switches). However, many switches are dual-listed (CSA and UL) and will meet both requirements. Consult the product marking; if it carries the CSA mark and the UL listing mark, it is generally acceptable in both countries under their respective codes.
A: CSA C22.2 No. 244-19 is a Canadian standard. For US installations, the equivalent standard is UL 98 (Enclosed and Dead-Front Switches). However, many switches are dual-listed (CSA and UL) and will meet both requirements. Consult the product marking; if it carries the CSA mark and the UL listing mark, it is generally acceptable in both countries under their respective codes.
Q: Are there any provisions for field-installed accessories?
A: The standard allows field installation of certain accessories (e.g., auxiliary contacts, key locks, interlocks) provided the modifications do not reduce the safety or rating of the switch. The manufacturer must specify permissible accessories in the installation manual. Field-installed components should be certified for use with the specific switch model to maintain the assembly’s overall certification.
A: The standard allows field installation of certain accessories (e.g., auxiliary contacts, key locks, interlocks) provided the modifications do not reduce the safety or rating of the switch. The manufacturer must specify permissible accessories in the installation manual. Field-installed components should be certified for use with the specific switch model to maintain the assembly’s overall certification.