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CSA C22.2 No. 290-19: Surge Protective Devices – Technical Requirements and Compliance
An in-depth look at the Canadian standard for SPDs, covering scope, performance criteria, and certification requirements
Surge protective devices (SPDs) are essential components in modern electrical installations, safeguarding sensitive equipment from transient overvoltages caused by lightning, switching operations, or grid disturbances. In Canada, the design, testing, and certification of SPDs are governed by CSA C22.2 No. 290-19, the national standard harmonized with UL 1449 4th Edition. This article provides a comprehensive overview of the standard’s scope, technical requirements, implementation highlights, and compliance notes for manufacturers and electrical engineers.
1. Scope of CSA C22.2 No. 290-19
CSA C22.2 No. 290-19 applies to surge protective devices intended for permanent connection to ac power circuits rated up to 1000 V (root-mean-square) or dc power circuits rated up to 1500 V. It covers SPDs designed for indoor or outdoor use, both for installation at the service entrance (Type 1), on load side of the service disconnect (Type 2), and at the point of utilization (Type 3). The standard also addresses component assemblies (Type 4) that are intended for use within equipment.
Notably, the standard excludes low-voltage surge arresters covered by CSA C22.2 No. 273 (similar to IEEE C62.11) and devices used in telecommunications, signaling, or data circuits, which fall under other standards such as CSA TIA-968 or CAN/CSA-C22.2 No. 62368-1.
Key Definitions
- Voltage Protection Rating (VPR) – The limiting voltage measured during specific surge tests.
- Nominal Discharge Current (Iₙ) – The peak value of the current waveform (usually 8/20 µs) used for classification and endurance testing.
- Maximum Continuous Operating Voltage (MCOV) – The maximum rms or dc voltage that can be applied continuously.
- Short-Circuit Current Rating (SCCR) – The maximum prospective short-circuit current the SPD can withstand without failure.
2. Technical Requirements and Performance Criteria
The standard prescribes rigorous test protocols to ensure SPDs provide reliable protection under various surge conditions. Key performance parameters include:
2.1 Surge Current Handling
SPDs must withstand a defined number of surge impulses without degradation. Tests include the nominal discharge current (Iₙ) test at 8/20 µs waveform and, for Type 1 and Type 2 devices, a high-current test (Iₙₘₐₓ) using the combination wave (1.2/50 µs voltage and 8/20 µs current). Endurance is verified through multiple surge applications.
2.2 Voltage Protection Ratio (VPR) and Limiting Voltage
The VPR is measured using two methods: the limiting voltage test at Iₙ and the combination wave test. The measured values must not exceed the rated VPR listed by the manufacturer. Maximum values are generally limited by the standard according to system voltage (e.g., for 120/240 V single-phase systems, typical VPR values range from 600 V to 2400 V depending on SPD type and application).
| Parameter | Type 1 | Type 2 | Type 3 |
|---|---|---|---|
| Nominal Voltage (ac, 50/60 Hz) | 120 – 600 V | 120 – 600 V | 120 – 240 V |
| Iₙ (8/20 µs) Rating | ≥ 10 kA | ≥ 5 kA | ≥ 3 kA |
| Iₘₐₓ (maximum surge current) | ≥ 20 kA | ≥ 10 kA | Not required |
| VPR (for 120/240 V systems) | ≤ 1200 V | ≤ 1200 V | ≤ 600 V |
| SCCR | ≥ 65 kA (service entrance) | ≥ 50 kA | ≥ 10 kA |
2.3 Additional Tests
- Dielectric voltage-withstand test – Verifies insulation integrity at 1000 V rms plus twice the MCOV.
- Abnormal overvoltage and temporary overvoltage (TOV) test – Simulates grid faults and verifies safe operation even under line-to-ground overvoltage.
- Thermal runaway / thermal protection test – Ensures that components disconnect safely if the varistor or suppressor overheats.
3. Implementation Considerations for Manufacturers
Designing SPDs to meet CSA C22.2 No. 290-19 requires careful selection of components (MOVs, GDTs, arrestors) and robust assembly. The standard mandates product certification by an accredited organization (e.g., CSA Group, UL, Intertek). Key implementation aspects include:
3.1 Marking and Documentation
Each SPD must be permanently marked with:
- Manufacturer’s name or trademark
- Model/type designation
- Rated voltage and frequency
- MCOV
- VPR for each mode
- Iₙ or Iₘₐₓ (as applicable)
- SCCR
- Type (1, 2, or 3)
- Wiring diagram (for Field-Wired SPDs)
Installation instructions must include torque values for terminal connections, environmental limits (temperature range, enclosure rating), and guidance on SPD coordination with overcurrent protection.
3.2 Production Line Testing
While design verification tests (DVT) are executed on prototype samples, some production line tests are required by the standard, such as:
- Continuity and bond test
- Dielectric strength (hi-pot) test
- Operating voltage check
4. Compliance and Certification Notes
CSA C22.2 No. 290-19 is harmonized with UL 1449 4th Ed., but Canadian-specific deviations exist. Manufacturers seeking the CSA mark must account for:
- Nominal voltage ratings: The standard includes rated system voltages common in Canada, such as 347/600 V and 600 V three-phase.
- Hydraulic magnetic breaker coordination: In Canada, SPDs are often paired with specific breakers; the standard clarifies the need for evaluation as a system.
- Environmental conditions: SPDs intended for outdoor use must be tested to Canadian ambient temperature extremes (−40 °C to +50 °C).
Certification to CSA C22.2 No. 290-19 is typically part of a broader product listing that also checks compliance with the Canadian Electrical Code (CE Code) requirements. Retesting is required if the design changes or if the SPD is to be paired with a different overcurrent protection device (OCPD).
4.1 Where to Obtain the Standard
The official document can be purchased from the CSA Group online store. For interpretive guidance, manufacturers are encouraged to contact the CSA certification team directly or consult with recognized third-party testing laboratories.
In summary, CSA C22.2 No. 290-19 provides a robust framework for ensuring the safety and performance of surge protective devices in Canadian electrical installations. Adherence to its rigorous testing and marking requirements is essential for market access and for delivering reliable surge protection to end users.
Frequently Asked Questions
Q: What is the difference between CSA C22.2 No. 290-19 and UL 1449 4th Edition?
A: The standards are largely harmonized in terms of test methods and performance metrics. However, CSA C22.2 No. 290-19 includes additional Canadian configurations (e.g., 347/600 V systems) and references the Canadian Electrical Code. Marking and documentation details also reflect Canadian requirements. Manufacturers submitting for CSA certification may need to provide additional test data for the Canadian voltage and environmental extremes.
A: The standards are largely harmonized in terms of test methods and performance metrics. However, CSA C22.2 No. 290-19 includes additional Canadian configurations (e.g., 347/600 V systems) and references the Canadian Electrical Code. Marking and documentation details also reflect Canadian requirements. Manufacturers submitting for CSA certification may need to provide additional test data for the Canadian voltage and environmental extremes.
Q: Does CSA C22.2 No. 290-19 cover SPDs for DC applications?
A: Yes, the standard applies to SPDs intended for DC power circuits up to 1500 V. This includes photovoltaic (PV) systems and battery storage installations. The same type classification (1, 2, 3) applies, but additional DC-specific requirements (such as polarity marking and reverse current protection) are included.
A: Yes, the standard applies to SPDs intended for DC power circuits up to 1500 V. This includes photovoltaic (PV) systems and battery storage installations. The same type classification (1, 2, 3) applies, but additional DC-specific requirements (such as polarity marking and reverse current protection) are included.
Q: What are the marking requirements for SPDs under this standard?
A: In addition to general markings (manufacturer, model, rating), the SPD must clearly display the type (1, 2, or 3), the voltage protection rating (VPR) for each protection mode, the nominal discharge current (Iₙ) and maximum surge current (Iₘₐₓ) as applicable, and the short-circuit current rating (SCCR). The marking must be permanent, legible, and located on the device itself or on the smallest shipping container if the device is too small.
A: In addition to general markings (manufacturer, model, rating), the SPD must clearly display the type (1, 2, or 3), the voltage protection rating (VPR) for each protection mode, the nominal discharge current (Iₙ) and maximum surge current (Iₘₐₓ) as applicable, and the short-circuit current rating (SCCR). The marking must be permanent, legible, and located on the device itself or on the smallest shipping container if the device is too small.
Q: Is third-party certification mandatory in Canada?
A: While CSA C22.2 No. 290-19 is a voluntary standard, certification to an accredited body is effectively mandatory because electrical authorities in all provinces and territories require SPDs to be listed/labeled to the applicable CSA standard as a condition of installation. The certification mark from CSA Group, UL, or other recognized SCC-accredited organization serves as proof of compliance.
A: While CSA C22.2 No. 290-19 is a voluntary standard, certification to an accredited body is effectively mandatory because electrical authorities in all provinces and territories require SPDs to be listed/labeled to the applicable CSA standard as a condition of installation. The certification mark from CSA Group, UL, or other recognized SCC-accredited organization serves as proof of compliance.
This technical article is based on the 2019 edition of CSA C22.2 No. 290 and is intended for informational purposes. For official compliance, refer to the latest published standard. — 2026