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CSA C22.2 No. 107.3-14 (2017): Safety Requirements for Uninterruptible Power Systems
A comprehensive guide to the scope, technical requirements, and compliance for UPS certification under the Canadian Electrical Code
CSA C22.2 No. 107.3-14 (2017) is a key safety standard within the Canadian Electrical Code Part II series, governing the design, construction, and testing of uninterruptible power systems (UPS) intended for installation in non-hazardous locations. This standard harmonizes with international benchmarks such as IEC 62040-1 and UL 1778 while incorporating specific Canadian requirements for grounding, marking, and environmental conditions. Compliance with CSA C22.2 No. 107.3-14 is mandatory for manufacturers seeking to place UPS equipment on the Canadian market with a recognized certification mark.
Scope of the Standard
CSA C22.2 No. 107.3-14 applies to stationary and portable UPS units that incorporate an energy storage device (e.g., batteries, flywheels, or supercapacitors) and provide regulated AC power to critical loads. The standard covers:
- UPS with rated AC input/output voltages up to 600 V and DC input voltages up to 1000 V;
- Systems intended for use in dry, indoor locations in accordance with CSA C22.1 (CEC Part I);
- Equipment employing static conversion technology (online, offline, line-interactive);
- Battery systems and their charging/protection circuits integral to the UPS.
The standard does not apply to rotating UPS (motor-generator sets), UPS intended for medical life-support systems unless specifically designed to meet additional requirements, or systems for hazardous locations (e.g., Class I Division 1).
Key Technical Requirements
Construction and Marking
All UPS must be constructed using components rated for the intended electrical and thermal stresses. Marking must be in both English and French, and include rated voltage, current, power (kVA/kW), output voltage regulation, and caution statements for battery handling and electric shock. The manufacturer must specify the maximum ambient operating temperature (typically 40 °C).
Protection Against Electric Shock
Accessible parts must be reliably bonded to ground. Creepage and clearance distances follow the requirements of CSA C22.2 No. 0. For primary circuits, the minimum clearance must comply with Table 2 of the standard. A simple dielectric strength test is required for production-line verification:
| Circuit Pair | Test Voltage (V) | Duration (s) | Minimum IR (MΩ) |
|---|---|---|---|
| Primary to ground | 1000 + 2×Un, min 1500 | 60 | 2 |
| Primary to secondary | 1000 + 2×Un, min 1500 | 60 | 2 |
| Secondary to accessible conductive parts | 1000 + 2×Un, min 1500 | 60 | 2 |
Battery Systems
Battery compartments must be designed to prevent excessive temperature and allow adequate ventilation to avoid accumulation of explosive gases (for vented lead-acid types). Charging circuits must limit the charging current and voltage to the manufacturer’s specifications, and automatic disconnection on overcurrent or overtemperature is required. The standard also addresses protection against short circuits and reverse polarity.
Abnormal Operation and Fault Conditions
A UPS must not pose a fire or shock hazard under single-fault conditions. The standard mandates testing under:
- Overload (up to 150 % of rated load);
- Short circuit on output;
- Battery overcharge or deep discharge;
- Failure of cooling fans;
- Component blockage (e.g., relay armature).
Compliance advantage: Manufacturers who integrate thermal fuses, fuses with proper interrupt ratings, and self-monitoring circuits typically achieve smoother certification results.
Tip: Always use components that are CSA or UL recognized to reduce the need for additional component-level tests. Check battery cells for compliance with CSA C22.2 No. 166 or UL 1989.
Implementation and Design Considerations
Designing a UPS to meet CSA C22.2 No. 107.3-14 involves careful attention to the following areas:
- Insulation coordination: Creepage and clearance distances for printed circuit boards, transformer windings, and semiconductor heat sinks must meet the pollution degree (typically 2) and overvoltage category (OVC II or III).
- Grounding: The bonding conductor must be sized per CEC Part I and the impedance kept low enough to ensure protective device operation. Ground fault detection may be required for upstream leakage current > 10 mA.
- Thermal management: Battery groups must be separated from heat-generating power components. Verification tests include a temperature rise test at rated load until stability is reached, typically with thermocouples at key junctions.
- Electromagnetic compatibility (EMC): While not part of C22.2 No. 107.3-14, simultaneous compliance with ICES-001 or ICES-003 may be required by Innovation, Science and Economic Development Canada (ISED).
Warning: Batteries in UPS can produce hydrogen during charging. Ensure the ventilation design prevents gas accumulation above 1 % volume in air. Use spark-proof or remote-vented battery cabinets for sealed units with high charge rates.
Danger: Incorrect or missing grounding of the UPS chassis can result in a shock hazard. Always verify that the bonding path from the input ground to all accessible metallic parts has a resistance of ≤ 0.1 Ω during the continuity test.
Compliance and Certification
Product certification in Canada is typically handled by accredited organizations such as CSA Group, UL (cUL), or Intertek (cETL). The process includes the following steps:
- Submission of design documentation, including schematics, bill of materials, and drawings;
- Witnessed testing in the laboratory for all clauses of the standard (dielectric, temperature rise, abnormal conditions, endurance, etc.);
- Factory inspection to confirm quality control procedures and traceability of critical components;
- Issuance of a certificate and permission to apply the certification mark.
Once certified, the manufacturer must retain a compliance file and report any significant design changes to the certifier. Marking must include the certification mark, rated parameters (V, A, kVA, kW), and caution statements in English and French.
Frequently Asked Questions
Q: What types of UPS are covered by CSA C22.2 No. 107.3-14?
A: The standard covers all static UPS that include an energy storage element, whether line-interactive, offline (standby), or online (double-conversion), with input/output voltages up to 600 V AC and DC input up to 1000 V. It does not cover rotary UPS or systems for hazardous locations.
A: The standard covers all static UPS that include an energy storage element, whether line-interactive, offline (standby), or online (double-conversion), with input/output voltages up to 600 V AC and DC input up to 1000 V. It does not cover rotary UPS or systems for hazardous locations.
Q: Is compliance with CSA C22.2 No. 107.3-14 mandatory in Canada?
A: Yes. Most provinces and territories adopt the Canadian Electrical Code Part I, which requires electrical products to be certified to the relevant CSA standard by an accredited certification body. A UPS sold in Canada must bear a recognized mark (CSA, cUL, or cETL) to demonstrate compliance.
A: Yes. Most provinces and territories adopt the Canadian Electrical Code Part I, which requires electrical products to be certified to the relevant CSA standard by an accredited certification body. A UPS sold in Canada must bear a recognized mark (CSA, cUL, or cETL) to demonstrate compliance.
Q: How does CSA C22.2 No. 107.3-14 differ from UL 1778?
A: The two standards are largely harmonized in content. However, CSA C22.2 No. 107.3-14 includes specific references to the Canadian Electrical Code (CEC Part I), bilingual marking requirements (English and French), and sometimes stricter grounding or bonding provisions. In practice, manufacturers may choose to certify to both standards simultaneously for cross-border marketing.
A: The two standards are largely harmonized in content. However, CSA C22.2 No. 107.3-14 includes specific references to the Canadian Electrical Code (CEC Part I), bilingual marking requirements (English and French), and sometimes stricter grounding or bonding provisions. In practice, manufacturers may choose to certify to both standards simultaneously for cross-border marketing.
Q: What are the most common reasons for failure during certification testing?
A: Frequent issues include: insufficient clearance/creepage, excessive temperature rise under rated load, inadequate battery protection (lack of overcharge cutoff), and failure to meet dielectric withstand after humidity conditioning. Proper design reviews using the standard’s test parameters help minimize these failures.
A: Frequent issues include: insufficient clearance/creepage, excessive temperature rise under rated load, inadequate battery protection (lack of overcharge cutoff), and failure to meet dielectric withstand after humidity conditioning. Proper design reviews using the standard’s test parameters help minimize these failures.
Last updated: 2026