Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
CAN CSA C50052-99 (2016): Low-Voltage Fuse-Links for Industrial Applications – Technical Requirements and Compliance
A comprehensive overview of the Canadian adoption of IEC 60269-2 for industrial fuse-links, covering rated voltages, breaking capacities, and testing requirements
Scope of CAN CSA C50052-99 (2016)
CAN CSA C50052-99 (2016) is the Canadian adoption of IEC 60269-2, specifically addressing low-voltage fuse-links intended for use by authorized persons in industrial installations. The standard defines supplementary requirements for fuse-links rated up to 1000 V AC or 1500 V DC, covering dimensions, electrical characteristics, and performance criteria. It applies to fuse-links primarily used in circuits supplied by transformers, switchgear, and motor control centers where high fault currents may occur.
Note: This standard is reaffirmed in 2016 and remains the governing document for industrial fuse-links in Canada, superseding earlier editions and aligning with international practice.
Technical Requirements
Rated Voltage and Breaking Capacity
The standard establishes preferred rated voltage values (e.g., 250 V, 500 V, 690 V AC) and requires that fuse-links withstand and interrupt specified overcurrents. Breaking capacity is classified as AC 50 kA or higher, depending on the rated voltage. For DC applications, the standard requires testing at a time constant of 15 ms to 20 ms to simulate real-world inductive loads.
| Parameter | Requirement |
|---|---|
| Rated voltage (AC) | 250 V, 400 V, 500 V, 690 V |
| Rated voltage (DC) | 250 V, 440 V, 1000 V |
| Breaking capacity (AC) | ≥ 50 kA (at 690 V) |
| Breaking capacity (DC) | ≥ 30 kA (at 1000 V) |
| Power dissipation | Per manufacturer’s data, verified by test |
| Overload capability | 1.25 × rated current for 1 h |
Temperature Rise and Power Dissipation
Fuse-links must not exceed a temperature rise of 75 °C above ambient during rated current flow at rated voltage. The standard specifies measurement points on the fuse-link contacts and body. Power dissipation values are declared by the manufacturer and must be verified by a type test using calorimetric methods or equivalent.
Design Tip: When integrating fuse-links into switchgear, ensure sufficient ventilation and contact pressure to maintain temperature rise within limits, as exceeding 75 °C may degrade insulation materials.
Dimensions and Interchangeability
CAN CSA C50052-99 (2016) prescribes mechanical dimensions for blade, cartridge, and bolted-link configurations to ensure interchangeability between manufacturers. Dimensional tolerances align with IEC 60269-2. For example, the typical blade width for a 200 A fuse-link is 25 mm ±0.5 mm.
Implementation Highlights
Adopting CAN CSA C50052-99 (2016) requires careful selection of fuse-links based on system voltage, available fault current, and coordination with upstream and downstream devices. Key implementation steps include:
- Determining maximum prospective short-circuit current at the installation point
- Selecting fuse-link rated current not less than 125% of continuous load current
- Verifying that the fuse-link’s I²t characteristic is compatible with the withstand of connected equipment
- Ensuring holders and bases comply with CSA C50052-99 for mechanical stability
Warning: Use of fuse-links not marked with the CSA C50052-99 designation may void equipment listing and cause non-compliance with Canadian Electrical Code requirements.
Compliance Notes
Manufacturers seeking certification must submit fuse-link samples to an accredited testing laboratory (e.g., CSA Group). The tests cover:
- Verification of rated breaking capacity under short-circuit conditions (Type 1 and Type 2 coordination tests)
- Overload performance at 150% of rated current for 30 minutes
- Dielectric voltage withstand at 2 × rated voltage + 1000 V (minimum 2500 V)
- Environmental conditioning: damp heat cyclic (42 days) and dry heat (48 hours)
Renewal of certification is required every five years unless the standard is reaffirmed. The 2016 reaffirmation did not introduce technical changes but confirmed existing requirements.
Compliance Benefit: Meeting CAN CSA C50052-99 (2016) simplifies equipment acceptance across Canadian provinces and aligns with international standards, facilitating export to markets adopting IEC 60269-2.
Q: Is CAN CSA C50052-99 (2016) identical to IEC 60269-2?
A: Yes, it is an identical adoption (IDT) except for Canadian deviations noted in an annex covering national wiring rules and ambient temperature adjustments for Canadian climatic conditions.
A: Yes, it is an identical adoption (IDT) except for Canadian deviations noted in an annex covering national wiring rules and ambient temperature adjustments for Canadian climatic conditions.
Q: What is the significance of the “-99” in the standard number?
A: It indicates the original year of adoption (1999). The (2016) signifies the reaffirmation confirming that the standard remains current without technical revision.
A: It indicates the original year of adoption (1999). The (2016) signifies the reaffirmation confirming that the standard remains current without technical revision.
Q: Do all industrial installations require CAN CSA C50052-99 fuse-links?
A: The Canadian Electrical Code mandates compliance for fuse-links used in circuits exceeding 125 A or where fault current exceeds 10 kA. Always consult local regulations for specific applications.
A: The Canadian Electrical Code mandates compliance for fuse-links used in circuits exceeding 125 A or where fault current exceeds 10 kA. Always consult local regulations for specific applications.
Q: Can I use gG or gM fuse-links interchangeably under this standard?
A: Both categories are covered. gG (general purpose) protects cables against overload and short-circuit, while gM (motor protection) allows higher inrush. The standard defines distinct testing criteria for each type: gM fuse-links undergo additional overload cycling tests per Clause 8.4.
A: Both categories are covered. gG (general purpose) protects cables against overload and short-circuit, while gM (motor protection) allows higher inrush. The standard defines distinct testing criteria for each type: gM fuse-links undergo additional overload cycling tests per Clause 8.4.
This article is for informational purposes only and does not replace the official standard document. Always refer to the latest published version of CAN CSA C50052-99 (2016) for full requirements. © 2026