Class 2 Standard in Electricity: Safety and Performance in Lighting

Class 2 Standard in Electricity: Safety and Performance in Lighting

The Class 2 standard is an electrical safety regulation that governs the limits of current, voltage, and power (amperage) in circuits to ensure a high level of safety, especially for low-voltage applications like LED lighting. For lighting purposes, this standard enforces strict limits on the maximum allowable power to prevent overheating or electrical accidents. For example, our LED strips, which are CUL certified, must be connected to a Class 2 transformer to maintain this certification.
Understanding Class 2 Limits

The Class 2 standard sets a safety ceiling for low-voltage circuits, typically:

30 volts maximum voltage,
5 amperes maximum current,
100 watts maximum power.

The maximum power (or wattage) is calculated by multiplying voltage by amperage:

Wattage = Voltage x Amperage

These values are established by regulatory bodies like Quebec’s Régie du Bâtiment, the ESC in Canada, and safety standards in the United States.

Applying Limits in 12-Volt and 24-Volt Circuits

In lighting, these limits translate to different maximum power allowances depending on the type of circuit:

12-Volt Circuit
With a 5-amp limit, a 12-volt circuit is limited to 60 watts:
12 volts x 5 amps = 60 watts.

This power limit ensures compliance with the Class 2 standard for 12-volt circuits, where the allowable maximum power is more restricted. LED strips connected to 12-volt circuits are thus capped at 60 watts to prevent overheating and overcurrent.

24-Volt Circuit
In 24-volt circuits, the maximum allowable power is close to the 100-watt limit:
24 volts x 4 amps = 96 watts.

This makes a 24-volt circuit suitable for higher power levels while staying within Class 2 limits. This higher capacity makes it a popular choice in installations where longer or more powerful LED strips are needed. With a higher voltage, line losses are minimized, allowing for longer LED strip sections with optimal efficiency.

Why Are Class 2 Circuits Safer?

The Class 2 standard’s limits are primarily in place to ensure user and installation safety. With low voltage and limited power, these circuits are designed to minimize the risk of serious incidents if a fault occurs. If a problem arises (such as an overload or short circuit), circuit components generally overheat and melt, thereby cutting off the circuit instead of creating electrical arcs or discharges that could spark a fire.

In other words, Class 2 circuits are designed for intrinsic safety: they keep components below critical thresholds, reducing the risk of overcurrent. If a failure occurs, the circuit is designed to shut down gently, without posing a hazard to people or nearby equipment.
Summary: Power Limits by Voltage

12 volts: Maximum power of 60 watts per circuit.
24 volts: Maximum power of 96 watts (near the 100-watt allowance).

Benefits of 24-Volt Circuits

24-volt circuits are often preferred for large-scale lighting installations for several reasons:

Lower losses over longer distances, thanks to the higher voltage,
Ability to power longer LED strips and manage more powerful components,
Improved energy efficiency for projects requiring higher light intensity.

Conclusion

The Class 2 standard is essential in LED lighting to ensure safe use, especially in residential and commercial installations. By limiting power, current, and voltage, this standard creates low-voltage installations with minimal risks in case of a fault. With these restrictions, Class 2 circuits provide a safety barrier that prevents the dangers of fires and electric shocks while enabling efficient and durable lighting solutions.

For all these reasons, adhering to Class 2 specifications in the design and installation of LED lighting systems is crucial, whether for 12-volt or 24-volt circuits.