IEC 62368-1 is a hazard-based standard for Information Technology Equipment (ITE) and Audio/Visual (A/V) products. This standard approaches overvoltage protection in a different way than the more prescriptive, incident-based standards of the past, namely IEC/EN/UL/CSA 60065 and IEC/EN/UL/CSA 60950-1.
What is Overvoltage?
Voltage, defined as the amount of potential energy between two points, applies to everything from AAA batteries to a commercial dryer. Overvoltage refers to a voltage that exceeds the maximum voltage that the system or product is designed to handle.
Overvoltage can occur in both low-voltage and high-voltage networks, depending on the conditions and the systems in play. Some common types of overvoltage include
- Surges
and switching overvoltage - This can
occur when large charges (such as a transformer, motor, or even a
refrigerator or dryer) are switched on or off. A surge can also occur due
to voltage fluctuations on the part of the power utility provider or the
power source. This kind of overvoltage may only last a fraction of a
second, but it can still damage some electronic devices.
- Insulation
failure - Putting insulation between the
power line and the earth encourages the current to flow downward; if the
conductor is not properly grounded, it can result in dangerous
overvoltage.
- Atmospheric
overvoltage - This is typically the result of
a lightning strike, and it often occurs on overhead lines or unshielded
cables. Atmospheric overvoltage is particularly dangerous because
lightning can increase the voltage by many times its normal levels,
leading to very hazardous levels of electricity.
Overvoltage and 62368-1
The IEC 62368-1 standard defines categories of overvoltage for ITE and A/V products. Each overvoltage category has a corresponding peak voltage level that product designers and manufacturers need to pay attention to.
For example, ITE products that connect to the wiring of a building are classified as overvoltage category II. This category has a transient peak voltage level 1.5 kV for 120 V ac, and 2.5 kV for 230 V ac.
Other components of the electrical system have their own overvoltage protection requirements. Gas Discharge Tubes (GDT), for example, has to provide sufficient insulation, external clearance, and creepage distance to prevent sparkover during testing. The requirements for a given product are based on transient voltage, working voltages, recurring voltages, and temporary overvoltages. These values, contained in several different tables in the 62368-1 standard, determine what specific criteria the product must meet during testing.
G&M Compliance Can Help With Overvoltage Requirements
There are multiple ways to transition to 62368-1 successfully, depending on your product and your target markets. Similarly, there are multiple ways to approach overvoltage safety and compliance. This may involve the GDT or metal oxide varistors (MOV), or improving the insulation withstand voltage of the equipment itself.
G&M Compliance can help you determine the best path for your situation. Whether it’s a new Low Voltage Directive (LVD) report, vetting the compliance of component parts, or refreshing the global certification scheme, G&M Compliance can help.
Contact
G&M Compliance for more information
about preventing overvoltage or demonstrating compliance with IEC 62368-1.