Supporting All Your Safety Capacitor Needs

By Peter Matthews

In high-voltage and high-reliability applications, safety capacitors are essential for mitigating risks from transient voltages and electrical interference. They protect both users and equipment, even in the event of failure, by preventing hazardous conditions. Class X capacitors (across-the-line) are designed to fail short without creating shock risks, while Class Y capacitors (line-to-ground) are engineered to fail open, minimizing electric shock hazards. Both are further divided into subclasses based on voltage and impulse withstand ratings.

Knowles provides an extensive portfolio of safety-certified multilayer ceramic (MLC) and film capacitors tailored to demanding applications such as electric vehicle (EV) battery systems, industrial power supplies, motors, charging systems, and appliances.

For Class X capacitors, offerings range from 5.6 pF to 40 μF. Notable families include the SYX/UYX series (X1/Y2 rated, ideal for EV systems) and MXT Class X2 film capacitors, which pass stringent 85/85 temperature-humidity-bias testing for reliability in harsh conditions.

For Class Y capacitors, options span from 5 pF to 1 μF. These include the SYS series (Class X1/Y2 MLCCs with TÜV and UL approvals), the MYH film series (AEC-Q200 qualified, 2,000-hour THB tested), and other robust MLCC options.

Often, Class X and Class Y capacitors work together in circuits, such as EMI filters in AC/DC converters, combining MXT X capacitors with SYS Y capacitors for comprehensive safety.

With decades of expertise and a newly expanded range, Knowles ensures designers can meet safety, performance, and reliability requirements across diverse industries.