Class-X and Class-Y capacitors are safety-certified and generally designed and used in AC line filtering in many electronic device applications. These safety capacitors are also known by other names, including EMI/RFI suppression capacitors and AC line filter safety capacitors. (EMI stands for electromagnetic interference. Class-X and Class-Y capacitors are classified according to: 1. their peak voltage/rated voltage and 2. the peak impulse voltage that they. Subclass X2 and Y2 are the most commonly used safety-certified capacitors. Depending upon your own application and requirements, they are. Because Class-X and Class-Y capacitors must be connected directly to AC lines (line-to-neutral or line-to-ground) in order for them to perform their EMI and RFI filtering functions, they. All safety-certified capacitors should have the proper logo markings/symbols on their casing. See Figure 4 below for an example and see Figure 5 for a definition/description of these logos:.
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What is a Certified Safety capacitor?
Certified Safety Capacitors are vital components for safety critical across-the-line and line-to-chassis applications. X-class capacitors are used across the line where failure would not lead to an electrical shock. X-class capacitors are divided into sub-classes by its rated and pulse voltage. See Table 1. Table 1.
What is a Class Y safety capacitor?
These safety capacitors are also known by other names, including EMI/RFI suppression capacitors and AC line filter safety capacitors. (EMI stands for electromagnetic interference and RFI stands for radio-frequency interference; RFI is simply higher-frequency EMI.) Figure 1. An example of a Class-Y capacitor. Image from this teardown.
What are x & y safety capacitors?
X and Y safety capacitors filter AC signals and reduce EMI, so they are directly connected to hazardous AC mains voltages and must be certified as "safety capacitors" to ensure safe operation under these conditions. There are various types of safety capacitors used in safety filter circuits.
Are class X and Class Y capacitors safe?
Because Class-X and Class-Y capacitors must be connected directly to AC lines (line-to-neutral or line-to-ground) in order for them to perform their EMI and RFI filtering functions, they must be rated and certified as "safety capacitors." Both Class-X and Class-Y capacitors have subclasses: subclass X1, X2, and X3, and subclass Y1, Y2, Y3, and Y4.
What are X-class safety capacitors?
X-class safety capacitors classification Y-class capacitors are used in “line-to-ground” applications where failure could lead to an electrical shock. It is also divided into sub-classes by their AC voltage and peak surge voltage ratings. See Table 2.
Normally a Class Y safety capacitor is recommended for this, but a Class X safety capacitor could also be used. The idea here is that the connection allows high-frequency noise currents to pass between the grounds as needed rather than allowing them to radiate their energy away from the PCB. The world's most trusted PCB design system.