zuloowell.blogg.se - Ev nova x2 mode

To be clear, you should select your Class-X and Class-Y capacitors according to your design's purpose and requirements. This is assumed because X2 and Y2 safety capacitors are used in common appliances that operate from ordinary household wall outlets. Depending upon your own application and requirements, they are probably the ones you'll want to use. Subclass X2 and Y2 are the most commonly used safety-certified capacitors.

CAN/CSA 384-14: across-the-line applicationsĪpplications for Class-X and Class-Y Capacitors.

CAN/CSA C22.2 No.1: across-the-line applications.

UL 1283: American standard for electromagnetic interference filters.

UL 1414: American standard for across-the-line applications.

* Per the following international standards, according to Kemet (PDF): Tables 1 and 2 below summarize the subclasses of Class-X and Class-Y capacitors.

the peak impulse voltage that they can safely withstand.

Rating of Class-X and Class-Y CapacitorsĬlass-X and Class-Y capacitors are classified according to: Placement of Class-X (C X) and Class-Y (C Y) safety capacitors. A failure will cause your electronic device to be subjected to the noise and interference that the capacitor would normally filter out, but at least there will be no fatal electric shock hazard.įigure 2. Class-Y safety capacitors are designed to fail open. If a Class-Y capacitor, also known as the "line to ground capacitor" or "the line bypass capacitor"-the capacitor placed between line and ground-fails short, this could lead to a fatal electric shock due to the loss of the ground connection. Therefore, a capacitor failing in this fashion would not cause any electrical shock hazards. This failure, in turn, would cause an overcurrent protective device, like a fuse or circuit breaker, to open.

When a Class-X capacitor, also referred to as an "across the line capacitor"-the capacitor placed between line and neutral-fails because of an overvoltage event, it is likely to fail short. Thus, capacitor failure is a very real possibility. And because of this direct connection to the AC voltage, the capacitors may be subjected to overvoltages and/or voltage transients-lightning strikes, power surges. In order for these capacitors to perform their EMI/RFI filtering tasks, they are directly connected to the AC power input, that is, the AC “line” and the AC “neutral” (see Figure 2 below). Image from this teardown.Ĭlass-X and Class-Y capacitors help to minimize the generation of EMI/RFI and the negative effects associated with received EMI/RFI. (EMI stands for electromagnetic interference and RFI stands for radio-frequency interference RFI is simply higher-frequency EMI.)įigure 1. These safety capacitors are also known by other names, including EMI/RFI suppression capacitors and AC line filter safety capacitors.

A Special Class of CapacitorsĬlass-X and Class-Y capacitors are safety-certified and generally designed and used in AC line filtering in many electronic device applications. Learn about Class-X and Class-Y capacitors, where they are used, and why they are referred to as "safety" capacitors.