What are the differences between safety gauge capacitors and regular capacitors?

1. The discharge of safety-gauge capacitors is not the same as ordinary capacitors

Ordinary capacitors will retain their charge for a long time after the external power supply is disconnected, and if you touch them with your hands, you will be electrocuted. While the safety gauge capacitors do not have this problem, safety gauge capacitors fail, will not lead to electric shock, does not jeopardize personal safety.
Safety capacitors include X and Y capacitors.
At the AC power input, three additional safety capacitors are generally required to suppress EMI conducted interference.
The x-capacitor is the capacitor connected across the power line between the two lines (L-N), generally choose metal film capacitors; Y-capacitor is the capacitor connected across the power line between the two lines and the ground (L-E, N-E) respectively, generally appear in pairs. Based on the leakage current limit, Y capacitance value can not be too large, generally X capacitance is uF level, Y capacitance is nF level. X capacitance suppresses differential mode interference, Y capacitance suppresses common mode interference.

The Y capacitor is connected to the capacitor between the fire wire (L) and ground wire (E) and between the zero wire (N) and ground wire (E).The Y capacitor connection position is relatively critical, and must comply with the relevant safety standards in order to prevent the equipment leakage caused by equipment or casing charged to endanger personal safety. Generally in the subtropical machine requirements to the ground leakage current can not exceed 0.7mA, in the temperate zone of the machine requirements to the ground leakage current can not exceed 0.35mA. Therefore, the total capacity of the Y capacitor can not exceed 4700pF (472).

2.Difference between safety-gauge capacitors and ordinary capacitors
1.Certification is different.
Ordinary CBB capacitors, it does not need any certification, but safety capacitors generally have to go through a lot of certificates, such as CQC, VDE, UL, CUL, etc., and the more certificates the better.
2, safety capacitors are mainly for X capacitors and Y capacitors

X capacitors for the suppression of differential mode interference, generally across the connection between L and N (N on behalf of the zero line, L on behalf of the firewire), the common is X1 capacitors and X2 capacitors. Each grade has a different withstand voltage. Failure will not be harmful.
Safety Y capacitors are subdivided into Y1 capacitors and Y2 capacitors, in order to inhibit common mode interference, Y capacitors are safety series capacitors, capacitors connected in parallel between the fire wire and the ground wire as well as between the zero wire and the ground wire are collectively referred to as Y capacitors. Generally there will be leakage current.
Safety capacitors are mainly used in power supply electronic instruments and electronic equipment, applied to switches, contacts and other parts of the spark discharge, can play a role in absorbing pulse interference and reduce electromagnetic nuisance.
CBB capacitors are widely used in all kinds of electronic equipment, differential motors, power tools, lighting fixtures, air conditioners, refrigerators, washing machines and other household appliances, as well as power systems.

3, different appearance.

Like X class safety capacitors, generally installed in the plastic shell, ordinary CBB capacitors, most of them are epoxy resin encapsulated.

4, the price is different.

The same capacity, the same voltage, safety capacitors are relatively more expensive, because these capacitors have to spend a lot of certification costs each year, and the production process is also different.