Difference between Y1 and Y2 capacitors

There are many types of Y capacitors, including Y1, Y2, Y3, and Y4, among which Y1 and Y2 capacitors are used most frequently.
Y1 and Y2 capacitors are not exactly the same, what is the difference between them?

Y2 Capacitor

1), the withstand voltage is different.

The rated voltage of Y1 is ≤500VAC, the peak voltage is equal to 8 kV, and the experimental voltage is 4000VAC.

Y2 rated voltage ≥ 150VAC ≤ 500VAC, peak voltage equal to 5 kV, test voltage 1500VAC,

2), the foot distance is not the same.

The conventional pitch of the Y1 capacitor is 10mm.

The conventional pitch of the Y2 capacitor is 7.5mm.

3), the insulation type is not the same.

Y1 belongs to double insulation or reinforced insulation.

Y2 belongs to basic insulation or supplementary insulation.

4), the size is not the same.

In the case of the same volume, the volume of the Y1 capacitor is appropriately larger than that of the Y2 capacitor.

5), the function of the product is not the same.

The Y1 capacitor is used to bridge the primary and secondary sides.

The Y2 capacitor is used to connect the primary side to protect the ground, which is the FG line; FG is the ground.