Offline SMPS: Primary to secondary Hi-Pot test?

[cupoftea]

Hi,
When doing a Hi-Pot test on an offline SMPS…when you are doing the primary to secondary….should you always earth the secondary?
This is because doing so means less voltage stress to the secondary to earth. Also, it also means you do the primary to earth hi-pot test aswell.

 

[FvM]

Depends on the specified test voltages. A typical power supply specifies e.g.
I/P-O/P:3KVAC I/P-FG:2KVAC O/P-FG:0.5KVAC (Meanwell RSP2400)
You can connect O/P to FG for the I/P-O/P test but need to apply 3 KV though.

 

[cupoftea]

You can connect O/P to FG for the I/P-O/P test but need to apply 3 KV though.

Thanks, thats a good point....i was told that connecting output to earth for the I/P to O/P hipot test actually reduces the voltage stress from output to ground, which occurs during the I/P to O/P hipot test , if that makes sense?

(despte the fact that its 3kv you're applying)