It's not so much about the format, as it is about the continuity for the reader and making the reader care about the new POV.
If you're going to have a secondary character's POV, and you only use it once in an entire 400-page novel, it's going to feel weird to the reader. Foreign and incomplete. Then, if you do it again with another secondary character who has only one POV scene, it's going to get irritating. A single scene isn't long enough to really bond with a character after the reader has bonded with the protagonist, and the reader's going to be thinking, "All right, already, let's get on with the story. I don't know this person; I want to know what the protagonist is doing."
On the other hand, if you have just one secondary character's POV in, say, three different scenes (three is a comfortable number for many, many things), spread out over the course of the book, there will be some continuity and familiarity for the reader. It will feel like it's done on purpose, not just for the author's convenience.
So, make sure there's either a reason why the READER would enjoy being in that secondary character's head (and not just a reason why it's convenient for you, the author, to present the requisite information that way), or else stay out of it and find another way to present the information. There's always another way.
JD