"Se" is a difficult particle. It always means a different thing.
I don't understand the grammar book on this, but I'll explain it as I understand:
For me, this construction makes an impersonal imperative, formed with the imperative for "usted" and "se":
- Acátese la orden. -> This order must be obeyed by the reader.
- Véase la página 30. -> Refer to page 3.
- Ábrase aquí. -> Some packages have this label where you're supposed to tear or cut open.
