I'm writing a book and one the characters is in a psych ward. I've been researching but I'd like opinions from real people. Anything you can tell me about this place would help so much. Experience etc?

I am willing to help you. I have been in both public/private psych hospitals.
To answer your above questions-
Attempted suicide can lead to being scheduled ( sectioned, whatever you call it where you are) for 72 hours (I think). This is where you are forced to stay in hospital by either police or by a doctor. Public hospitals don't have radios or any electronics in the room because these can be used as weapons or smashed and used in self harm. Visitors are allowed but can be refused by patients or sometimes doctors might say it's best not to have visitors.
Any more questions- let me know :)

Psych wards are horrible places, you confined to a tiny space, depending on whats wrong with you you can have 24 hour survailance, there is nothing to do except read a book or watch one of the very few movies provided. The food is disgusting and sometimes you hear people yelling and screaming completely random things.

Anything in particular you'd like to know?

P.s not from personal experience, but I work in mental health :P