Are you asking if we turn it off while digging a target? No. I dont turn it off until I'm done hunting. A fully charged battery gives me a full days hunt and then some.
I suppose that if you were running out of battery and trying to hunt as long as possible, that could give you a wee bit more time.
I won't usually, unless I know that I'm digging a huge piece of deep iron that is going to take a while to get out, in which case I will turn off my detector to save the batteries.