cgsecurity.org

Recovery time of files from the HDD with unreadable sectors can be a few days.
Does PhotoRec is a parameter that specifies the maximum time to read of one sector?

The timeout is at the OS level, PhotoRec have to wait for the OS to ask for the next sector.
If there are a lot of bad sectors, it's better to create an image of the damaged media and use PhotoRec on it.
http://www.cgsecurity.org/wiki/Damaged_Hard_Disk