Patent attributes
A pallet wrapping system with a pre-stretch carriage and at least two encoders. The pre-stretch carriage is configured to pre-stretch stretch film and has at least two stretch rollers and a hinged door. The at least two stretch rollers includes a first stretch roller with an outer surface that moves at a first speed and a second stretch roller with an outer surface that moves at a second speed higher than the first speed. The door provides access to the stretch rollers when in an open position and entraps the stretch film between the stretch rollers and the door when in a closed position. The encoders are mounted on the door. Each of the encoders is configured to contact the stretch film on the outer surface of one of the stretch rollers and measure a length of stretch film passing over that stretch roller.