A new, large machine will begin sorting parcels and bundles of mail Monday at the Salt Lake Main Post Office.

After five weeks of setup and testing, the "small parcel and bundle sorter," SPBS for short, will be officially accepted by the post office at 10 a.m. Monday. The machine, manufactured by Unisys, cost $519,221 and is the first SPBS in the state.The word "small" in the machine's name refers to the size of the packages it sorts. The machine is 160 feet long and ranges from 22 to 44 feet wide. It sorts bundles and parcels weighing up to 20 pounds and measuring up to 8 inches by 12 inches by 15 inches.

Six employees work at individual stations on the machine, where they punch in the parcel's ZIP Code on a 10-key pad. The machine then weighs the parcel and quickly moves it on a conveyor belt to the correct bin.

The SPBS minimizes rehandling of mail, sorts it with fewer errors and uses fewer people than manual operation, said Ralph Thornton, manager of the Main Post Office's general mail facility. He expects use of the machine to result in an annual cost savings of about $163,000.

"Right now it sorts bundles at about the same speed as our employees do manually, and it sorts parcels twice as fast," said Thornton. "Once we get all the bugs worked out, the speed will greatly increase."