Meaning old equipment that is no longer in common use but still in working order. Here is an example of usage:

"At the end of the life cycle of an item of technology, the issue arises as to whether it is more economical to use or dispose of obsolete equipment. As improvement in computer technology accelerates, this issue can arise within a year or two of purchase. In some cases, particularly where the technology will continue to perform satisfactorily notwithstanding that it is obsolete, it may be worth retaining. In other cases, it may be desirable to upgrade technology quickly in order to gain some benefit from reselling the old equipment while it retains some value. "

"Farmers hanging onto worn-out equipment because of the tax code's outdated
depreciation system soon could have a new incentive to purchase..."