A test rig that made divert switches worth repairing

Expensive, complex, and untestable

Divert switches steer packages through a high-speed sorting system. They are expensive, mechanically complex, and contain up to four small stepper motors each, any one of which can be the fault.

With no way to test a switch before it failed, maintenance teams had no basis for a repair decision — so they replaced complete units. That was costly, wasteful, and still left them exposed to unplanned breakdowns during peak throughput, which is precisely when a sorter cannot afford to lose a divert.

Build the missing test method

The blocker was not repair capability; it was the absence of a way to assess a unit. A bespoke test rig was designed and built to evaluate each divert switch properly, testing every stepper motor individually to confirm it was operating within parameters.

That single change reframed the whole maintenance approach. Once a switch can be measured, a marginal motor becomes a scheduled repair instead of an unplanned failure.

• Each of the one to four stepper motors per switch tested individually
• Live motor performance monitoring to catch excessive current draw or erratic motion early
• Coil resistance checks and winding health analysis against performance standards
• Early fault detection, allowing intervention before a switch strands a sorter

Targeted repairs instead of wholesale replacement

Maintenance teams gained a way to monitor divert switch health and act on it. Premature replacement of serviceable units stopped, maintenance costs fell, and unexpected breakdowns became less frequent — including through peak demand.

The rig has since become a standing part of the operator's preventative maintenance programme rather than a one-off diagnostic exercise.