The machine consists of a rotating table driven by a gear motor. There is a loading/unloading station in which the following series of operations occur:

1. The machine operator, protected by a security gate and a safety curtain to avoid injury, unloads the tested valves from the set of gauges and loads the valves to be tested.
2. The start cycle button is pressed, causing the rotating table to re-position the valves to a 2^nd position. The operator repeats the operation detailed in Step 1 in this new position and the valves are filled with pressurized air at a preset pressure.
3. Following this, the valves are brought to a 3^rd position in which no operation is performed, followed by another position and so forth until the valves get to the final station, in which the air pressure is measured again with pressure gauges. If the initial pressure value read in Step 2 minus the new read value is within the acceptable range, then the valve passes the testing and can be moved on. If not, the valve goes into a check area where another operator determines if it has been assembled properly and fixes the problem.

There are many advantages to using Horner controllers to perform quality control for automated systems. All defects in products are detected, due to the ability to test every product if needed (rather than a sample from a batch). Horner controllers also allow data to be collected about all defects and errors, which can be analyzed to minimise errors and save both time and money in the future.