HZ40A6A242 by Danaher

The HZ40A6A242 is a preset counter produced by Danaher within the Timers and Controllers series. Designed for panel-mounted automation assemblies, this unit registers pulses coming from proximity switches or limit contacts and energizes its relay output after the programmed quantity is reached. In material-handling lines or batch-production stations, it offers simple sequencing without the need for a PLC, ensuring that conveyors, feeders, or clutches change state only after the required number of parts passes its sensor.

The relay output is rated for 15 A, allowing the counter to switch moderate-power solenoids, heater contactors, or small motors directly. Its movable and stationary contacts are plated with silver, a material chosen for low resistance and high endurance against arc erosion. The device provides 3 independent contact sets that transfer simultaneously at the preset threshold, permitting simultaneous control of multiple circuits. Counting is referenced to the trailing edge of each input pulse, eliminating false increments that can occur from contact bounce on the leading edge. The register can advance up to 400 counts, so users may assign any preset from 1 to 400 before the relay toggles.

Resetting the counter after a cycle is performed by an electric reset coil that clears the internal decade wheels without operator intervention. The front panel includes a lockable setpoint knob so the chosen preset can be secured against unauthorized changes during shift operation. Internal timing circuits synchronize to a 60 Hz line frequency, maintaining consistent count discrimination in facilities using the North American mains standard. All logic and coil functions draw power from a single 120 VAC source, simplifying wiring within control cabinets and removing the need for auxiliary low-voltage supplies.