HZ40A6 by Danaher

The HZ40A6 is a panel-mounted timer and counter manufactured by Danaher for its Timers and Controllers series. Housed in a compact enclosure suitable for control cabinets, the unit accepts machine or sensor pulses, tallies them internally, and activates relay outputs when the selected preset is reached. By combining timing and counting functions in one device, it automates routine indexing, material feed length monitoring, and short-run batching without the need for PLC programming. This functionality makes it a practical component for legacy or standalone industrial equipment.

Power for the module is supplied through a 120 VAC line, and its internal timing circuit is synchronized to the mains at 60 Hz, which maintains stable timing without an external clock. Each of the three output relays carries up to 15 A, so the counter can switch solenoids, motor starters, or pilot loads directly without interposing devices. The switching elements use silver contacts to minimize resistive losses and contact erosion during repetitive cycling in high-duty machinery. The unit provides three independent contact sets for routing separate control, indication, and interlock circuits from the same preset event. This arrangement reduces field wiring while maintaining separation between the connected circuits.

Counting logic inside the HZ40A6 registers each transaction on the trailing edge of the input pulse, helping prevent double counting caused by contact bounce or electrical noise. The maximum factory preset is 400, providing sufficient range for batch counting or sequential process steps. An electrical reset allows the register to return to zero through a momentary push button or remote contact, eliminating the need for a mechanical lever. Desired totals are entered with a finely graduated micrometer dial, which supports precise adjustment from the front panel. The setting can be secured with a lockable pointer knob to prevent inadvertent changes during operation or shift changes. These controls allow the count target to be entered, protected, and reset without opening the control cabinet.