Product Description:

Danaher manufactures the HZ170A601 mechanical preset counter within its Timers and Controllers series. The unit combines an electromechanical clutch with multipole relay contacts so a machine builder can add count-based shutdown, indexing, or dwell control to a conveyor, press, or packaging station. It advances one count per pulse, then drives two instantaneous SPDT relays and two delayed SPDT relays to transfer signals to downstream logic.

The counter is powered by a 120 VAC supply, which aligns with common control transformers. At that voltage, the relay contacts can switch loads up to 10 A at 120 VAC, allowing direct control of heaters, pilot valves, or small motors. Counting performance reaches 500 counts/min, so sensors must provide clean signals that meet the required 40 ms pulse-on and 80 ms pulse-off times. A front dial lets the operator choose any value up to 100 counts. When the counter reaches that preset, the clutch disengages after a 50 ms pull-in period and shifts the delayed contacts. Counting accuracy is 100 percent under the rated operating conditions. The mechanism draws 10.5 VA while holding, 16 VA during inrush, and 26 VA when the stepping solenoid first engages.

The dial can be set to a minimum of 2 counts for short indexing moves, providing flexibility at the lower end of the counter’s range. The coil operates on a 50/60 Hz line without requiring jumper changes. A spring-return reset clears the register in 500 ms, permitting rapid cycling between batches. The mechanism uses a reverse clutch, so the gear train backs away from the ratchet after reaching the preset instead of overrunning it. This action minimizes wear during continuous operation while preparing the mechanism for its next counting cycle.