It is always the job of preset counters to trigger a signal at a particular count value. In the simplest instance this can mean just shutting down a machine, however it could also be the initialisation of control functions (e.g. cutting material to length, transporting parts etc.). Relays, transistors or optocouplers are used as outputs.
Relays are suitable for switching heavy loads (up to 2000 VA). The actual switching capacity depends on the model (counter) and can be seen in the data sheet. Most relays are available with a changeover function.
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