viper:
The information that serviceman gave you is in the HAAS manual, and I believe the on-line manual covers this.
The output relays are small electromechanical. Meaning they have physical contacts.
Are you going to switch an AC or DC solenoid? If supplying AC to an AC solenoid, then you do not use a diode, and maybe use nothing. If it is a DC solenoid then you put a back biased diode across the solenoid coil at the coil. But I do not recommend switching a DC inductive load with mechanical contacts.
Actually I would recommend use of a solid-state switch for either an AC or DC load and pilot this from the HAAS relay contact. Usually you will require a different type of SSR (solid-state relay) for DC relative to AC.
In general AC solenoids have better pull-in characteristics, and less average power dissipation than DC solenoids for a comparable capability.
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