This topic contains 3 replies, has 2 voices, and was last updated by  Ray 1 year, 2 months ago.

Viewing 4 posts - 1 through 4 (of 4 total)
  • Author
    Posts
  • #50722

    trevor.shirran
    Participant

    Hi,
    Is there a way of driving relays rather then valves?
    I would like to use the output to operate other devices before the valve.
    I understand my DC version will power DC 12 v valves or 24v ac so reluctant to put a relay on the output before asking as it will obviously do some sort of checking first. I read there will be a high pulse then holding current.
    Trev

    #50958

    Ray
    Keymaster

    If you have a DC-powered OpenSprinkler, it can drive 5VDC relays or 12VDC relays — for 5VDC relays the default power adapter should work fine, for 12VDC relays, you should change to a 12VDC power adapter (the controller itself can accept any input voltage from 5VDC to 12VDC). The impulse high voltage is generally fine for relays because it only lasts for a couple hundred milliseconds and won’t damage the relays. Also, you can turn off the boosting time (in Edit Options -> Advanced, change Boosting time to 0) to avoid the impulse voltage.

    If you have an AC-powered OpenSprinkler, it can drive 24VAC relays.

    #50971

    trevor.shirran
    Participant

    Thanks for the reply Ray, I must admit I missed the boost option.
    I assume if I go down the 5/12 v DC relay option I will not need to use a back emf diode as the triac is the initial switch.
    Trev

    #51120

    Ray
    Keymaster

    There is already a TVS diode on each zone for transient voltage protection. Also, if you use a relay module (instead of an individual relay directly) — the relay module’s control pin is generally connected to a opto-isolator, which turns on relay and has built-in flyback diode on the relay side. So if you use a relay module, the flyback diode is already included. In sum, you don’t need flyback diode either way.

Viewing 4 posts - 1 through 4 (of 4 total)

You must be logged in to reply to this topic.