mixing voltages on relay

Discussion in 'General Discussion' started by markdem, Nov 24, 2013.

  1. markdem

    markdem

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    I am having a argument with myself trying to figure out if I can put 240 and 12VAC on one relay.

    Customer here wants to control outdoor lighting with a common tranny. OK, far request but they want the tranny to only power on only when they use the lights.

    So, I was thinking of putting a 8ch relay unit into a separate enclose and using CH 1-6 for the lights. CH7 would then be empty and CH8 would be to control the 240 feeding the tranny.

    Looking at AS3000, I can't see anything that really says "NO". If I leave ch7 empty I would comply with isolation requirements, and all cabling would be cable tied to prevent anything moving.

    Is there any resign I would not be able to do this?
     
    markdem, Nov 24, 2013
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  2. markdem

    DarylMc

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    There is a bus powered 8 channel low voltage relay L5108RELVP but is not on the CIS web site.
    Have a look and see if that is any use.

    http://updates.clipsal.com/ClipsalOnline/Files/Brochures/W0000938.pdf

    I imagine for your requirements that the low voltage lights being switched would not be close to the CBus relays anyway.
    Find a suitable location and enclosure, then mount a CBus controlled outlet there for the transformer.

    Trade price from Clipsal iCat is $750 for a non power supply 8 ch relay and $320 for the 8 ch L5108RELVP
     
    DarylMc, Nov 24, 2013
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  3. markdem

    markdem

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    I had a look at the LV relay, but 2A will not cut it here.

    Point is I wanted to have the transformer and relay in one enclose and did not want to use a CBus outlet to control the transformer. For lighting I guess I could get away with it, but I also need to do irrigation and would like to keep all the outputs in the irrigation app group. I guess I could use a single output relay for the transformer, but I would be nice if I could just fo it all with one relay..

    How does everyone else do it here?
     
    markdem, Nov 24, 2013
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  4. markdem

    ashleigh Moderator

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    Electrical safety advice applies here. Tread with extreme care.

    In principle separation by a spare channel (which should be taped or marked as NEVER TO BE USED) and segragation would probably be OK. But I'd be very wary.

    Suggest those who post answers consider very carefully before doing so as bad advice leading to electrocutions may lead to liability and embarrassment.
     
    ashleigh, Nov 25, 2013
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  5. markdem

    DarylMc

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    Hello Ashleigh
    Did it not come across clearly that I was suggesting he use the L5108RELVP low voltage relay in a separate enclosure to keep the low voltage wiring away from 240V terminals.
     
    Last edited by a moderator: Nov 25, 2013
    DarylMc, Nov 25, 2013
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  6. markdem

    ashleigh Moderator

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    Daryl: I did understand that. My point is that not going that way is something to be considered very carefully indeed.
     
    ashleigh, Nov 25, 2013
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  7. markdem

    DarylMc

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    Hi Ashleigh
    Sorry, I was just being paranoid since you didn't acknowledge anything I said.
    The reason I posted was to show a safer alternative to what he was planning to do.

    To be fair to the electrician who was wondering how to implement the low voltage components.
    The L5108RELVP is not even on the CIS website product list and is certainly the product he should be looking at for irrigation as well.
    Integrator websites are a much better source of information than CIS own.
    That's a credit to them but it shouldn't be the case.

    It is a reasonable option for markdem to use 3rd party low voltage relays controlled by the L5108RELVP if the contacts aren't suitable for the loads.
    This and a 5101RC to switch the transformer (if required) will meet his requirements as far as I can tell and get the low voltage wiring out of the electrical switchboard.

    I think that's the sort of information that should be available to markdem on this forum and CIS website.
    To the detriment of everyone who has a stake in CBus products it is not being well provided by CIS.
     
    DarylMc, Nov 25, 2013
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  8. markdem

    ashleigh Moderator

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    Yes, yes, yes and yes.:D
     
    ashleigh, Nov 26, 2013
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  9. markdem

    markdem

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    Hmm, from the above I think I will just go with the single relay to control the high side and leave the 8ch relays to LV only.

    Thanks guys.
     
    markdem, Nov 26, 2013
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  10. markdem

    Matthew

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    I use the L5108RELVP to control the 12V DC irrigation soleniods.
    Use a std L55xxRVF (at the switchboard) to control the mains into the outdoor lighting transformers (mounted on external wall). That way keep the LV cabling in the garden and as short as possible.
     
    Matthew, Dec 10, 2013
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