Re: Geovision Automation

[Kevin Hawkins <yahoogroupskh@xxxxxxxxxxxxxx>]

Hi Marc,

You're along the right lines... :-)

Bascially the rating on the Net I/O card indicates what sort of
current it could switch if it was run at that voltage - the 125V
probably being the highest voltage it can be used at and probably an AC
(rather than DC rating).  You could actually use it any any voltage upto
the 125V.   Since you need to switch 230V mains this is somewhat
acedemic and so you should correctly go for a 12V relay with 240V rated
contacts rated at a bit above whatever you wanted to switch current
wise. You mention 16A - that's a lot of current and running costs ,
just under 4KW of lighting !  Anyway being over on the current rating on
the relay is a good thing although it will make the relay  clunkier and
costlier.

Yes - you only need SPST if you want the lights to be ON when
energised,  if you need anything else to be on when NOT energised then
get a SPCO (changeover) instead.   Only if you had two separate fused
feeds for segments of this lighting then you might want DPST (dual pole)
or two relays  Consider the mounting of the relay and how it will be
wired - so that your sparky can do a neat and safe job. Maybe it can
mount in your consumer unit on the DIN rail for example if you have
one.  You can buy small plastic boxes that hold a few inches of DIN rail
as well . Some relays plug into a base that mounts on the DIN rail. As
this is external lighting you will need appropriate cabling outside and
you will also need current leakage breakers (MCB's) on the circuit
installed inside. The sparky will sort this.

I dont know anything about the Net I/O card but from what you say it
seems to have a small internal relay. If so then, just as you say, this
is wired in series  with a 12V supply (that you have to provide) to your
relay -  although conventionally most people switch the + rather than
the - side...If you can send me the manual by email I'll take a read
over it for you...

cheers Kevin


You need Marc Fuller wrote:
>
> Hey guys,
>
> I'm after some help with wiring up the NET I/O card with some
lighting.
>
> Specifically I am having problems locating a suitable relay. I am
trying
> to control some perimeter lighting. I'm not totally sure of the
> voltage/amps yet but let's assume the lights are running at 240v and
> 16amps.
>
> So, I don't want to put that load through the NET I/O card so I will
> need a relay. From what I've read on the NET I/O card it can switch up
> to 12vdc up to 1amp or 125vac up to .3amp. Is that correct ? or does
is
> specifically need to be 12v 1am or 125v .3 amp ?
>
> So let's use 12vdc as an example. So I need a relay that when I supply
> 12vdc, it switches the 240v contacts. I think this also means I need a
> SPST relay. Correct ?
>
> So how do I wire that into the NET I/O card ? Do I need a 12vdc power
> supply that I then feed into the NET I/O card which will then pass
that
> voltage on ? e.g the 12vdc positive goes straight to the relay, then
the
> 12vdc negative goes to either the GROUND or OUTPUT PIN1 of the NET I/O
> card. If I put the 12vdc negative to GROUND, then OUTPUT PIN1 goes to
> the negative coil contact on the relay. Thus when the NET I/O card
> activates the output, the 12vdc negative goes from GROUND to PIN1 and
> thus activates the relay.
>
> Phew.. that's a lot to take in for a non-sparky like myself. Is this
all
> correct ? If it is, does anyone know of suitable relays ?
>
> I must admit I'm a bit lost on all this. I will point out though that
I
> won't be wiring the relay myself, a sparky will be doing it but he
> doesn't understand what I need from him, so I am trying to get it
> straight in my head before I pass it on to him.
>
> Any help much appreciated
>
> Marc
>
>


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