Control/Dimming Using relays with 'standard appliances'

techietim

Active Member
Joined
May 7, 2012
Location
England, UK
Hello!

Also, before I continue, I'm in the UK when I reference mains/connectors etc...

I recently purchased a 3 channel DMX controlled relay unit with 10A switching per channel. I was wondering if I could create some kind of cable that would enable something like a lamp or prac prop to be connected (i.e. something that draws less than 10A).

My thoughts so far are getting a really short mains extension cable (sticking a 10A fuse or less in too of course!) and then butt splicing or 'closed end terminal'ing the earth and neutral and connecting the live into the switch.
Is it best to switch the live rather than neutral? (Obviously not earth :p)

Maybe there is already a perfectly good solution or obvious one - I'd be keen to hear. Especially if I'm about to do something incredibly stupid or dangerous - that would be bad!

Thanks.
 

techietim

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Joined
May 7, 2012
Location
England, UK

DavidNorth

ETC Rigging General Manager
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This is true, however as I bought the relay to control a smoke machine and thought it would be good to have it multipurpose!
Hmmm, be careful. I looked up the relays and they are only rated at 3A [125V, no 250V number] for inductive loads. The 10A rating is for resistive loads and there is no listing for tungsten, so they probably never assessed that. Depending on how the smoke machine is built, it could be anywhere from mostly resistive to mostly inductive. This relay box might be ok, but don't be surprised if at some point it fails with relays stuck on, stuck off or pops the relay entirely.

What is the wattage rating of the smoke machine?

David
 

techietim

Active Member
Joined
May 7, 2012
Location
England, UK
Hi David,

Can you link us to the data sheet? That would be handy!

Thanks.
 

techietim

Active Member
Joined
May 7, 2012
Location
England, UK
Thanks David - will have a look soon. :)