Setting up relays to turn mains power on & off

I am after some information to pass over to my electrician on wiring up my 15amp mains power points that run all my power supplies. I have seen in chat over the last couple of years people talking about using the PI player to turn a relay on 10 minutes prior to the show starting & off at the end.

Any information, diagrams or specific relays that may be needed would be greatly appreciated.

Thanks
AussieDoug

 

Darylc is using one of the APC AP7100's i think. Others are using the Belkin wifi ones.


I mostly use computer power supplies that I currently manually turn on and off but next year I will be automating it with some basic relay modules.


You could possibly get away with the Kambrook wireless ones but depending on how much current each of your power supplies will be pulling, they might not last (i'm told the relays are not of that good a quality)

 

Hi Doug,


if this one cct is powering all your Power supplies you might investigate the option of installing a "d" curve MCB instead of the common "c" curve. This would reduce the possibility of tripping on inrush current on turn on. ( perhaps...insert disclaimer here..)


Cheers
Fing

 

I have 2 dedicated 15amp circuits for my display. If they were only 10amps I would buy a good old electric timer, hence the need for another solution.

 

SSR?

 

Solid state relay?

Trying to find something along those lines using a Ray Wu DMX as a switch.

 

I use David's Relay boards discussed here and available from his shop here

These work really well - I have two of them, with my power supplies spread across the eight relays.. I stagger them when turning them on to avoid inrush issues.

The relays that it uses are rated to 30A, so perhaps they'd suit 15A, although on the product page he mentions 10A, so may need to check with David..

Cheers

 

As discussed with Doug earlier on the phone, I'll be updating the 4 way relay board to have heaver tracks.

This will increase the current rating to 15 Amps (probably more).

 

David,

When you refresh the 4 way board is there any chance of a E1.31 interface instead of DMX.

DMX means I still have to keep a controller on as well as the PS to power it. This is on top of the Pi, it's power supply, and the network switch.

Just thinking of reducing devices that need to stay on.

Hopefully work will have a spare APC switched rail that I can permanently borrow in the near future ,making above null and void.

Regards,
Rowan

 

DMX / E1.31 is'nt really a good control protocol for using on safety critical thing and this is probally something you need to consider for this kind of app.


(a) what happens if the control signal to the "switch" doe'snt make it?
(b) what happens if you get something go wrong. Turning it on and off at 40frames/second may not be a good thign!
(c) how do you know if its on or off?

 

Sorry, I have no plans for any E1.31 devices.

The relay board has a 5V output that drives a DR4, etc do that DMX is always available. That's how I do it in my display.

My board also has enough smarts to prevent rapid cycling of the relays.

 

A suggestion and only a suggestion.. Practicality may not suit however in my mind it works well..


Have your electrician wire up a contactor to control the power circuit, which is wired to a PE cell (light level sensor) and set to dusk to x time mode.. Show powers up at dusk, and runs for 4 hours or what ever time period youset it too.. Could also have a auto/ofd/manual switched wired up for daytime use..


Cheers..

 

Some of you might be lucky to have previously had your electric oven removed and a gas oven put in it's place.

This means you now have a 32Amp power feed leftover in your switchbox.

A sparky can re-route this to wherever you need (front porch?) via a decent 40-45amp outlet.

I feed my 32Amp into a box with 3x 10Amp breakers in it, which allows me to now have 3x 10 amp outlets (regular 240v outlet sockets)
Each of my 10 amp circuits also has a power monitor plugged into it, they're inside a large plastic insulated box with a clear lid. This allows me to view the current draw on each circuit, so i can see if i'm loading 1 circuit more than the others.

The other bonus is that this 32Amp feed, won't have any effect on the 2x 10-15 amp feeds within your house, so no more flickering lights ;-)

Enjoy!

 

that a old one

 

You'd want to make those breakers RCD/MCBO combinations units as the 32A supply would not have been RCD protected.