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Gizmo

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Joined: 05/06/2004
Location: Australia
Posts: 5116

Posted: 06:15pm 27 Oct 2015

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Hiya

Working on a project for a customer, a workshop siren. Based on a colour maximite from CircuitGizmos, it displays the time, and sounds a workshop siren for lunch breaks, end of shift, etc. You can set up different siren times for different weekdays, and even add public holiday dates, to silent the alarm. Once I've finished it I'll share it here.

To drive the siren, I was going to include a mains rated relay and get the customer to use an electrician to wire up a siren via the relay contacts. But this can be a problem. I no longer have an electrical ticket, therefore I need to build the device using a plug pack supply and no 240 wiring of my own. Plus I wont be there to install the thing anyway, the workshop is 1000km away. So I went looking for a simpler option.

Bunnings ( also seen similar at Jaycar ) have a Arlec remote operated mains switch for under $15. http://www.bunnings.com.au/arlec-remote-control-power-outlet-_p4331239. Basically its a self contained mains switch that works via a remote control.

I'm thinking I could hack into the remote control unit, wire it up to the maximite, and this gives me a safe way to switch mains power. The customer can then just plug in a mains powered siren/bell/lamp/whatever into the Arlec switch.
No mains wiring is needed by me or the customer.

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Glenn Edited by Gizmo 2015-10-29

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

Grogster

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Posted: 06:28pm 27 Oct 2015

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I built something very similar, and this is a perfect way to get around your ticket issues.

You could still have the relay, but you would have to have another sparkie wire it in for you. This would be a requirement anyway, due to the distance, but I seem to recall that the Australian regs are quite ridiculous in a lot of ways, if Silicon Chip articles are to be believed.....

EDIT: An example is that more then once I have needed 240v to a panel, and I just install the panel, and say to the sparkie: "Can you give me some juice to that panel there please?" - done. They run some T&E and connect it for me.

I have a feeling that in Australia, it is NOT that simple.Edited by Grogster 2015-10-29

Smoke makes things work. When the smoke gets out, it stops!

TassyJim

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Joined: 07/08/2011
Location: Australia
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Posted: 06:50pm 27 Oct 2015

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How do you think I turn the coffee machine on?

http://www.thebackshed.com/forum/forum_posts.asp?TID=6841&KW=coffee

Jim

VK7JH
MMedit

robert.rozee
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Joined: 31/12/2012
Location: New Zealand
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Posted: 06:51pm 27 Oct 2015

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a solid state relay (SSR) may be a good / reliable / simple option:

http://www.ebay.com/itm/261785486229

just provide the electrician with the SSR bolted into a di-cast metal box that he/she wires up to the bell, and you provide a length of bell wire to run between the MM's output and the SSR's input terminals. if you are really keen, place a barrier in the box between the two ends of the SSR.

cheers,
rob :-)
Edited by robert.rozee 2015-10-29

MicroBlocks

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Joined: 12/05/2012
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Posted: 08:30pm 27 Oct 2015

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I use a SSR to control a heated pad. It is switched of/on every few seconds for hours long without any problem. Also the 3-32VDC inputs help as longer wires can be used with higher voltages. 6v or 12v for (very) long lengths works good.
Edited by MicroBlocks 2015-10-29

Microblocks. Build with logic.

OA47

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Joined: 11/04/2012
Location: Australia
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Posted: 10:16pm 27 Oct 2015

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Just my two bobs worth, could you use a security system siren as it will run on 12volts from your plug-pack and they can make a fair bit of noise.

GM

MicroBlocks

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Posted: 10:46pm 27 Oct 2015

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Or use an mp3 module and hookup an amplifier and loud speaker. :)
Can make different sounds for the different occasions.

I did that once a long time ago with an amusement park. It made announcements like 'train schedules', or warnings (i am not kidding) when animal escapes, etc..
They also used the same speaker system for lost kids, just by using a microphone.
Very flexible and can cater for very different kinds of uses.

Microblocks. Build with logic.

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
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Posted: 12:28am 28 Oct 2015

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With 'workshop' distance being an issue, the remote controlled socket makes perfect sense IMHO.

One thing I have come across with the remote control sockets is that some Transmitters work on resistance on the key-matrix. When you then try 'shorting' the buttons of these type out with a MicroMite then it seems to permanently damage the remote

Anyway, I found one brand (Siemens) that worked well when the Tx switch was shorted out with a 4066 switch (controlled by a MM).
The remote had 4 On & Off buttons as well as a 4-way channel selector switch. Hence with three 4066's I was able to MM control 16 mains devices.

Use this set-up whenever way from the home for the night to trigger lights on and off. Also forms the basis of a reliable Home Automation setup

Gizmo

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Posted: 02:06pm 29 Oct 2015

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Thanks for the feedback and tips.

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

Gizmo

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Posted: 04:58pm 01 Nov 2015

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I bought a Arlec single outlet unit from Bunnings for about $13.

After testing it worked OK, I pulled the remote control unit apart to have a peek. It uses stantard pushbutton switches and runs on a 3.2 volts. When transmitting, the current is about 9mA.

Cool, this makes life easier.

9mA at 3 volts means I can power the transmitter directly off the Maximites 3.3v supply, eliminating the need for batteries. The transmitters push buttons are floating above 0v in a matrix of some sort, so I used a couple of opto couplers driven by the Maximite to switch the transmitter functions, the On and Off buttons.

The transmitter circuit board is mounted over the "sea of holes" on the CG Colour Maximite, with a few short copper wires to hold it in place. I removed a couple of the unused push button switches and used their copper pads as anchor points