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muddy0409 Senior Member Joined: 15/06/2011 Location: AustraliaPosts: 125
Posted: 08:28pm 15 Dec 2014
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We have a 5kW solar system.
I would have thought that this would take over if the grid went down, as it did for 3 hours today?
I figure the inverter gets a sync waveform from the mains to make it run? So if this is the case, could a 50Hz signal be injected into the inverter by some other means until the grid comes back?
I realise there would need to be some smart switching and timing for the swapover of sync, but is it feasible?Don't poo poo conspiracy theories.
Remember that everything ever discovered started somewhere as a theory.
M Del Senior Member Joined: 09/04/2012 Location: AustraliaPosts: 155
Posted: 10:22pm 15 Dec 2014
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Hi muddy
It will be a bit more complicated than a 50Hz signal and some switching.
Feasible yes, considering it myself.
Min requirements for legality in my area, an inverter charger, some batteries, isolation switching, etc done by ticketed sparky/equivalent. The switching and sync as you say can be the stumbling block as your distributor will want triple assurances that it will isolate and not burn the linesmen doing repairs.
Some work can be done yourself, but most will want to sell you a kit.
This would be minimal, others more knowledgeable will be able to give more information. Mark
powerednut Senior Member Joined: 09/12/2009 Location: AustraliaPosts: 221
Posted: 12:35am 16 Dec 2014
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you need to isolate it from the grid if your going to do that. The reason they don't keep the house powered is for saftey - be irritating for the linesman if they got shocked when everything should be safely off.
muddy0409 Senior Member Joined: 15/06/2011 Location: AustraliaPosts: 125
Posted: 04:44pm 16 Dec 2014
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Rightio, that sorta answers my question...Too damn hard, expensive and bureucratic for my liking and abilities.
I did have a thought some time ago about the home lighting. It goes something like this.....
A 12v charger on a dirty big battery.
Remove the "lights" cable from the fusebox. This should be a single twin and earth cable.
Connect said cable to the 12v supply & battery.
Replace all my 240 v globes with 12v leds. Using the existing fittings, switches, cable etc.
Sounds feasible to me. I have a total of 15 light fittings, so if they were fitted with 5W leds that would be less than 100w total, so well within cable rating. All the fittings have a large metal body to make a good heatsink for the leds.
What do you reckon?
Don't poo poo conspiracy theories.
Remember that everything ever discovered started somewhere as a theory.
M Del Senior Member Joined: 09/04/2012 Location: AustraliaPosts: 155
Posted: 05:16pm 16 Dec 2014
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Look at a trailer with a couple of panels, regulator, batteries and a smallish inverter to plug in when is down.
8x5 gal trailer with purpose built box
48v battery, 4x12v or 8x6v
2 or 4 200w24v panels, mounted so they can be collapsed
decent regulator system PL20
2-3000w inverter
heavy duty extension cord and a couple of safety power boards with all the safety cut outs fitted.
power goes out, plug it in.
any one asks, it is for camping (4x4 club etc) and is just parked in your back yard.
cost depends on the quality (and source)of your gear and ability, $2500 & up Mark
davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499
Posted: 09:15am 17 Dec 2014
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Just convert it back to mains before you sell the house, as I suspect there would be compliance issues doing it your way.
Why not just use 230V LED lamps and at least you could put a mains plug on the end of the cable you remove from the switchboard? A 100Watt inverter, especially if you can get away with a modified sinewave one would be quite cheap.
Using 24V (two car batteries) should get you quite a few hours of running time. You have do the maths.
muddy0409 Senior Member Joined: 15/06/2011 Location: AustraliaPosts: 125
Posted: 01:45pm 17 Dec 2014
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Yeah, that's another possibibity I hadn't thought much about.
I have already fitted LED (240) to majority of fittings.
And I do have somewhere a couple of small (I think 300W) inverters laying around somewhere.
Hmmm....All the lighting could run on the inverter(s) permanently. That would save mucking around with plugging and unplugging. And could make rewiring back into fusebox a simpler job too.
Could even do it without any additional solar..
Power point - Battery charger - battery - inverter - lights. This would really be fully automatic changeover with zero lights off time on power fail. Just like the battery in an alarm panel.
.....Definitely worth a bit more looking at.
Don't poo poo conspiracy theories.
Remember that everything ever discovered started somewhere as a theory.
Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.
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