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JEWIENEWIE
06-01-2008, 09:38 AM
I go camping for long periods at a time and have a large solar panel and 2 200 amp hour 6v batteries wich i bridge to get 12v. In the past for lighting i was happy with gas lights, kero etc but now have a young one who is mobile and i dont want to deal with the chance of her being burned etc. I would love to be able to use a house hold fluro light when camping. What size inverter do i need, is it easy to install, what can i run off it, and rough price or brand. Any info would be appreciated.
Jewie

finga
06-01-2008, 09:54 AM
A fluoro would be no trouble. A normal 4 footer uses 36watts of power.
So any inverter that's rated over 36W will do the job. A 300W will do it with ease.
They're easy to install as most have a power type point on them to plug the fluoro into.
A 12V lead will be needed to connect to your batteries.
Run time (for equal load) would be dependent on the internal losses of the inverter. Normally the better quality ones have less losses.
Your doing the right thing by the young one. Accidents happen too easily.

Simmo2
06-01-2008, 09:59 AM
Finga's comments are correct however an inverter is quite inefficient, and you also will have 240v hanging around...
Have a think about getting 12v flouro's, much more betterer!

JEWIENEWIE
06-01-2008, 10:12 AM
Most 12v lights i have seen or used have been pretty poor on the bright side of things, hence me wanting the inverter. But now my fears have gone from her being burned to me being electrocuted!!! i always seem to get some rain when i go camping???
Jewie

Grand_Marlin
06-01-2008, 11:29 AM
All schools of thought are correct here.

You can put an earth stake in for your inverter and then run a safety switch (RCD) which will protect against electrocution.

The inverters are inefficient ... I use one at work (800w) for running drills / grinders, as I work mobile, and after a couple of hours running a grinder / drill it certainly draws the battery right down.
There wouldnt be all that much "run time", especially if you were running a few fluoros.
I would guesstimate a number of hours, but certainly not days.
But, in saying that, the smaller the inverter and the less appliances you run, the better it will last (obviously)

Have you looked at 12v L.E.D technology? Maybe make your own lightboard?
They also make some pretty good LED work lights that mechanics use.
Not as good as 240V, but if you are worried about safety then there is going to be a compromise.

The inverters are safe, but should be treated as any other 240v appliance would be treated - and especially keep it dry.

I got mine from Dick Smith and cant fault it (5 years service so far and it cost me $450)
Springers Low Voltage also have a good range of them in all wattage outputs.

You will also find there are two types ... pure seine wave and modified seine wave.
Pure seine wave is needed for delicate things like computers and mobile phone rechargers... they are also 2 - 3 times the price of modified seine wave.

Modified seine wave is ideal for power tools, lights, microwaves, tv's etc etc.

Modified is what you want.

The dick smith one I got came with heavy duty cables and alligator clamps that connect straight to the battery.

Others that I have installed need to have a power wire run to them, or have power wire supplied but with no clamps / terminal connections.
Still pretty easy to sort out.

Also remember - you get what you pay for.

Cheers

Pete

JEWIENEWIE
06-01-2008, 01:00 PM
thanks for the valuable input Grand_Marlin. My idea was to fully charge the batteries before i leave, only use them for lights of a night time, then recharge them via the solar panel through the days. I took them away last year and i didnt run out of power at all and i was using 12v lithts, charging mobiles, and the 12v shower for a treat. But dont like the 12v light side of things. Been using them for a while and want better light, hence me looking for info on inverters.
Is it simpler enough to wire up the fluro?
Jewie

Grand_Marlin
06-01-2008, 01:41 PM
By all means, go for it ... use the inverter - I do and find it brilliant.

The inverters all have standard powerpoint sockets on them for plugging in any appliance.

If you get the fluoros and they dont have a plug (most probably wont) then get a reputable sparkie to wire a plug on for you.

Finga is the man for the job ;)

Cheers

Pete

Feral
06-01-2008, 01:53 PM
SOme smaller inverters do not have any "technology" built into them, so draw a fair amount of power whether anything is plugged in or not.

This can be an advantage or a disadvantage. Definately a disadvantage if your running mobile phone or laptop computer or game console chargers, and sometime they dont draw enough power, and the inverter will auto switch off.

However if your setting up with leads and switches, and have switches for the lights etc, you can sometimes forget to disconnect the inverter, so the auto off feature is a bonus.

TheRealAndy
06-01-2008, 06:40 PM
Buy a 12V ballast for a standard fluro batten. Oatley electronics sell them i think. someone here mentioned a website the otherday that specialises in 12v stuff, (see thread about neons) and they sold them too.

oldboot
06-01-2008, 11:12 PM
I would agree that using a 240 volt inverter for powering only a fluro isnt the best way to go.

A good quality high frequency fluro "balast" ( inverter) will be more efficeint and should give better light output than running on 240V mains.

An untethered 240 volt supply can be a dangerous thing.......hence 240 volt inverters have been specificly named in legeslation as being illegal on construction sites in QLD.

Better still and more efficient is LED technology...... LED strips are the go.

check out jaycar amongst others

There is also a growing number of camping specific LED products out there that are getting more economical by the month.

cheers

PinHead
07-01-2008, 05:02 AM
I would use a small generator..no problems then..as long as you have fuel you have light...new ones are now reasonably quiet andl ight and compact.

finga
07-01-2008, 06:57 AM
An untethered 240 volt supply can be a dangerous thing.......hence 240 volt inverters have been specificly named in legeslation as being illegal on construction sites in QLD.

cheers
That's because no bugger does what is recommended to do. That is use an earth stake and ELCB unit. (If your wanting good protection go a 10mA instead of the normal 30mA ELCB. They'll trip if you look at them sideways)
The same applies to generators.
How many guys use an earth stake with the gene??
How many people use inverters in their homes, 4WD, camper vans or trailers etc etc and never had an issue when they do the right thing??
Tons do. Virtually every bugger with a solar panel uses an inverter.
Set the thing up correctly and there is not a worry in regards to electrocution.

A lot of control gear for motor drives uses inverter technology ie infinite speed controls on machines for one. Do they want to ban those as well.
Gees when are the law makers going to wake up. Ban the dope not the appliance that is as safe as can be if and when used correctly.

They should ban extension leads instead.

Grand_Marlin
07-01-2008, 12:06 PM
Keep in mind that a construction site (construction workplace) is where building / construction work with a value greater than $80,000 is done ... any other work site is exempt.

There was an information paper put out in 1994 that stated the inverters were banned from construction sites, pending a review of the Australian Standard.

AS 4763 (2006) apparantly addresses the problem and gives recommendations for RCD protected inverters to be used in a construction workplace.

I haven't yet read the standard to know what the final outcome was.

Also, apart from the information paper, I have not seen anywhere in the Electrical Act or Regulations where they have stated that the inverters are banned from construction workplaces.

I am happy to have this pointed out to me, as it is often difficult to find info in the regs.

Cheers

Pete

finga
07-01-2008, 02:04 PM
Apparently inverters can be used on construction sites as AS 4763 has this in the opening stanza and is a direct cut and paste from AS 4763.

1 Scope
This Interim Standard applies to single-phase or polyphase, air-cooled (natural or forced)
portable inverters having a rated supply voltage not exceeding 60 V ripple-free d.c. and an
alternating current (a.c.) output where:
- the rated output does not exceed 3 kVA;
- the rated output voltage is within the range 50 – 500 V a.c;
- the rated frequency of the output is within the range 40 – 100 Hz.
NOTE 1 Portable inverters may be provided with facilities for fixing to a surface.
This Interim Standard is applicable to inverters of the following types :
− isolated inverters
− equipotentialy bonded inverters
− RCD protected inverters
These inverters are for
− household and similar use,
− use on construction sites, or
− providing an independent supply to electrical installations in buildings, vehicles, caravans,
boats and the like.

The Standards does not however describe what type to use in what environment or how to install one.
It focuses on the physical construction of the inverter not how to use one of the buggers.

Grand_Marlin
07-01-2008, 02:17 PM
Thanks Finga, it looks like they did change it for the betterment of all man kind ;D

So there you go, if it is an inverter you want, look around for a modified seine wave, RCD protected model.

Cheers

Pete

finga
07-01-2008, 02:23 PM
Thanks Finga, it looks like they did change it for the betterment of all man kind ;D

So there you go, if it is an inverter you want, look around for a modified seine wave, RCD protected model.

Cheers

Pete
Or get one of those 10mA plug in safety switch on a lead and plug it into the inverter and get an earth stake (a steel rod will do. Copper coated is best or stainless will suffice) to bung in the ground so the case of the inverter and the earth terminal of the inverter is bonded t earth potential.

Personally I'd be using the inverter and the fluoro. especially considering the size of the batteries you have already.

Plug and lead on the fluoro is easy.

Pete if there was anything interesting in that standard I'd copy it and post it to you but the isn't so I won't. :D

oldboot
07-01-2008, 09:18 PM
Actualy you will probaly find that the inverter ban is in the workplace health and safety act.

No I have never see anybody run an inverter or a generator with an earth stake.


The act will not even allow for this because unless the earth stake was driven and tested and a certificate of test issued by a licenced electrician it can not possibly be considered safe or effective.

The ban is specificlay on portable inverters.

Inverters within other devices are not effected

One of my concerns is that there is a false perception that earth leakage devices provide complete protection against electrocution.

They do nothing of the sort. they only protect against shock between earth and active.
They will do nothing to protect against a short between active an neutral.

If there is a dodgy double insulated device ( most power tools) connected to an unearthed inverter or generator, even if it did have an ELCB there would be no protection whatsoever.

If the earth stake is driven ito dry ground or sand it is likly that the earth resistance will be unsatisfactory.

Anybody that has had anything to do with getting an earth on stradie, frasier or moreton in certain areas will understand.

by the time you buy a fluro fitting that is fit for portable use and an inverter you could have baught a good fist full of LED strip lighting.

One other option is low watage halogens........like 20 watt dicroics or emergency light fittings.

those who are using inverters in homes & the like are a completely different story.
many of them will be wired into complying instalations.
I know how many of the building industry types would use inverters.... mostly it would be because they were in a hurry and couldnt be bothered running out an extension cord.

On the subject of dodgy extension cords..... have a look at the penalties in the current electrical safety act..........a dodgy extension cord will make the government a lot of money.
Being the owner of a dodgy extension cord on a construction site....75 penalty units
being the person using the dodgy extension cord ....75 penalty units
using having an untaged item on a site.... 75 penalty units
allowing either of of the above on a site... 75 penalty units

once you get round all the different ofences..... 1 dodgy extension cord could amout to 8 or ten ofences, for various different people involved if they wanted to go there.


I personly would have no problems using portable unverters myself.... but in the hands of many I have met they are portable boxes of death that run on 12 volts.

cheers

cheers

Simmo2
07-01-2008, 09:44 PM
Good point Oldboot!
I was gonna mention earlier today, that an earthstake, although a possible lifesaver, is useless if it doesnt actually do anything in regard to potential differance. May as well bash a stick into the ground. And who has a mega at hand to test that stick?!!

In a 'temporary home/camping' environment, I would not have 240ac sitting around the ground in the form of leads etc. (I run an invertor too, in the truck, if 240 is needed, then so be it!)
12v dc is fine for most applications. If lumens is your problem, then look at some led technology such as 'cree' or 'luxeon' etc etc...

What we do at camp is have 4 12v flouros, one big one over the camp area, one inside the tent, one over the stove and one over the fridge. (There is also a little one inside the shower tent if we decide to set that up.)

Each and everyone can be turned on or off at will. (Fridge one stays on all night!)

For us, we dont want to light up the whole neighbourhood, just have enough light to do what we need to do and still be able to relax....

Grand_Marlin
08-01-2008, 07:19 AM
G'day Old Boot,

Thanks for that.

The ban isnt / wasnt in the WHS Act either.

The WHS Act gives the framework and the regulations give the "rules"
The Act or Regs then call up any other legislation (other acts, codes of practice, AS / NZ Standards etc) to support it... therefore the ban would most probably have appeared in the regs (which it didnt), or there has been some suboordinate legislation or ministerial notice that has banned them.

WHS Act (section 3A) calls up the Electrical Safety Act and gives it precedence over the WHS Act.
The WHS Act doesnt have a section on electrical at all.

Can I ask where you got your info on the penalties?
As far as I am aware, the offences you mention carry a 4 penalty point fine for and individual and 8 penalty point for a company.

1 penalty point = $75

Maybe there have been changes I dont know about?

Cheers

Pete

finga
08-01-2008, 09:14 AM
Maybe we all should just use candles but they can start a fire.

You could use 12v and l.e.d.s and all that but you could trip over the lead or fall off the ladder when you place the leads above tripping height.
You could use a torch but it could fall in your eye and blind you.
Everything has risks.

Use any appliance with due diligence and there should never be a problem.
What's the statistics on electrical accidents caused by inverters??
What's the statistics on shark attacks?? What's the statistics of people with major burns from 12V.

Give a moron a paddle pop stick and he could blind himself.
Bungie is not a brainless twit so it's unfair to say don't use an inverter.
If they were so dangerous they would not be on the market.

As a side note earth resistance is not measured with a megger. An accurate multi-meter or a dedicated earth resistance meter is the go. Mine cost about $1500
Meggers are notoriously inaccurate for reading low resistances needed to be measured when undergoing an earth resistance test of an earth stake.
Megger meters are used for measuring insulation resistances (millions of ohms) not earth resistance (1-100ohms).
Meggers also usually pump out either 250, 500 or 100 Volts on the megohm scale. Definitely low current but still high voltage just like a teeny weeny electric fence. The buggers can hurt.
Personally I'd be more concerned about the whappo from using the megger incorrectly then getting electrocuted by using an inverter complete with ELCB/RCD unit.

A ELCB/RCD unit does not only protect you active-earth faults. They protect you from neutral-earth faults

"If there is a dodgy double insulated device ( most power tools) connected to an unearthed inverter or generator, even if it did have an ELCB there would be no protection whatsoever."
I initially thought well that's wrong so I had to get my brain going about it.
That statement is true but you are protected automatically with the double insulation built into the appliance if there is an internal fault.
This statement also holds true for double insulated appliances the home.

That statement is totally untrue if there's exposed active wires which you happen to hold, touch brush etc and you are also touching an appliance that is earthed to the gene or inverter and if the ELCB on the gene or inverter has been installed correctly.
If the double insulated appliance is working and you touch, brush etc an active wire whilst the appliance is working then an out of balance should appear and the ELCB/RCD should trip.
If your unlucky enough to grab both conductors enough to be the circuit of least resistance across both the conductors then your cactus.

But in this case Jewy was only wanting a fluoro light which are generally needed to be earthed so in this case using a fluoro in the camp site would be safer then using a hair dryer in the bathroom.

A fact, that I admit is new to me, they recommend not to earth the gene.
We were always taught to earth the gene during my apprenticeship with the supply authority.
Internal wiring of the gene must comply with Figure 1 in AS 2799-1989 for the ELCB/RCD to correctly operate though.
An approved ELCB/RCD unit detects an imbalance between the active and the neutral conductors not the current going through the earth wire/medium. Basically that means what goes out must come back and if it didn't come back then something's buggered up.
The ELCB/RCD is rated on the amount of imbalance between the active and neutral conductors it will detect before tripping...not the amount of current going through the ground or earth potential. (that's different to the current going through the earth wire)
That's why they also call a safety switch or ELCB a RCD unit...residual current device.

I've never installed an ELCB/RCD and connected an earth wire for the unit to use as a reference.

Yes a dedicated ELCB/RCD unit will not protect an over current situation in active neutral fault. That's the job of the fuse or CB or better still the combination ELCB/RCD, CB unit.


If Bungie wants to use a fluoro then it would be earthed and have an active and a neutral conductor.
The conductors will be continuous from the light through the lead through he ELCB unit to the inverter.
If there's a problem the ELCB unit is not relying on the earth resistance (or lack of it) through the ground. It is relying on the imbalance between the active and neutral conductors.

The earth stake can be added protection. If you don't want to use it then that's that. So be it.

Aahh bugger it all. I reckon we all should just go to sleep when it gets dark and save all the troubles.

JEWIENEWIE
08-01-2008, 09:42 AM
Sounds alot bloody easier and cheaper to mate.
Jewie

Grand_Marlin
08-01-2008, 10:48 AM
Aahh bugger it all. I reckon we all should just go to sleep when it gets dark and save all the troubles.

Dont be so STUPID Finga, statistics say a lot of people die in their sleep ... therefore it is way to dangerous to do this ;D


Cheers

Pete