Hi Vic

Here is how I see it

The mains 240v setup is ok has RCD & overload CB

The fridge is 240v /12v & I assume compressor type,if so when OFF mains best ran on 12v [more efficient than using an inverter]

Others have sorted out the "get power"

IMHO, get rid of it I see little purpose or use for it

That leaves the large inverter.

It is not permanently connected into the 240v system, so no problem there

Unfortunately with the lack of details we do not know if it is :

[1]MSW or PSW, so its suitabilty to power all 240v appliances with out problems is unkown

Observing how appliances behave compared to being on mains 240v can be guide

Watch for overheating , strange sounds,etc

[2]Unable to determine if it is fully isolated [usually indicated by a small square within a square symbol] or non isolated

[a]an electrician could determine to a resonable extent if it is non isolated type

It is harder to prove they are truely fully isolated in accordance with the standards

If it is a non isolated type, I would toss it .THEY ARE POTENTIAL DEATH TRAPS 

 In either case use with great care & only connect ONE class 1 devise [3pin plug]AT any time

You may with a higher level of safety connect more than one Class 2 devices [2 pin plug]

[3]UNDER NO CIRCUMSTANCES. try to connect it to the existing 240v system as your existing RCD will not be functional

Battery charger :THAT  charger is little more than a maintenance charger

It will take days to recharge a large amphr battery such as would be needed if you used the large inverter on a regular basis 

Even if permanently connected it would run little more than one decent 12v light. Certainly could not keep up to the fridge

Two question what size aux battery do you have make & model of fridge?? 

Peter

Thanks for the feedback OT, Troopy and Dorian.

I will get some more detail on the aux battery size, but it is 38 degrees outside at the moment so am staying indoors for awhile.   I think the 12V/240V fridge is an Engel and about 30 or 50 litres.   The microwave is only 240V as far as I am aware.

When we first got this recently, the interior campervan lights would not work on 12V.   However after plugging the charger into 240V, the indicator lights showed the aux battery was flat (after I plugged it into the normal 240V socket in the van) and was charging.   I am pretty sure I only had it on charge for probably 5-6 hours and the green light showed it was then fully charged.

Disconneted the outside 240V supply and all the interior lights now working on 12V, so assume the aux charged up ok. 

As it would be highly unlikely we would use the two inverter items and possible danger etc, we may remove them altogether, also make for less weight.    Can this be done by an auto electrician or does it need to be done by a normal electrician?

Thanks

Vic

Hi Vic

Nothing complicated in removing the inverters they are not 240v hard wired

Simply a matter of carefully diconnecting them from the battery& pulling them out

You may find your battery is very sick, if it reached full charge from flat in that time

That would indicate it has only about 10 amp hrs capacity

I would be replacing it before I went anywhere.

Make sure you replace with a deep cycle type

Batterries with low capacity due to age or abuse may appear to be fully charged to the charger as they can reach the required voltage, but can have almost zero capacity

 The microwave , no doubt will be 240v & explains the large inverter 

It would probably be pushing both the inverter & battery to the limit if used @ max heat [depending on it's wattage]

Another good reason for the battery to be sick . 

Peter

Thanks for that Peter, will ask SWMBO if she wants me to remove them.

We like to keep things simple so would only use the microwave or other 240V appliances etc if on 240V at a caravan park.

Can cook on gas at non powered areas etc and have nothing we would miss (TV/AC etc) if not on power.

Without going to check, this is the deep cycle Century Battery it has as the auxillary at the moment, model number 23383, I can see in the fine print it says suitable for 4WD's or RV's.  

Hi Vic

If you cannot see the Amphr rating, take its measurements & go to link below to find out its capacity

Hard to judge  but I think it may be 80Amphr or smaller

Even new that size would not run the fridge for 24hrs without taking it down to a level that would mean short life.

 If you leave mains power you will need some means of charging the battery daily

Peter

Info on Get Power DC/AC converter "Rong Feng" E08 VDE Euopean plug, (red positive lead also has inline fuse at auxillary battery connection.)

See these links for plug details;

http://www.allproducts.com/manufacture9/rongfeng/showroom1.html

http://www.allproducts.com/manufacture9/rongfeng/e08.html

Hi Peter,

Info on Auxillary Battery Century C27M Deep Cycle, same battery and size as that shown in picture on link below, mine also had the words "Deep Cycle" on the top;

http://www.centurybatteries.com.au/search/index.php/batteries/ID-211 

(some general info on leads attached to my auxillary battery, has an inline fuse on the red (positive) lead from the Get Power, no info shown on fuse size, flat pin, also round inline fuses on separate leads showing "10amp light" and "20amp Fridge" )

(some general info on the fridge/freezer cabinet, it is an Engel and interior is approx 40cm wide, x 40cm high and about 40cm deep.  I can see no model markings anywhere including inside.  I suspect it may be what they call a 47litre model?  There is a manual for it that is for models SRBD-543D, SRT-568D, SRBT- 565D, SRT- 5108D and SRBT-5108D, but no info on which one of those it is suspect it may be the first one SRBD-543D but cannot find anything on that model on google.  )

Hi Vic

The Battery is what is generally called a hybrid ,deep cycle & starter battery 

Not Perfect for either but normally give good service

Orignal, as new capacity, 115amphrs

That size @ full capacity & no other energy source would run the Engel for a max of 24hrs & have a reasonable life

But you do have other 12v power requirements so I doubt you would get even 24hrs

 It would need to be fully recharged before futher use

Any compressor  fridge requires substantial battery  capacity or alternative sources of energy [solar ,generator]  when away from mains power.

That little charger would be hard pushed to recharge in much less than 36hrs just what the fridge has used

Good to see that All the pos lines have been fused @ the battery

Peter

Thanks Peter,

The only other 12V requirement other than the fridge would be lighting when not on 240V outside power, they are not LED (haven't taken the opaque covers off the two but suspect not) and one is a small fleuro tube. 

Appreciate the advice,

Thanks

Vic

Thanks for the feedback Dorian, you may well be right with the size, on my other van it is a Waeco 80 litre and there is not a huge difference between them.

For information, I have now removed both inverters, dam hot out there so have not "tested" the remaining electrics yet, I have decided to keep the 240V battery charger on the bench top.   The inside lights are working ok on 12 volts but I want to check the van is starting ok, the fridge works and the battery charger, tomorrows job.

I removed the main leads of both batteries from the Neg and Pos terminals and my only concern now is if there may have been any "bridging" leads on the battery connected with them I am not aware of.   Inspection of what's left appears that all that is needed is wired ok and hopefully will work when I test it.

For info,  once I removed the large inverter I could see more information on a sticker inside the fan grill at the rear, the is in addition to the Power Inverter A1700W 12V and model 021440 E13 I could see on the outside case.

The make is a Hong Sheng, made in Taiwan, Model A6025S12S DC 12V 0.25 Amp (I don't know why the inside model number is different from the outside casing, perhaps they (the outer and inner) both have different model numbers).   There is a date stamped on the sticker which is a day and month in 2008 so seems to be not very old.  FYI,

Thanks

Vic   

dorian wrote:

---

!}another thread you claimed that isolated 240V/110V transformers were unsafe,

[2]while in this thread you are saying that non-isolated 12VDC-240VAC inverters are deathtraps. ISTM that your statements are inconsistent.

[2]Furthermore, my understanding is that inverters are inherently isolated (because they use a transformer to step up the voltage). So my question is, what makes a non-isolated inverter non-isolated?

[3]The other claim that I'm finding hard to accept is your concern regarding the potential differences between the AC outputs of two different inverters. AFAICS, a 480VAC potential difference is only a hazard if the user sticks his fingers in both GPOs, in which case the whole thing must be seen as a furphy. Or is there some other, less improbable scenario that you can see?

[4]In any case, there is no way to wire two inverters so as to avoid the above scenario. This is because each inverter has its own 50Hz clock, and these two clocks are not synchronised to each other. This means that the phase difference will vary each time you turn them on. It could be 0 or 180 degrees, or anywhere in between. Furthermore, the phase will drift over time, so the potential difference will vary from 0 to 480VAC while the units are running.

---

Hi Dorian

The statements are not inconsistant if one fully understands the various risk factors in the motor home /van /camper situation

[1] Not only is the use of step down transformers considered potentialyunsafe in THAT situation ,THEY are not permitted under the standard

[2]portable Non isolated inverters are death traps, many serious accidents & some deaths have occurred with their use

They are totally banned from use in the building & constuction industries for that reason

[3] Interesting that you do not know the difference between non isolated & compliant isolated.

Perhaps if you do a little research, you will understand there are distinct differences ,but I will give you a littleclue , 240vside is linked back to the dc neg internally & remembereven 40milliamps can kill

FULLY compliant isolatedinverters have to meet the requirements of double insulation between the DCside & the 240v side

 Non isolated inverters were widely sold up to a few years ago& i would expect are still available via Ebay

[3] like all electrical accidents there is always a probability factor

Two seperate sources  can always havethe possabilty of cumulative voltages if they have a common connection [as with non isolated inverters]

  If we look at the two in question, considerthesituation where the devise connected to the one with a 2pin plug develops line to frame fault& the user contacts that & the main frame connected to battery neg

I leave you to work that out

[4] Totally agree,the use of multiple inverters,non isolated high risk. fully isolated some low risk

Best to not use  multiple portable inverters

IT may require more than one fault but that fault could be there,unknown ,for a long time , the 2nd fault could be the nasty one

Therisk is like playing russian roulette

Peter

dorian wrote:

---

12VDC @ 0.25A sounds like the rating of the fan.

Here are similar fans:
http://www.vettecorp.com/support/downloads/catalogs/fans/fan_selection_guide/A6025.pdf
http://www.vettecorp.com/support/downloads/catalogs/fans/fan_selection_guide/A6015.pdf

It appears that A6025S12S may be the model number of a 60mm dia x 25mm thick, 12V DC fan.

AFAICT, the first "S" reflects the RPM, whereas the last "S" appears to indicate the bearing type, in this case a sleeve bearing.

---

 Thanks Dorian, I would say you have hit the nail on the head, to me the majority of the techo stuff is way over my head so I don't pick up on clues like that etc.   I'm just glad you techo blokes are members here to help us non techo members out.   Thanks to all of you. 

dorian wrote:

---

My copy of the SAA Wiring Rules dates back to 1991, so I don't know whether it's even worth looking at. I accept that the majority of the rules are safety related, and many issues are the result of quirky accidents whose causes often only come to light after a post mortem. That's why I'm having difficulty understanding the reason behind some of them. Is there anything in the latest SAA Wiring Rules specifically in regard to inverters (other than grid connected types)?

I do understand the concepts of isolation and non-isolation. Some TV repair shops, for example, isolate their workbenches to minimise the risks when working on a live chassis. Even in such cases I can see potential dangers. For example, when one connects an earthed scope lead to an isolated circuit, this results in the whole circuit becoming live once again. In the case of inverters, one could strap the AC earth pin to DC negative, or AC neutral to DC negative, or both neutral and earth to negative. I confess that I don't understand why the designer would want to do that. As for research, I have actually repaired two inverters in my career, one being an older version with a 50Hz iron cored transformer, the other being a relatively modern type with a high frequency ferrite transformer. I don't remember if either was non-isolated.

In fact here is a discussion on the subject:
http://forums.whirlpool.net.au/archive/1543560

And here is a manufacturer's FAQ that actually discusses bonding the neutral conductor to earth:
http://www.enerdrive.com.au/faqs/common-installation-problems

Some people are suggesting that the "square within a square" symbol for Class II appliances doesn't apply to inverters because they are not connected to the mains supply.

I've just answered my own question regarding safety standards:
AS/NZS 4763(Int):2006 Safety of Portable Inverters
AS/NZS 5603:2009 Stand-alone inverters Performance requirements

Unfortunately the above documents are not available for free download. Apparently the relevant standards bodies think that safety information should come at a price.

I also found this thread where you (oldtrack123) appear to have been involved:
http://www.exploroz.com/Forum/Topic/81560/WARNING_dangerous_inverters.aspx?ky=&p=%2fForum%2fDefault.aspx%3fpn%3d4


-- Edited by dorian on Friday 30th of December 2011 07:47:39 AM

---

Hi Dorian

Gee you are putting this old brain to the test [smiling]

There are substantial changes to AS3000 2007 compared to1991,particularly in regard to safety & earthing

Quirky ?? Are not ALL electrical incidents a result of quirky situations arising except for deliberate actions knowing the risk?

Yes, th,e Standards do respond to past & forseeable problems

The 2007 version does have a small section related to isolated supplies

It is this section that seems to have been misinterpreted by many ,as you may see from my post on240v /110v transformers.

That has resulted in serious concerns by a member of the standards committee

However AS 3000 must be read in conjunction with AS/NZS 3001 :2008 where transportable structures are involved[virtualy any vehicle with sleeping accomadation [but includes tents  vans motor homes etc'

This why the general safety recommendation is to have only ONE Class 1 device connected @ any time

I have investigated incidents [one very serious] where shocks were recieved using the old safety packs [isolation transformer].All involved the use of multiple class1 tools with multiple adapters off a single safety pack

Non isolated inverters are the result of many  having a direct path between the Ac & DC side usually via the "Auto turn on" facility &/ or current & voltage sensing for output regulation

Others have leakage via capacitors

An ohmic test will not usually reveal these but a very low wattage  240v[5<10W ]test lamp MAY

The connection to mains or not, is errelavant  as far as safety is concerned

At present, many inverters are fully isolated but may not have the double square symbol

That as you say is just some's opinion

Simply do not buy one unless it is clearly stated to be fully isolated

Those selling them will I am sure emphasis that point.

 The  Standards cover all power over 40v AC no matter what the source

Yes the problem with the standards is you need to be in business [to claim them as a tax deduction] or be quite rich to purchase ALL the cross referenced standards  & have All the detailed requirements

 In most cases it is simply accepted the makers claims that the product does comply with the relevant standards

However in the case of the transformer maker ,in that other tread, the claim was, in part , not correct. While they complied with the requirements for full isolation ,the other claims were incorrect

You will find many forums with posts by me on so called SAFE isolated sources

You may also find some , with my comments,where incidents have occured with isolated sources in motor homes & vans

No one should underestimate the risk when using any AC above 40v ,no matter what the source

I have also had to investigate where a worker was seriously injured  while using a 32v ac hand lamp of an  isolated transformer , supplying other lighting. 

Thes incidents are not fantasy ,they have all happened

There are also many incidents reported from time to time in ESO reports ETC

Iit is now mandatory that ALL portable inverters & generators use in industry [building ,constuction ,mining etc] have Permanently fitted& wired fully operational RCDs

In other word , they are no longer fully isolated ,deliberately,  as such was not fail proof ,with no visual means of knowing,  deaths & accidents occurred 

 A new device, which I expect will gain a significant place in this area is a

"Universal RCD'" which does not require a earthed neutral for operation

Try googling that for more info,

It offers a 2stage protection, full isolation to start but if an earthed neutral situation develops anywhere in the system, it senses that & assumes a conventional RCD operation ' on the next ACTIVE to earth fault, it will trip, quicker than a conventional RCD.

Peter

-- Edited by oldtrack123 on Friday 30th of December 2011 01:30:44 PM

-- Edited by oldtrack123 on Friday 30th of December 2011 05:20:12 PM

dorian wrote:

---

Peter, your latest post has several major cut-and-paste errors.

---

Hi Dorian

I tried 3times to copy & paste those disjointed  now deleted sections  as one section

& they did not paste [well not that I could see]So I gave up a wrote a precis of that section

They are in a Jaycar data sheet, but similar info is available else where 

Peter

I am no computer guru, just self taught.

-- Edited by oldtrack123 on Friday 30th of December 2011 05:38:31 PM

-- Edited by oldtrack123 on Friday 30th of December 2011 05:50:52 PM

oldtrack123 wrote:

---

Hi Vic

The Battery is what is generally called a hybrid ,deep cycle & starter battery 

Not Perfect for either but normally give good service

Orignal, as new capacity, 115amphrs

That size @ full capacity & no other energy source would run the Engel for a max of 24hrs & have a reasonable life

But you do have other 12v power requirements so I doubt you would get even 24hrs

 It would need to be fully recharged before futher use

Any compressor  fridge requires substantial battery  capacity or alternative sources of energy [solar ,generator]  when away from mains power.

That little charger would be hard pushed to recharge in much less than 36hrs just what the fridge has used

Good to see that All the pos lines have been fused @ the battery

Peter

---

Just some feedback Peter, as you said in another post my sized charger could take days to fully recharge the battery from outside 250V source plugged into the van. 

(I was mistake before about the short charge, I had knocked the switch over to 6V and it was showing fully charged, put back on 250V and it was showing charging again.

Has taken 3 days (72 hours) to show the fully charge (green light) almost to the minute.  So many thanks for that advice.  I am now trying out the fridge on 250V, hopefully that will work ok too.