WARNING dangerous inverters

Submitted: Sunday, Sep 26, 2010 at 10:38

ThreadID: 81560 Views:42659 Replies:8 FollowUps:24

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Dotrill

Wish to warn on the dangers of cheap 12 to 240V inverters
Having experienced first hand the tragedy of cheap inverters, and wishing to pass this information on to others. Death of a loved one that could easily be avoided. Unnecessary death is a long lasting tragic event to the family and friends left behind. A caravaners forum deleted this vital information and posted a message it was not true and I was a spammer. I dont joke about matters as serious as this. I am a retired HV electrical engineer.

Issue 1) There is no Australian Standard for inverters
Issue 2) Many cheap inverters are not electrically isolated
Issue 3) Some of the cheap inverters sold as sine wave on ebay are not sine wave
Issue 4) Term used by some on ebay 'pure wave' is meaningless
Issue 5) The caravan, motorhome or camper trailer can be charged with 240V through the battery system because the inverter is not electrically isolated from the 12 to 240V side. This is what caused the death we experienced
Issue 6) Many are not aware but inverters that are not electrically isolated are not to be used in some states in public places.
There are inexpensive inverters in both sine wave and modified square wave that are electrically isolated from the 12V to 240V. Brand that springs to mind for inexpensive units is Jaycar or Powertech brand. In the better quality sine wave units Latronics, Selectronics, Sinergex, Victron. Inverters that are electrically isolated will have the information on the box.
Having experienced the death first hand of a camper from a cheap ebay inverter failing it is the last thing I want others to experience. I have since heard of another recent case in Victoria.
Is your life or the life of a loved one worth the meager saving of buying an item that is not safe. Please consider carefully your electrical purchases. Please check with your friends to see if the inverter they may be using is electrically isolated. I have written to all state authorities to get inverters that are not electrically isolated banned.

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Reply By: Member - Don M- Sunday, Sep 26, 2010 at 10:51

Reply By: oldtrack123 - Sunday, Sep 26, 2010 at 12:12

Reply By: Member - Warwick D (SA) - Sunday, Sep 26, 2010 at 12:31

Reply By: Dotrill - Sunday, Sep 26, 2010 at 13:30

Reply By: Cruiser .- Sunday, Sep 26, 2010 at 14:14

Sunday, Sep 26, 2010 at 14:14

Dotrill

Thanks for the heads up, but can you or anyone please explain how I as a Jo Average user can tell if my Inverter is electrically isolated

Cheers,

Cruiser

AnswerID: 431462

Follow Up By: oldtrack123 - Sunday, Sep 26, 2010 at 14:25

Sunday, Sep 26, 2010 at 14:25

HI Cruiser

Not much use testing with a digital multi meter as the very low current they require to read could simply show a voltage which is not a problem.

Simplest way [BUT not 100% perfect] is to use a low wattage 240v test lamp
WARNING this can be dangerous if not very carefull

TEST between each active pin of the plug to earth pin,or cable to battery earth,
IF it lights up, even dull, get it checked by a competent electrician

Peter

FollowupID: 702227

Follow Up By: oldtrack123 - Sunday, Sep 26, 2010 at 14:30

Sunday, Sep 26, 2010 at 14:30

Hi
You could also look for a rectangle within a rectangle symbol
This indicates double insulation

Peter

FollowupID: 702229

Follow Up By: harryopal - Sunday, Sep 26, 2010 at 21:52

Sunday, Sep 26, 2010 at 21:52

For someone like me who wouldn't know what was watt with his amps or his inverter, jump charger of wattever this kind of information is both alarming and confusing.
I have a Toyota Coaster motor home, recently bought, which has two batteries without and isolator. It has 12 volt interior lighting which is powered from the second battery.
Away from 240 volt power I would like to run my 12 volt, 3 way camper fridge, a laptop, 240 volt x 20 watt flourescent lamp and a laptop. And maybe a fan... either 12 or 240 volt.
What would be the most economical, safe way of doing this. (I have read of people being talked into very expensive inverters way beyond the relatively simply need of the buyer.)
I have tried reading the various posts on electrics and my brain turns to porridge. Now with this latest warning am really not sure which way to turn. So, thanks for the warning and some advice much appreciated.

FollowupID: 702320

Follow Up By: harryopal - Sunday, Sep 26, 2010 at 21:57

Sunday, Sep 26, 2010 at 21:57

For someone like me who wouldn't know what was watt with his amps or his inverter, jump charger or wattever this kind of information is both alarming and confusing.
I have a Toyota Coaster motor home, recently bought, which has two batteries without an isolator. It has 12 volt interior lighting which is powered from the second battery. It also has a 240 volt system properly fitted with safety switches and a plug in for taking power at a caravan park
Away from 240 volt power I would like to run my 12 volt, 3 way camper fridge, 240 volt x 20 watt flourescent lamp and a laptop. And maybe a fan... either 12 or 240 volt.
What would be the most economical, safe way of doing this. (I have read of people being talked into very expensive inverters way beyond the relatively simply need of the buyer.)
I have tried reading the various posts on electrics and my brain turns to porridge. Now with this latest warning am really not sure which way to turn. So, thanks for the warning and I would really appreciate some advice that would cover the use as I have described. Thanks in anticipation of responses.

FollowupID: 702321

Follow Up By: oldtrack123 - Sunday, Sep 26, 2010 at 22:21

Sunday, Sep 26, 2010 at 22:21

Hi Harry

Your 3way camper fridge will drain your battery very quickly when the engine is not running, use it on gas when camped
You can get 12v adaptors that are more efficient than an inverter for charging /running your laptop

Fans are available in 12v

Not sure of the reason you want a 20w 240v flouro but again small work type are available in 12v

I would strongly suggest you give the 12v versions a thought before going to an inverter

If your thought are along the lines of plugging an inverter into your van power inlet socket so you can utilize the van power point,
I will say DO NOT DO IT

You would greatly increase the risk of something going wrong

Peter

FollowupID: 702326

Reply By: Member - Dunworkin (WA) - Sunday, Sep 26, 2010 at 22:31

Sunday, Sep 26, 2010 at 22:31

Please help me, after reading this thread I am very concerned about the inverter that we have, it doesn't have the rectangles (mentioned above) on the box, it doesn't have any warnings on it. I have no idea of watt watt is watt and after finishing reading this post I am totally confused. The inverter that we have comes from Dick Smith and it is 300w. In it's features it claims 'Modified Sine Wave'. The biggest concern for me now is whether it is safe or not as I wouldn't have a clue, we plug it into our cigarette lighter and charge up the camera batteries while we are traveling along, don't think I will be doing that again.

If anyone can tell me if this is one of the bad ones it would be much appreciated.

Cheers

Deanna

Simba, our much missed baby.

Lifetime Member
My Profile Send Message

AnswerID: 431532

Follow Up By: oldtrack123 - Monday, Sep 27, 2010 at 13:37

Monday, Sep 27, 2010 at 13:37

HI Deanna

The best place to start for info on your's being fully isolated is DS
If they do not seem to know what you are talking about ask them to find out & confirm writing.

Re : "The biggest concern for me now is whether it is safe or not as I wouldn't have a clue, we plug it into our cigarette lighter and charge up the camera batteries while we are traveling along, don't think I will be doing that again. ""

If it is fully isolated, charging or using anything within it's watts capacity that only has a 2pin plug is pretty safe

Your will not be able to utilize the 300watts capacity from a cig lighter socket.
Ran continuously at full load will burn out the lighter socket /wiring [draws about 25amps ]

Peter

FollowupID: 702393

Follow Up By: Member - Dunworkin (WA) - Monday, Sep 27, 2010 at 21:21

Monday, Sep 27, 2010 at 21:21

Thanks for your information Peter, I don't like my chances with DS knowing anything from previous experience but will definitely give it a try. I really don't know a thing about electrics apart from when I turn a switch lights go on etc.

Thanks again.

Deanna

Simba, our much missed baby.

Lifetime Member
My Profile Send Message

FollowupID: 702428

Reply By: brushmarx - Monday, Sep 27, 2010 at 10:48

Monday, Sep 27, 2010 at 10:48

I guess I'm not the only one with limited knowledge of inverters, and obviously don't want to experience tragedy through the use of one.
I have an Ebay inverter, and it is not pure Sine Wave.
The instructions suggested an earth strap connected to a metal spike driven into the ground was preferred.
I contacted the seller, and was told that was unnecessary in Australia, and was both impractical and a waste of time.
I need to drag it out of winter storage and check for isolation notices to see if any stickers are visible.
This idea of checking with a 240 volt low wattage bulb sounds feasible, but is the problem a "yes or no" type of testing, or if it tests OK now, can it develop into a potentially lethal power supply from being subjected to corrugations or rough handling?
Cheers
Ian

AnswerID: 431562

Follow Up By: oldtrack123 - Monday, Sep 27, 2010 at 14:00

Monday, Sep 27, 2010 at 14:00

Hi Ian

Your info was correct ."An earth stake is neither required OR recommended" by the AUS standards

If it is the non isolated type then that's it it is already dangerous

Re: "This idea of checking with a 240 volt low wattage bulb sounds feasible, but is the problem a "yes or no" type of testing, or if it tests OK now, can it develop into a potentially lethal power supply from being subjected to corrugations or rough handling?""
s
Yes if the test shows it is NOT the non isolated type then that means no faults @ TIME OF TESTING IN THE INVERTER

The Problem is that the 1st fault which can change the system can occur anywhere in the system.
Wiring Or any appliance may may develop a fault to earth.[frame /chassis ] not terra firma /ground
That fault on its own will not be evident ,but may show up if you connect to a RCD protected supply.

What that fault does IS CHANGE THE SYSTEM TO a non isololated system , the same as in mains supply with an earthed neutral.
The same sorts of accidents can then occur as @ home if you do not have a RCD[safety switch]

Your van RCD if fitted will be inoperable

The point that many seem to make is that a fully isolated inverter is SAFE
.YES it is until a fault as above occurs

The risk may be low but to deny that there is a risk is stupid

NOTHING is fail safe ,even your RCD.

Peter

FollowupID: 702397