John Wr Posted March 8, 2009 Share Posted March 8, 2009 Have used an inverter now for some years,but always I think with double insulated appliances eg lights, chargers and TV. I am left wondering though what are the consequences of using an inverter with an appliance that needs an earth connection and if there is a failure in the device. If the consequences are as dire as I think, is there some practical action which could be taken or should such appliances only be used with a big note of caution. Any thoughts or am I missing something obvious? Cheers John. Quote Link to comment Share on other sites More sharing options...
Elldisrod Posted March 8, 2009 Share Posted March 8, 2009 (edited) Have used an inverter now for some years,but always I think with double insulated appliances eg lights, chargers and TV. I am left wondering though what are the consequences of using an inverter with an appliance that needs an earth connection and if there is a failure in the device. If the consequences are as dire as I think, is there some practical action which could be taken or should such appliances only be used with a big note of caution. Any thoughts or am I missing something obvious? Cheers John. So long as the appliance is correctly wired in the plug, then the protection afforded by the earth connection in the inverter will be the same as it would be if the appliance were connected to the public supply, so any perceived danger would also be the same as if the appliance was connected to the public supply . So the risks of using an inverter are no different to connecting to the mains Edited March 8, 2009 by Elldisrod Quote Link to comment Share on other sites More sharing options...
RogerL Posted March 8, 2009 Share Posted March 8, 2009 But the inverter itself isn't connected to earth - the 12v go to battery positive and negative - the mains side goes to the appliance - if the appliance develops a fault, it's earth connection doesn't go anywhere. Quote Link to comment Share on other sites More sharing options...
fred Posted March 8, 2009 Share Posted March 8, 2009 But the inverter itself isn't connected to earth - the 12v go to battery positive and negative - the mains side goes to the appliance - if the appliance develops a fault, it's earth connection doesn't go anywhere. Until you touch it or the appliance plugged in then it's earthed. Doesn't the same apply to a generator shouldn't they be earthed as well with a spike driven into the ground? Can't remember one being used like that though Quote Link to comment Share on other sites More sharing options...
RADIOTWO Posted March 8, 2009 Share Posted March 8, 2009 Have used an inverter now for some years,but always I think with double insulated appliances eg lights, chargers and TV. I am left wondering though what are the consequences of using an inverter with an appliance that needs an earth connection and if there is a failure in the device. If the consequences are as dire as I think, is there some practical action which could be taken or should such appliances only be used with a big note of caution. Any thoughts or am I missing something obvious? Cheers John. I think you will find that with a Inverter or a Generator that both the earth and Neutral are at the same potential (ie they are connected together) The only way to get a good earth is to knock a 3/4ft copper rod into the ground and 6/10mm of cable to connect to the inverter etc Radiotwo Quote Steve - Land Cruiser Amazon Auto + Pageant Series 5 Champagne The match between car and caravan is perfect in accordance with a mix of European standards. However, according to the British Towing Code the percentage (loaded caravan / kerbweight tow car) is 49%. Link to comment Share on other sites More sharing options...
Paul styper Posted March 8, 2009 Share Posted March 8, 2009 There's no need to worry about an earth as it's isolated through the step up transformer. It's similar to an isolating transformer used in radio and electrical repair workshops to minimise the risk of shock. Quote Link to comment Share on other sites More sharing options...
Wonky Posted March 8, 2009 Share Posted March 8, 2009 I'm not an electrician, but my limited knowledge tells me there is no danger of a shock unless you short out both sides (i. e. live & neutral). In household mains, the neutral has a path through the earth (connected back in the sub stations) which is why you can get a shock that way. I am sure someone with a better knowledge will confirm this (or tell me I am talking rubbish ). MW Quote Discovery D3 HSE + Coachman VIP 575/4 2016 www.pennplanning.co.uk Link to comment Share on other sites More sharing options...
beejay Posted March 8, 2009 Share Posted March 8, 2009 The Aldi/Lidl inverters instructions state it must be connected to earth and an earth connection point is fitted. Quote Link to comment Share on other sites More sharing options...
Elldisrod Posted March 9, 2009 Share Posted March 9, 2009 To answer one or two points made above, The inverter is a stand alone device, it has its own internal earth connection, so it no way relies on any external earth path for safety, The use of an earth rod will add nothing to enhance safety if the inverter is connected directly to an appliance, New regulations now require EXTERNAL generators / inverters to have an earth rod connected to the generator/ inverter, and also an earth rod connected to the main earth terminal in the portable building ( caravan ) There are many designs of inverter / generator with various methods of deriving the earth connection I have a 300w inverter, just for laptop use, and in this the output is centre tapped, so the output is 120v above and below earth, I also have an early Honda generator with a similar system, so it is not safe to assume all generators and inverters are the same, The simple answer is to read and digest the instructions and follow any safety notes to the letter Even the output from an inverter can be deadly, it takes as little as a 50v shock to stop the heart . Quote Link to comment Share on other sites More sharing options...
geriatric Posted June 6, 2009 Share Posted June 6, 2009 To answer one or two points made above, The inverter is a stand alone device, it has its own internal earth connection, so it no way relies on any external earth path for safety, The use of an earth rod will add nothing to enhance safety if the inverter is connected directly to an appliance, New regulations now require EXTERNAL generators / inverters to have an earth rod connected to the generator/ inverter, and also an earth rod connected to the main earth terminal in the portable building ( caravan ) There are many designs of inverter / generator with various methods of deriving the earth connection I have a 300w inverter, just for laptop use, and in this the output is centre tapped, so the output is 120v above and below earth, I also have an early Honda generator with a similar system, so it is not safe to assume all generators and inverters are the same, The simple answer is to read and digest the instructions and follow any safety notes to the letter Even the output from an inverter can be deadly, it takes as little as a 50v shock to stop the heart . And on the subject of safety don't interfere with anything electrical be it 12 volt or 230, ac or dc. All can kill given the wrong set of circumstances. If you have been trained then by all means do your own thing, if not, leave well alone. Quote Link to comment Share on other sites More sharing options...
dave11a Posted June 6, 2009 Share Posted June 6, 2009 I bought one a couple of years ago and the instructions were very vauge so I rang the company and spoke to one of thier Electrical engineers who told me that for safety the Inverter should be earthed but a connection to the caravan chasis would be sufficient but an earth rod would be preferable but not essential Dave. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.