12v inverter and Victron battery charger ?

[Ardenfour]

Thanks for all the replies. I have a 240 ring system installed with several sockets, so I thought it would be simple just to connect the inverter at some point in the circuit. How about a flying lead with ax13A plug at each end? Ha, only joking. I very seldom plug in via shore cable. The shore socket connects via a mcb, don't think it's an rcd. I like the idea of a fit and forget changeover switch.
I guess this is a similar wiring issue to a built-in generator...

 

[PaulRainbow]

Thanks for all the replies. I have a 240 ring system installed with several sockets, so I thought it would be simple just to connect the inverter at some point in the circuit. How about a flying lead with ax13A plug at each end? Ha, only joking. I very seldom plug in via shore cable. The shore socket connects via a mcb, don't think it's an rcd. I like the idea of a fit and forget changeover switch.
I guess this is a similar wiring issue to a built-in generator...

If no RCB, or you don't know what you have, draw it out.

Don't mess around or take chances with 240v AC.

What inverter do you have ?

 

[Alex_Blackwood]

If no RCB, or you don't know what you have, draw it out.

Don't mess around or take chances with 240v AC.

What inverter do you have ?

Maybe consult a professional??

 

[PaulRainbow]

Maybe consult a professional??

Always a good option, especially with potentially lethal voltages/currents.

I do tend to avoid the suggestion, or my anti-fan club suggest i'm only here to line my own pocket

 

[jackho]

Do you mean to the input of the battery charger?

You presumably have 240v shore power going to the sockets and to the charger - if you connect the inverter to the existing sockets then it'll also output to the charger, causing the charger to run off the inverter like an ouroboros, flattening the battery as fast as it can.

The simple ways to do this are either:

1. have the shore power connecting only to the battery charger and all the sockets connected to the inverter's output - loads on the sockets discharge the battery, but that's ok because (whist on shore power) the charger is charging at the same time. But then you can never exceed the output of the inverter, and running a heavy load (e.g. fan heater) off the inverter for a sustained period can flatten the batteries as maybe the charger can't keep up (depends on the specification of each, obviously).
2. just split the 240 sockets - have the existing ones supplied by shore power and add one for the inverter's output.

The sophisticated way to do this is with a transfer switch. Victon's combo inverter-chargers have a built-in transfer switch - the shore power goes to its input and it charges the batteries and supplies the mains sockets; shore power is used if available, or inverter if not (or inverter assist if shore power is limited). I have a Multiplus 1600 and it's quite good, but it's not cheap. Looks like Victron also sell separate transfer switches for £200 - £300.

Will try and answer your question by explaining what I am doing similar to you. Given the price of Camping Gaz I intend to install a 12v DC to 240V Inverter to power my boat appliances (when not connected to shore power}. I have on board mains shore powered Quick battery charger to maintain battery bank when shore power is available.
My simple solution is to connect inverter to 12v battery bank and keep 240v separated from shore power. Most inverters have one or more 13a 240v outlets so given the close proximity to battery bank I will take a 13a extension lead from socket and install another 13a socket independent from mains (suitably colour coded etc) at galley.
(Have avoided the technicalities around specification and installation.)

Reluctant to be prescriptive so Ill just describe my proposed system again. My shore power feeds my in board charger on its own circuit and as such is separated from the sockets protected by their own RCB. No conflict with inverter project.
12v from battery bank (via existing fused circuit ) is connected to the inverter input. Output 240v available from inverter sockets. In my case to independent 240v sockets. ( You will have circuit protection depending on inverter spec.)
When connected to shore power batteries charge as normal. - and presumably have inverter powered down.
(For those suggesting cross over switching - some inverters have a UPS 240v input for automatic changeover!!
My suggestion is keep it simple but don't do anything your not fully competent to do.

 

[Ardenfour]

Reluctant to be prescriptive so Ill just describe my proposed system again. My shore power feeds my in board charger on its own circuit and as such is separated from the sockets protected by their own RCB. No conflict with inverter project.
12v from battery bank (via existing fused circuit ) is connected to the inverter input. Output 240v available from inverter sockets. In my case to independent 240v sockets. ( You will have circuit protection depending on inverter spec.)
When connected to shore power batteries charge as normal. - and presumably have inverter powered down.
(For those suggesting cross over switching - some inverters have a UPS 240v input for automatic changeover!!
My suggestion is keep it simple but don't do anything your not fully competent to do.

Thanks, installing a couple of extra sockets for the inverter is probably the way to go. then there are no conflicts.

 

[PaulRainbow]

Reluctant to be prescriptive so Ill just describe my proposed system again. My shore power feeds my in board charger on its own circuit and as such is separated from the sockets protected by their own RCB. No conflict with inverter project.
12v from battery bank (via existing fused circuit ) is connected to the inverter input. Output 240v available from inverter sockets. In my case to independent 240v sockets. ( You will have circuit protection depending on inverter spec.)
When connected to shore power batteries charge as normal. - and presumably have inverter powered down.
(For those suggesting cross over switching - some inverters have a UPS 240v input for automatic changeover!!
My suggestion is keep it simple but don't do anything your not fully competent to do.

Very few inverters offer circuit protection and personal protection (RCD) and virtually all will require Earthing. Suggesting this might be supplied by the inverter is risky.

Automatic changeover is typically a feature of inverter/chargers, where show power is connected to the unit, along with the DC input. AC output will be supplied from shore power or batteries automatically. The exact circumstances will depend on the equipment and how it is configured. This is a complete red Herring in the context of your proposed installation.

Making "permanent" installations with inverters that were not designed to be installed as such, can be a risky undertaking and still needs adequate planning and a proper installation. Just because an inverter has a socket in the end of it does not mean you can just willy-nilly plug cables into it and run them around the boat to fixed sockets. Some of these types of inverters will have overload protection, others not. Some may have a built in RCD type device, most will not. Knowing what yours have might prove tricky if fitting a cheap Ebay inverter with Chinglish instructions.

Whichever inverter you fit and however it is installed, it should be Earthed. That's a connection from the Earthing point (if fitted), or the case, to something that's in contact with the water, typically an anode. It's also important to make sure the the Earth connection at the sockets is Earthed.

 

[PaulRainbow]

Thanks, installing a couple of extra sockets for the inverter is probably the way to go. then there are no conflicts.

Still needs doing correctly, see post #27

You still have not replied to post #22

 

[PaulRainbow]

Sometimes you just wonder why you bother.

 

[jackho]

Very few inverters offer circuit protection and personal protection (RCD) and virtually all will require Earthing. Suggesting this might be supplied by the inverter is risky.

Automatic changeover is typically a feature of inverter/chargers, where show power is connected to the unit, along with the DC input. AC output will be supplied from shore power or batteries automatically. The exact circumstances will depend on the equipment and how it is configured. This is a complete red Herring in the context of your proposed installation.

Making "permanent" installations with inverters that were not designed to be installed as such, can be a risky undertaking and still needs adequate planning and a proper installation. Just because an inverter has a socket in the end of it does not mean you can just willy-nilly plug cables into it and run them around the boat to fixed sockets. Some of these types of inverters will have overload protection, others not. Some may have a built in RCD type device, most will not. Knowing what yours have might prove tricky if fitting a cheap Ebay inverter with Chinglish instructions.

Whichever inverter you fit and however it is installed, it should be Earthed. That's a connection from the Earthing point (if fitted), or the case, to something that's in contact with the water, typically an anode. It's also important to make sure the the Earth connection at the sockets is Earthed.

Your response is the exact reason I stated would stay away from the technical aspects of proposed installation. In my case I only intend to power a single socket for a 800w kettle (to minimise gas usage while under way). In doing so I would hope to be fully in compliance with best practice for this type of installation being aware of the safety and technical requirements.

 

[PaulRainbow]

Your response is the exact reason I stated would stay away from the technical aspects of proposed installation. In my case I only intend to power a single socket for a 800w kettle (to minimise gas usage while under way). In doing so I would hope to be fully in compliance with best practice for this type of installation being aware of the safety and technical requirements.

The problem with this approach is that it can lead people into thinking you can just fit any ole inverter, with a cable going to a socket and it will be safe. This can be far from the truth. Looks like the OP has taken your suggestion at face value and is off to fit a couple of sockets to a length of cable.

I know of inverter that have a socket in the end that have all sorts of built in protection, including from electric shock and don't even need to be Earthed.

On the other hand, there are inverters that off no electric shock protection, need to be earthed and/or don't have any sort of connection between the Earth pin and anything else.

Giving blanket advice for an inverter installation is very risky. As an absolute bare minimum, i'd say make sure the case is Earthed and make sure the Earth pin has continuity to Earth. Check the socket with an RCD tester.

 

[PaulRainbow]

I hate inverter threads, never seem to be able to get the message over, inverters can kill you.

People will describe some diabolical installation and say, "been like it for years and works fine". Houses used to be wired with cloth covered wiring, no RCD and barely a fuse in sight. I remember seeing multi socket adapters for the ceiling light fitting, so you could plug extra kit in etc. It did all work OK, until a fault occurred, then you might find your house burnt down or someone dying of electrocution.

 

[Robih]

I hate inverter threads, never seem to be able to get the message over, inverters can kill you.

People will describe some diabolical installation and say, "been like it for years and works fine". Houses used to be wired with cloth covered wiring, no RCD and barely a fuse in sight. I remember seeing multi socket adapters for the ceiling light fitting, so you could plug extra kit in etc. It did all work OK, until a fault occurred, then you might find your house burnt down or someone dying of electrocution.

Back in 1979 I was working on a farm. I was using a metal cased 240v drill that for reasons unknown suddenly became live. I only survived because there was someone there to unplug it. Back in those days, at least on the farms, the electrical protection systems were woeful. If the fuse blew the normal response was to put a bigger fuse wire in it. No RCD/RCBOs in those days. I’ve had respect for electrical protection systems ever since.

 

[Ardenfour]

Sometimes you just wonder why you bother.



Sorbeeawayn away for a bit. Your advice is very much appreciated ! I'll find out which inverter I have, it's down at the boat.

 

[Ardenfour]

Back in 1979 I was working on a farm. I was using a metal cased 240v drill that for reasons unknown suddenly became live. I only survived because there was someone there to unplug it. Back in those days, at least on the farms, the electrical protection systems were woeful. If the fuse blew the normal response was to put a bigger fuse wire in it. No RCD/RCBOs in those days. I’ve had respect for electrical protection systems ever since.

I remember a '70s government safety film where the drill user had the bare wires jammed in a socket with matchsticks

 

[lustyd]

suggest i'm only here to line my own pocket

If you are you’re very bad at it. I’ve never even seen you offer your services and your website says you generally only work locally!

 

[jackho]

The problem with this approach is that it can lead people into thinking you can just fit any ole inverter, with a cable going to a socket and it will be safe. This can be far from the truth. Looks like the OP has taken your suggestion at face value and is off to fit a couple of sockets to a length of cable.

I know of inverter that have a socket in the end that have all sorts of built in protection, including from electric shock and don't even need to be Earthed.

On the other hand, there are inverters that off no electric shock protection, need to be earthed and/or don't have any sort of connection between the Earth pin and anything else.

Giving blanket advice for an inverter installation is very risky. As an absolute bare minimum, i'd say make sure the case is Earthed and make sure the Earth pin has continuity to Earth. Check the socket with an RCD tester.

I think all the advice has raised awareness of the complexities to this type of installation. That's why I stated I would avoid the technical detail because there are too many variables (even your earthing comments are a technical subject on their own depending earthing points , fault currents clearing times, relating to distance from mains supplies at some marinas ,boat type and existing shore power installation. All too technical to cover on this topic and indeed on any forum. If in doubt check out compliance standards with suitably qualified 18th Edition Electrical Regs. competent person.

 

[Daverw]

I’m not sure 18th edition would be of any help as either way it does not cover anything to do with boats

 

[PaulRainbow]

I think all the advice has raised awareness of the complexities to this type of installation. That's why I stated I would avoid the technical detail because there are too many variables (even your earthing comments are a technical subject on their own depending earthing points , fault currents clearing times, relating to distance from mains supplies at some marinas ,boat type and existing shore power installation. All too technical to cover on this topic and indeed on any forum. If in doubt check out compliance standards with suitably qualified 18th Edition Electrical Regs. competent person.

This is just a total load of nonsense.

18th Edition regs do not come into it. If it was a new build it would be covered by an ISO, which i just happen to have. As it's not a new build, it is not regulated at all, although any half decent marine electrician would follow the ISO and best practice.

Your comments about Earthing are just gobbledygook. The inverter should be connected to the boats PE system, which in turn should be connected to the water, via the hull of a metal boat, a ground plane, an anode etc. Not rocket science if one knows how to do it, or if one is prepared to listen, which you clearly are not prepared to do.

 

[Alex_Blackwood]

I think all the advice has raised awareness of the complexities to this type of installation. That's why I stated I would avoid the technical detail because there are too many variables (even your earthing comments are a technical subject on their own depending earthing points , fault currents clearing times, relating to distance from mains supplies at some marinas ,boat type and existing shore power installation. All too technical to cover on this topic and indeed on any forum. If in doubt check out compliance standards with suitably qualified 18th Edition Electrical Regs. competent person.

18th Edition regs do not come into it. If it was a new build it would be covered by an ISO, which i just happen to have. As it's not a new build, it is not regulated at all, although any half decent marine electrician would follow the ISO and best practice. Your comments about Earthing are just gobbledygook. The inverter should be connected to the boats PE system, which in turn should be connected to the water, via the hull of a metal boat, a ground plane, an anode etc. Not rocket science if one knows how to do it, or if one is prepared to listen, which you clearly are not prepared to do.

Even if the 18th edition applied to boats. I think you will find that the only mention of inverters is in relation to UPS units and safety supplies for medical facilities. Even then it is just a mention that inverters should comply with HTM 06-01. which only tells you what the inverter should be capable off. Nothing about stand alone inverters or how they should be installed.
I say that having just trawled through a copy of the said documents.
I would have thought that as far as competent persons were concerned I would take Pauls advice on fitting. There are, as Paul has said, many variations of inverter. some may not require earthing and others do. There are various possible configurations of internal wiring of the inverter power supply. You need to know what you are dealing with and understand all the implications.
I find that discussions on this forum regarding electrical matters, especially 240 volt ac, are fraught with danger. In many instances there are replies that are based on a little knowledge and even less experience. The fact that someone has to ask almost always implies that they don't know what they are doing and I am in many cases reluctant to offer advice other than to consult a professional.