Alternative mains plugs and wall sockets for inverter only use

cygnusv

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Some of the mains sockets that I have on board will still work when there is no marina power connected, through the inverter. I have a change over device that senses when the mains is connected and this disconnects inverter power when the mains is reconnected or re established.

Problem is (potentially) that because all of the sockets and plugs on board are the same, it would be possible for someone to connect a high power device (like the immersion heater) and overload the inverter and batteries and causing damage or worse.

I want to change the inverter connected plugs and sockets to something different from the rest so that this cannot occur by accident.

The inverter is only 1500 watts so I imagine that 5amp plugs etc should be sufficient for the computer, 14 inch TV and lights etc. Any suggestions for the said plugs and sockets?

Thanks, Stu
 
How about some kiddies socket guards that you mark up with labels or a marker pen? That way there is a visual reminder. Or you could change all the high current items to blue 16amp plugs and sockets.
 
Perhaps IEC plugs and sockets?

or there are some mains plugs and sockets with a T shaped earth pin, we used to use those for clean supply in a computer room.
 
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You could try to find Walsall Gauge stuff, which is exactly the same as normal 13A but with the pins rotated through 90 degrees. It all seems a bit complicated, though. Why not just fit a suitable circuit breaker to the inverter's output?
 
Just don't let anyone attach the matching plug to an appliance which can draw more than 5 amps!

http://uk.rs-online.com/web/p/electrical-sockets/2676609/

They will also be a straight swap assuming they are to replace conventional, domestic 13 amp outlets.

Thanks for the link. I'd seen the round pin plugs but didn't find the wall sockets.

At some point we hope to trade up to a bigger boat and it struck me that a new and unsuspecting buyer could cause themselves ( or even just the batteries) some serious damage if they were to get it wrong. By changing the relevant plugs and sockets and maybe a warning notice on a bulkhead a possible problem could be averted.
 
I reckon the old round-pin plugs (as used before ring-mains and 13A) would be the very thing. Designed for the job, in fact. Since you probably have radials rather than a ring you don't need the plug-top fuses anyway. The system is actually still compliant with UK shoreside regs, because it gets used in posh living rooms to plug table lamps into the lighting circuit (so the maid doesn't plug in the hoover and overload it), and (in the 15A version) in theatres because they don't want fuses blowing way up in the roof where you can't reach them.

See http://www.tlc-direct.co.uk/Products/TLPT5.html / http://www.tlc-direct.co.uk/Products/GU3080.html

Pete
 
The idea of an auto changeover switch to shift the power outlets from shore power to inverter is a bit scary. If the 2 became connected together you could have a real problem fire or certainly fuse faulure. I would suggest you consider for safety removing that switch and just having a few well marked different sockets connected directly to the inverter.
So a person has to at least choose to plug into the inverter system. good luck olewill
 
The idea of an auto changeover switch to shift the power outlets from shore power to inverter is a bit scary. If the 2 became connected together you could have a real problem fire or certainly fuse faulure.

These switches are made for the purpose, and always break-before-make. I don't think there's anything to worry about.

Pete
 
We have a "Blue Sea" source selector switch covering the whole 240 ring main and the inverter input is protected by a 5amp mcb. The immersion heater is only wired to the shorepower input.
 
Our small inverter powers all the sockets but we have a double pole switch to select shore power or inverter to stop the deck shore power socket being live when inverter on and, to stop both being live at the same time. It would be easy, as mentioned before, to install a circuit breaker to stop overloads but never needed to as the inverter sounds an alarm and trips if overloaded when I've forgotten to switch the immersion heater or battery charger off.
 
Some of the mains sockets that I have on board will still work when there is no marina power connected, through the inverter. I have a change over device that senses when the mains is connected and this disconnects inverter power when the mains is reconnected or re established.

Problem is (potentially) that because all of the sockets and plugs on board are the same, it would be possible for someone to connect a high power device (like the immersion heater) and overload the inverter and batteries and causing damage or worse.

I want to change the inverter connected plugs and sockets to something different from the rest so that this cannot occur by accident.

The inverter is only 1500 watts so I imagine that 5amp plugs etc should be sufficient for the computer, 14 inch TV and lights etc. Any suggestions for the said plugs and sockets?

Thanks, Stu

If you think the idea will work for you why not do as you suggest. Fit old style 5 amp round pin plugs and sockets for those items..

It used to be possible to get fused 5 amp plugs but I dont know if they are still available, in fact pretty sure they are not. Therefore you will have to consider fusing the supplies to the sockets.
 
If you think the idea will work for you why not do as you suggest. Fit old style 5 amp round pin plugs and sockets for those items..

It used to be possible to get fused 5 amp plugs but I dont know if they are still available, in fact pretty sure they are not. Therefore you will have to consider fusing the supplies to the sockets.

The round pinned ones are available through stage lighting suppliers but are usually un-switched. As to 5amp square pinned plugs, what's wrong with buying a bag of 5 or even 3amp fuses and replacing the 13amp ones in the plug tops?
 
what's wrong with buying a bag of 5 or even 3amp fuses and replacing the 13amp ones in the plug tops?

I think the object of the exercise was to prevent higher power appliances being plugged into the circuit supported by the inverter. Hence the idea of using some type of plugs and socket, other than the normal 13 amp square pin type, for the low power appliances.
 
I think the object of the exercise was to prevent higher power appliances being plugged into the circuit supported by the inverter. Hence the idea of using some type of plugs and socket, other than the normal 13 amp square pin type, for the low power appliances.

Bang on VicS. It isn't a problem for us because we know the score. I had thought maybe some plastic signs with warnings on may suffice, but felt instead that a single prominent warning (with the clearly different plugs and sockets) would ensure that if the worst happened it would have to be suicide rather than murder, and they would have to swap plugs to do it. Sounds a bit far fetched I know, but ignorance knows no bounds.
 
Just going to say the same. Why not have a set of 3-pin 13A sockets that run off 240V shore power, and a few others that run off the inverter, both clearly labelled what the maximum wattage they will supply is. Then it is up to the user to make sure they follow the labels.

After all, what is the worst that can happen? If an appliance with too much power draw is plugged into our inverter (which I have occasionally done), it just cuts out. As far as I know, with my limited knowledge of such things, there is no damage to inverter or batteries. I don't know if they are all like this, but ours certainly keeps going after the offending appliance has been unplugged, and something more suitable is plugged in.

Rob.
 
I think the object of the exercise was to prevent higher power appliances being plugged into the circuit supported by the inverter. Hence the idea of using some type of plugs and socket, other than the normal 13 amp square pin type, for the low power appliances.
Then take my first suggestion. Put the inverter output through a 5 or 3 amp mcb.

You are getting a bit aggressive as you get older Vic old boy, if you don't mind me pointing it out!
 
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I think the object of the exercise was to prevent higher power appliances being plugged into the circuit supported by the inverter. Hence the idea of using some type of plugs and socket, other than the normal 13 amp square pin type, for the low power appliances.

Hmm. One solution is to fit a circuit breaker in the inverter-supplied circuit. The other is to change the plug on every single appliance to be supplied by the inverter and, if it's something which might also be supplied by shore power, carry suitable (13A -> 5A) adaptors or duplicate equipment. On of these solutions sounds just a tad simpler than the other to me.
 
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