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The plan is to run everything off 12V, except the fridge.  Charging will be from an LPG generator, but I will set it up to be used on shore power as well.  I plan to add a pair of 240V sockets at either end of the boat [and hope never to use them, but reality means....].  I aspire to add solar one day.

 

I had a look at this pretty picture from Victron:  

https://www.victronenergy.com/upload/documents/MultiPlus-system-example-5KW-24V-230V-AC.pdf

 

Skipping the series connection bit, can I check that this interpretation is correct?  All the positive leads from the batteries will be the same cable length.  

 

 

 

And a few more questions:

- can the same set up [socket?] be used for incoming AC, whether it is the generator or shore line? 

- apparently a galvanic isolator is needed on the earth side of the incoming AC [when on shore line, but might as well put it in]

- what size fuse in the picture above?

 

Grateful, as always,

 

greg

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Edited by Wittenham
it is not a nice enough picture to show twice
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If you put "sockets" which are really plugs, the pins are exposed, on both ends of the boat, the unconnected one will be live and dangerous when the other is used.

You need to have a double pole 2 way 20A switch to connect only one at a time to your internal wiring, rcd etc. The 2 earths can be connected permanently together before the galvanic isolator. and unswitched. 

 

Batteries should all have the same length cables both positive and negative otherwise they will not charge or discharge equally.

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1 hour ago, Wittenham said:

All the positive leads from the batteries will be the same cable length.

 

1 hour ago, Murflynn said:

negative leads should also be the same length

 

44 minutes ago, Boater Sam said:

Batteries should all have the same length cables both positive and negative 

See here...

http://www.smartgauge.co.uk/batt_con.html

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1 hour ago, Wittenham said:

The plan is to run everything off 12V, except the fridge.  Charging will be from an LPG generator, but I will set it up to be used on shore power as well.  I plan to add a pair of 240V sockets at either end of the boat [and hope never to use them, but reality means....].  I aspire to add solar one day.

 

I had a look at this pretty picture from Victron:  

https://www.victronenergy.com/upload/documents/MultiPlus-system-example-5KW-24V-230V-AC.pdf

 

Skipping the series connection bit, can I check that this interpretation is correct?  All the positive leads from the batteries will be the same cable length.  

 

 

 

And a few more questions:

- can the same set up [socket?] be used for incoming AC, whether it is the generator or shore line? 

- apparently a galvanic isolator is needed on the earth side of the incoming AC [when on shore line, but might as well put it in]

- what size fuse in the picture above?

 

Grateful, as always,

 

greg

image.png

I’m not quite sure what you mean by “a pair of 240v sockets”. Do you mean shore power connectors? If so, as said you will need changeover switchgear to select which socket is in use and isolate the other one. You cannot plug shore power into one end that leaves the connector at the other end live - BSS fail.

 

Do not be tempted to use a domestic 13A socket to connect shore power - that would be very dangerous.

 

Yes you can use the same shore inlet for both shore power and genny. 

 

Yes you can add a Gi (not mandatory, but a good idea. If you will have 2 shore inlet sockets, put the GI in the earth line between the switchgear and the Combi.

 

In order for the RCD to work when on genny you need to make sure the live and neutral aren’t “floating”. If they are, you need to bond the N and E wires together at the genny, best to do this using a special genny lead. Some genny’s are floating (need the NE bond), some are centre tapped or in some other way have the L and N related to earth. You need to know what type before you do anything, as bonding NE on a centre tapped genny will blow something up.

 

Fuse size - refers to Victron installation manual but I would imagine 250 to 300A, provided the cabling can take that much current safely.

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thanks all, very useful, and the smartgauge link answers the question.  To clarify on the 'sockets' at either end of the boat... sorry, foreign words, I meant power points [such as one would plug a hair dryer into].  There will be only one socket into which the generator/shore power is plugged.

 

image.png.78df9faf6844bd7360b1c46f0420d083.png

 

The generator is a Honda suitcase EU22i [suitcase].  Does that give enough info to answer the 'floating' question?

 

thanks

 

greg

 

 

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hair drier ................. no

electric kettle,.................... no,

coffee thing .... no

washing machine .. no

dryer ........... no

lpg generator no.

solar yes ...................

I think you have to accept, it's a boat, it's not a flat!

PS batteries can explode,  they are dangerous in the wrong hands!

good idea to have a plan, bad idea to do an install, imho.

I have met a number of people with no eyebrows, and they were the lucky ones. The other ones are still in intensive care, six feet under.

 

Edited by LadyG
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12 minutes ago, LadyG said:

hair drier ................. no

electric kettle,.................... no,

coffee thing .... no

washing machine .. no

dryer ........... no

lpg generator no.

solar yes ...................

I think you have to accept, it's a boat, it's not a flat!

 

I have a boat and not a flat but, unless I wish to sail without my trusty First Lieutenant (aka the Long Haired Admiral), which to be crystal clear I do not, there will always be a hairdryer! ;)

 

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11 minutes ago, Sea Dog said:

I have a boat and not a flat but, unless I wish to sail without my trusty First Lieutenant (aka the Long Haired Admiral), which to be crystal clear I do not, there will always be a hairdryer! ;)

 

Too tight to pay for a shampoo and set on a Friday?

I have not used "curlers/carmen rollers/crimpers" for about forty years. Short hair is the ideal, everything else is vanity.

Edited by LadyG
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27 minutes ago, Alan de Enfield said:

You occasionally need grab-handles to stop them slithering away.

 

I don't think so!

grrrrrrrrrr ................................... MEN !

Edited by LadyG
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On 26/03/2019 at 11:50, Wittenham said:

The plan is to run everything off 12V, except the fridge.  Charging will be from an LPG generator, but I will set it up to be used on shore power as well.  I plan to add a pair of 240V sockets at either end of the boat [and hope never to use them, but reality means....].  I aspire to add solar one day.

 

I had a look at this pretty picture from Victron:  

https://www.victronenergy.com/upload/documents/MultiPlus-system-example-5KW-24V-230V-AC.pdf

 

Skipping the series connection bit, can I check that this interpretation is correct?  All the positive leads from the batteries will be the same cable length.  

 

 

 

And a few more questions:

- can the same set up [socket?] be used for incoming AC, whether it is the generator or shore line? 

- apparently a galvanic isolator is needed on the earth side of the incoming AC [when on shore line, but might as well put it in]

- what size fuse in the picture above?

 

Grateful, as always,

 

greg

image.png

350amp mega fuse,, you may even need 450amp with an inverter that size. 

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4 hours ago, F DRAYKE said:

350amp mega fuse,, you may even need 450amp with an inverter that size. 

And short stonking fat cables too! Are you planning arc welding  off your batteries?    

 Its not a power station, what on earth are you thinking of? How big is your generator?

It will need to be huge to replace that power and fully charge the batteries.  in a reasonable time !

 

Batteries must be wired so that the sum of the length of positive and negative cables to each individual battery  is the same to each and every battery. In other words the resistance of the cables to each battery has to be the same to every battery.

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5 hours ago, Boater Sam said:

And short stonking fat cables too! Are you planning arc welding  off your batteries?    

 

oh, that's a good idea... a couple hinges on the water side door have rusted away and i was thinking about how to repair them ?

 

5 hours ago, Boater Sam said:

   

 Its not a power station, what on earth are you thinking of? How big is your generator?

 

Honda suitcase generator, 2.2kw

 

5 hours ago, Boater Sam said:

Batteries must be wired so that the sum of the length of positive and negative cables to each individual battery  is the same to each and every battery. In other words the resistance of the cables to each battery has to be the same to every battery.

yep, thanks.  I find I am slowly cornering the copper cable market.  Another helpful poster pointed me to this:  http://www.smartgauge.co.uk/batt_con.html  I am assuming 50mm^2 cable work?  [times the length of a piece of a string]

 

 

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26 minutes ago, Wittenham said:

I find I am slowly cornering the copper cable market.  Another helpful poster pointed me to this:  http://www.smartgauge.co.uk/batt_con.html  I am assuming 50mm^2 cable work?  [times the length of a piece of a string]

If you mean to use this to wire in the inverter you are way, way off.

 

Your inverter will be drawing 300 amps at 'full chat'.

50mm2 is rated at a maximum of 204 amps runs as a single core in 'free air'.

 

You will need at least 95mm2 giving 321 amps

or preferably (to have a bit of safety margin) 120mm2 giving 374 amps

 

If you are running the cables together (as in a 'group') then you need to de-rate them by a factor of 0.8

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On 26/03/2019 at 15:12, LadyG said:

Too tight to pay for a shampoo and set on a Friday?

I have not used "curlers/carmen rollers/crimpers" for about forty years. Short hair is the ideal, everything else is vanity.

As a long time liveaboard I sort of agree. We do have a good travel power and inverter set up and a tumble dryer ( never used so binning this week )  and we do not live like cavemen. However my missus never uses her hair dryer even tho the boat has the capability to use it and indeed we are on mains at present. Thing is living aboard and hobby boating are so far removed from each other that lifestyles choices differ between hobbyists and dwellers

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7 minutes ago, Alan de Enfield said:

Your inverter will be drawing 300 amps at 'full chat'.

50mm2 is rated at a maximum of 204 amps runs as a single core in 'free air'.

 

hmm... so that chat with the supplier turned out not to be so useful.  Thanks [in the long term, in the short term, however...]

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40 minutes ago, mrsmelly said:

As a long time liveaboard I sort of agree. We do have a good travel power and inverter set up and a tumble dryer ( never used so binning this week )  and we do not live like cavemen. However my missus never uses her hair dryer even tho the boat has the capability to use it and indeed we are on mains at present. Thing is living aboard and hobby boating are so far removed from each other that lifestyles choices differ between hobbyists and dwellers

I'm not sure what a travelpower is, I've seen them mentioned as the answer to battery charging via the engine power , so I "imagine" it's just a brand name for a big alternator in place of, or as an adjunct to, the standard alternator. If it is heavily demanding of the engine, that would mean less "glazing of bores", as the engine would be "working". 

https://fourcountiesmarineservices.com/alternator-upgrades/

PS don't bin your tumble dryer ........ recycle it it, keep the planet free of landfill :)

PS I'v found an explanation by four counties [Ed perhaps?], so I just need a single sentence summary. Thanks in anticipation.

 

Edited by LadyG
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16 minutes ago, LadyG said:

I'm not sure what a travelpower is, I've seen them mentioned as the answer to battery charging via the engine power , so I "imagine" it's just a brand name for a big alternator in place of, or as an adjunct to, the standard alternator.

Not quite.  Think of it as a 240V alternator and you will have the idea.  

 

They are added as an extra alternator and directly generate 240V when the engine is running instead of going 12V -> batteries -> inverter -> 240V.

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18 minutes ago, LadyG said:

I'm not sure what a travelpower is, I've seen them mentioned as the answer to battery charging via the engine power , so I "imagine" it's just a brand name for a big alternator in place of, or as an adjunct to, the standard alternator. If it is heavily demanding of the engine, that would mean less "glazing of bores", as the engine would be "working". 

https://fourcountiesmarineservices.com/alternator-upgrades/

PS don't bin your tumble dryer ........ recycle it it, keep the planet free of landfill :)

PS I'v found an explanation by four counties [Ed perhaps?], so I just need a single sentence summary. Thanks in anticipation.

 

Yes sort of :D Travel power is indeed a big alternater thingy. The great thing is via a magic box of tricks it delivers 3.5 k wattsits pure sine mains power. In effect we have three alternaters ont engine. They are awesome and I will not now have a boat without one either fitted or with an engine capable of fitting one to then Ed shiers could fit me one its something he does.

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Yes it is a high voltage alternator (thus delivers much more power for its physical size, compared to a 12v one) and the output is then fed into a black box, the output from which is 230v sine wave mains power, at 50Hz regardless of engine rpm.

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On 26/03/2019 at 14:23, Wittenham said:

thanks all, very useful, and the smartgauge link answers the question.  To clarify on the 'sockets' at either end of the boat... sorry, foreign words, I meant power points [such as one would plug a hair dryer into].  There will be only one socket into which the generator/shore power is plugged.

 

image.png.78df9faf6844bd7360b1c46f0420d083.png

 

The generator is a Honda suitcase EU22i [suitcase].  Does that give enough info to answer the 'floating' question?

 

thanks

 

greg

 

 

The shore supply connector fitted to the boat is generically refered to as an “appliance inlet”; the boat end of the shore supply cable will be fitted with a “trailing socket”. The shore side is a plug on the shore supply cable, and a socket on the supply bollard. We’re all used to taking the plug to the (fixed) socket, in this case we take the socket to the (fixed) plug; and then find new names for everything!

 

Edited by Eeyore
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22 minutes ago, Eeyore said:

The shore supply connector fitted to the boat is generically refered to as an “appliance inlet”; the boat end of the shore supply cable will be fitted with a “trailing socket”. The shore side is a plug on the shore supply cable, and a socket on the supply bollard. We’re all used to taking the plug to the (fixed) socket, in this case we take the socket to the (fixed) plug; and then find new names for everything!

 

Only by people who know what they are talking about, a majority of boaters plug the shore line into the socket on the back of the boat and the other end into the post. Just listen to them, I bet half dont realise its a plug on the boat or why.

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