Proposed power and charging arrangements for a narrowboat

[Bru]

All I gonna say is that in a quarter of a century of knocking around t'cut I've seen every possible method of providing sufficient voles (in-joke on the canals version of this forum) to juice up all the kit on a narrowboat

And without a shadow of a question of a doubt the most sucessful solution has definitely been to fit a second big alternator to the boat engine coupled to a meaty battery bank via a decent controller

There is some merit to the idea of fitting a 240v AC unit effectively turning the engine into a genset but personally I'm not that keen on the idea because it tends to lead to skimpy battery banks and small invertors and thus to people running their nbloody engines all the damn time in order to power the AC circuit

That's nearly as heinous a crime as running a generator on the back deck and that is plain anti-social - especially at well past closing time four feet from where somebody is trying to get to sleep on a GRP cruiser. They were offered the option of switching it off or drying it out

 

[oldfatgit]

All I gonna say is that in a quarter of a century of knocking around t'cut I've seen every possible method of providing sufficient voles (in-joke on the canals version of this forum) to juice up all the kit on a narrowboat

And without a shadow of a question of a doubt the most sucessful solution has definitely been to fit a second big alternator to the boat engine coupled to a meaty battery bank via a decent controller

There is some merit to the idea of fitting a 240v AC unit effectively turning the engine into a genset but personally I'm not that keen on the idea because it tends to lead to skimpy battery banks and small invertors and thus to people running their nbloody engines all the damn time in order to power the AC circuit

That's nearly as heinous a crime as running a generator on the back deck and that is plain anti-social - especially at well past closing time four feet from where somebody is trying to get to sleep on a GRP cruiser. They were offered the option of switching it off or drying it out

Thank you. Will do more research with the only problem being additional cost.

 

[Ex-SolentBoy]

A built in generator is not an alternative to a decent inverter. I have both. The advantage with the built in generator is that when the engine is running can strict huge amounts of AC and still move the battery charge in the right direction.

Also, the batteries will charge much quicker than from a normal alternator setup.

You can never have too much battery capacity. We have about 1000 amp hours.

 

[Gumpy]

Sometimes people on here post things that are dangerous.
The AC earth must be bonded to the hull on a steel boat you then use an isolating transformer or GI to seperate the shore line earth from the system thus preventing galvanic corosion
If the earth is not bonded to the hull if a live touches the hull then it will go live as there is not enough conductivity in freshwater to trip an RCD every time. This means that if you touch the hull you could be dead.
Secondly the DC negative should be bonded as close as possible to the AC earth.

If you wamt some sensible info look at the tech tips on www.smartgauge.co.uk


Julian

PS ive been wiring narrowboats for over 20 years and am also a qualified electrician.

 

[Stemar]

If you get one of these controllers for your solar panel, it will charge both batteries. You could set it up to ensure your engine battery is fully charged before shoving anything into the domestics abd you'll never have to worry about it again.

Add a VSR on the alternator that tops up the domestics before going for the starter would make sure you don't run the starter down trying to charge the domestics if they're a bit low and I reckon you're home & dry for the 12v system.

With the prices the same site charges for rigid panel, you could up your solar power for not a lot of money and reduce your need to run the engine if you don't want to move. (no connection, just a satisfied customer)

 

[oldfatgit]

Sometimes people on here post things that are dangerous.
The AC earth must be bonded to the hull on a steel boat you then use an isolating transformer or GI to seperate the shore line earth from the system thus preventing galvanic corosion
If the earth is not bonded to the hull if a live touches the hull then it will go live as there is not enough conductivity in freshwater to trip an RCD every time. This means that if you touch the hull you could be dead.
Secondly the DC negative should be bonded as close as possible to the AC earth.

If you wamt some sensible info look at the tech tips on www.smartgauge.co.uk


Julian

PS ive been wiring narrowboats for over 20 years and am also a qualified electrician.

Thank you very much. Please rest assured that I am not going to wire a thing until I am absolutely sure that I have got it right, furthermore, I am likely to employ the services of an experienced electrician to thoroughly check the safety of the system before the boat is put in the water. In my bench testing I have found that by connecting the bonding to the DC negative any noise produced by the inverter is reduced almost to zero on audio equipment so was going to check out the pros and cons of connecting the two in any case and notwithstanding the direction the thread was going. This because on my yacht the 2 are connected and with no apparent ill effects (including when connected as did happen with reverse polarity). However it is a GRP boat but the anodes are connected to the bonding. Given your emphatic advice I will ensure the 2 are properly connected and continue to monitor for reverse polarity. My idea regarding testing for an unwanted connection was only prompted by the previous post regarding the risks inherent with reverse polarity.

 

[Gumpy]

Please dont take offence My comment was not aimed at you but at the previous post you refered to

 

[oldfatgit]

Please dont take offence My comment was not aimed at you but at the previous post you refered to

Absolutely no offence taken by me and I hope not by anyone. Thank you again for your advice, much appreciated.

 

[sailinglegend420]

Please dont take offence My comment was not aimed at you but at the previous post you refered to

If people make mistakes here or don't give the complete picture in a posting then we all welcome feedback - not criticism.
This post has got a little confused as I was editing my posting that you commented on at the same time as oldfatgit was replying and copying my original unedited post.

I was making a valid point about the possible dangers of a non-marine charger being used on a boat. I should have left it at that and not over complicated my post without giving the full picture.

What I should have simply said was that if you are not a qualified MARINE electrician then don't touch or install any AC equipment.

I think the OP has at least now got that message.