# electrical ignoramus



## smifee (May 17, 2005)

i can't help it i am a cack handed technical thickie.

have never seen this suggested anywhere and suspect that to you techies it will be blindingly obvious why it won't work but here goes anyway.

i want to use 3 large leisure batteries and charge them from solar panels, the engine and a small generator. if i connect an inverter close to the battery using the right size cables can i run a lead from the inverter to the van's mains input socket.

this would mean i could use all the van's mains sockets and not just the inverter socket.

the only problem i can see is disabling the mains battery charger to prevent the batteries trying to use their power to charge themselves.

go on then tell me why it won't work.


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## DABurleigh (May 9, 2005)

smifee,

The inverter takes its energy FROM your 12V dc battery(ies), converting it to ac mains, but at a less than perfect efficiency, so some of your battery energy is lost in heat. If you then wish to use that mains to CHARGE your battery(ies), then you will inevitably be losing more charge than you are putting in.

That apart, the rest of your post is quite valid.

Sorry if I have got the wrong end of the stick.

Dave


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## smifee (May 17, 2005)

thanks dave ... so if i have the installed battery charger replaced with one that i can turn on and off it should work.

i might have to go for a lie down. usually when i have what i think is a good idea someone says "ah it won't work because ........"


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## 91929 (May 1, 2005)

*Electrical ingnoramus*

8O May also have got the wrong idea :?

8O You can NOT charge them from all the sources at the same time One or two of the devices will probably blow up ... :?

 However if you mean to use each item to individually charge the batteries as a 3 battery bank this is possible using a complex swithing system.
So That:- only one of the devices is ever connected to the battery bank at once AND no two charging devices can ever be connected together

8) :roll: If you have the knowledge to carry out charging with three seperate devices Then you could add more Solar Panel, Wind generater, Mains, Petrol Genny, Van engine when on the move

:? Dont know where the inverter comes in except for the power to drive it comming from the three batteries

Check the Technical Section of this Forum

:idea: I am sure that some items have been written about wiring up 2 batteries 7 associated switchin & charging :arrow:

:idea: Also look up some items in MMM where you can get some wiring diagrams

8) Good Luck & dont boil the batteries.  They dislike it!


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## DABurleigh (May 9, 2005)

smifee,

Well if you feel you have to replace a charger and buy an inverter, then depending on the size of inverter you are after, consider an integrated inverter-charger.

I have gone for one of these, which may well be way over the top in functionality and price for what you are after, but gives you a feel for the art of the possible in such an integrated black box, given you are thinking about all of generator, inverter & charger:
http://www.victronenergy.com/DatasheetsPDF/SinusInverterChargers/GBPhoenixMulti.pdf

Having said that, there is much to be admired in the KISS philosophy, so do the bare minimum and see how you get on!

The other think to think about is if you have an absorption 3-way fridge, you don't want it to run off mains when you are running the van's mains from the inverter. If the fridge uses a manually switched energy source, you can simply switch to gas. Some more recent fridges autoswitch the energy source, however, in which case either run a fused fridge power wire to the inside of the van's hook-up/ generator socket, or use a relay to ensure the fridge is never powered from the inverter output.

Regarding connecting multiple charging sources, this is entirely possible:
http://www.adverc.co.uk/technical/technical-boat.asp
though one needs to ensure each is regulated with diode protection, as, yes, "some don't like it up 'em", to use a technical term.

Dave


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## smifee (May 17, 2005)

thanks pete .... no need to swear wiring diagrams indeed.


the idea is to be independant of mains hookup. i'm a football addict and am going to italy for 6 months in sept and want enough power to run sat tv for hours & hours at the weekends.

when i get new van in 2 weeks i'm going to a company i saw at soton boat show. they do 'battery management' which apparently involves replacing battery charger, adding a gizmo to the alternator and fitting solar panels.

i have never seen any vans with a mains lead coming out of the van into the mains input and having had an inverter in a caravan i'd wondered if it was possible to get mains to all the sockets from it. as they are supposed to be experts on it i'll see what they say. 

not wanting them to identify me as a technical pleb too early in the business i thought i'd fly the idea here


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## smifee (May 17, 2005)

thanks again dave ..... adverc are the company i'm going to. waiting for a reply after they get back from new year hols.

saw the victron at boat show - big heavy blue thing about £1200. they couldn't help when, in my ignorance, i asked for a 2.5kw inverter.

i just need to get views of real people after scrambling my brain on the technical websites.


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## DABurleigh (May 9, 2005)

Victron do a 2kW (25deg C) inverter:
http://www.victronenergy.com/DatasheetsPDF/SinusInverters/GBPhoenixInv.pdf
and inverter/charger (as per my earlier link).

I can't see what you need 2.5kw for, though.

Mine is the Phoenix Multiplus compact 12/1600/70. Ben & Lizzie on MHF have the same, and Dave (nukeadmin) has the 12/1200/50.

Dave


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## AutoK (May 1, 2005)

Hi smifee
I think you are over complicating things here!
If you are thinking about running an inverter from your vehicle (starter) battery in order to charge your leisure battery(s), then I would not advise this as you would quickly run down the starter batt.

If you are suggesting running an inverter from your leisure battery(s) and then feeding the output back into the mains hookup, then why???
taking power out and then feeding it back in, is pointless.

If as you say you just need to power your various appliances when not connected to any mains, then your power must come from somewhere, simply connect your generator to mains hookup, I would't spend money on fancy gizmos, or expensive inverters, remember, inverters have to get there power from a battery, which will eventually run down.
Solar power will help keep batts charged, but I would use a good generater, maybe a Honda eu20 2kv.

Cheers.
Kieran.


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## DABurleigh (May 9, 2005)

Kieran,

I agree smifee needs to examine carefully his energy & power needs before buying anything expensive or complicated.

However, if he anticipates running TV for long periods each day, then a solar panel isn't going to replenish what he takes out.

He then needs to look at his generator & charger combination in the context of his anticipated site(s) to see whether running a genny for the time his charger needs to replenish his batteries is acceptable or not (to any neighbours rather than just himself). 

Similarly for idling his engine with the alternator charging the batteries. (Honda EU gennies are quieter than an idling motorhome diesel engine and are designed for longer idling without engine damage).

I'd be interested in the setup Adverc proposes for him.

Dave


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## smifee (May 17, 2005)

thanks to all of you for the info

clarification:-the idea is to get 240ish volt supply to the 240v sockets in the van without being connected to the mains.

the reason that i want to do it is that i have used an inverter before and found it inconvenient and dangerous to have cables all over the place. i thought this might be a better solution.

want to use the solar panels for day to day use e.g low wattage kettle & toaster for bleary eyed breakfast but will use the generator, honda eu10i, when consumption is heavy. intend to do 90% wild camping. 

it seems so simple but never seeing anyone else doing it i thought i just couldn't see the snags.

new van has one gel leisure battery under driver's seat which i want to remove. there is an underfloor locker that runs the full width of the van with room for any number of large batteries. thought i could put 3 high capacity batteries, battery charger and inverter in there and run a cable from the inverter out of the locker to connect to the mains in socket on the exterior of the van.

will let you all know how i get on with adverc.


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## AutoK (May 1, 2005)

Hi Dave, Hi smifee!!
You just want to get 240ish volts into the mains hookup when not on a site!
then as I see it you only have one choice, just use your Honda gen connected to mains inlet on your van, if you are wild camping 90% of the time you won't bother the neighbours, if you don't want to use the gen all the time, then by all means just run off your leisure batts for a short time.
By all means use an inverter to get 230v ac from your leisure batts, but sooner or later you will have to get re-charged, again from either your generator or a campsite with mains hook-up.
I am assuming of course that your van's charging system will re-charge your leisure batts when connected to mains hook-up.

Or maybe I think I have had a bit too much Christmas spirit, and have totally missunderstood you post.

Cheers.

Kieran.


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## Mat7 (May 15, 2005)

I may be just pointing out the obvious here, but if you are going to the trouble of installing batteries and chargers and solar panels and inverters, then surely it cant be much beef connecting up a dedicated socket inside the motorhome that is directly connected to your inverter? As long as you label it somehow and don't forget to put a on/off switch in for the inverter? i sure you could locate it near your TV and when on a camp site simply swap plugs between mains circuit socket and the inverted socket(??) circuit!

cheers for now
Matt 8O  8O


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## smifee (May 17, 2005)

i think perhaps i should have made clear that i am a serial electric consumer.

i couldn't join the bucket and chuckit brigade with their sackcloth t-shirts, hand knitted socks and rain hats made from leaves.

let me take you through the start of my day when i'm in the van. 
0600 woken by the goblin teasmaid giving me a ......no stop dreaming back to reality. i meant the need to answer a call of nature. whilst up i plug in the breadmaker that i loaded the night before.
0730 woken by the smell of bread cooking. put the electric kettle on, the telly on and plug one of the phones in to charge. fresh bread with breakfast but it must be toast with marmalade. plug toaster in and switch kettle on. after brekkie use the electric knife to cut the bread to make the sarnies for the days jolly.then out cycling or walking for the day leaving the solar panels to fully or partly charge the batteries.

i don't want to be scrabbling around putting & taking plugs in & out of the inverter nor do i want to be restricted to one socket.

hope that explains the WHY?


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## Mat7 (May 15, 2005)

ok i get the message!!!!   

my advice to you is buy the most expensive generator you can aford, probably one with electric start and ultra quiet, -- ie all the power you could ever want at the touch of a button!! (and could proably be linked to a timer so your bread maker comes on in the morning before you wake up!)
of course the main problem with generators is where to put them and noise!, but hey you can always turn your TV up louder! 

cheers for now 
Matt  8O


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## smifee (May 17, 2005)

thanks matt but that was my first thought but i've learnt not to put all my eggs in one basket cos i smash em when i get smashed and fall down giggling.

so i'm going for as many sources of power as i can. have been stuck in france when fuel supply problems so if there's 'free' electicity going i'll have some of that and back it up with a genny. any fuel supply problems and i just have to cut down on consumption but still got power.

didn't realise there were so many forums. didn't scroll down the page far enough. must go and do my st george bit. the dragons finished nights and will be awakening soon. not a pretty sight. hope she doesn't find this site and i know none of you will tell her when we meet.


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## smifee (May 17, 2005)

*update*

realised that i was going to have 4 companies involved in electrical installations and decided that they would point the finger at each other if i had any problems.

so went to the company who were going to fit the most gear and asked if they would do it all. van bitz said yes.

this is what they are going to do:-

remove leisure battery from under driver's seat and split charger relay.
install [email protected] elecsol batteries in a purpose built compartment in the garage. install nagares 180amp split charge relay.

install [email protected] watt solar panels

install mobitronic inverter 8200-012v next to battery bank with remote control next to hymer control panel.install mobitronic 945-012TC 45amp charger & temperature sensor.

rewire hymer ring main to incorporate UPS function of the inverter. isolate fridge/freezer from hymer ring main.

install wiring for 12v microwave direct to battery bank

install alpine IVA-D300R multi-media screen & NVE-N099P DVD navigation unit with TMC antenna & remote control

install mobitronic RV54 colour monitor, where rear view mirror was, mobitronic RV-600 switching box with selector switch on dash, connected to [email protected] RV27 cameras. one rear view. the other mounted on UK front offside to assist view from LHD drivers seat at roundabouts in UK.

install strikeback alarm

install rac trackstar

install oyster twin lnb sat tv system

i'm bound to have forgotten something :roll:


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## Mat7 (May 15, 2005)

Crumbs thats gonna be quite some set up! I'll bet they will want showcase that job when it is complete! 

8O  8O  8O

Cheers for now
Matt


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## 88790 (May 9, 2005)

It would be worth seeing if you can get a display of some sort indicating the state of charge of your batteries etc so that you know where you are!

I believe but please check, that the Victron units are predominantly for setups which use site mains input as well, here they use their own built in inverter to supplement the mains current available, which can be low on some sites.

Van Bitz also do a battery device to make sure that the engine battery is kept up to charge, this would be useful if you are not going use the MH for a time, alarms can run batteries down.

I don't know what control you have on the purchase of the various options but it is worth looking at www.waeco.co.uk where in their Factory Direct option they may have either the charger you want or a good alternative.

I think the generator you have is fine because it produces the mains output by an on board inverter, should you be tempted to change make sure a nother one does the same.

Have you investigated the possibility of the generator charging the batteries directly and not through the mains charger? I am sure that would be the best way to get the maximum charge rate from it. It would only need an extra socket fitted outside or underneath your MH to facilitate this. You could still use your generator to power the mains socket, not at the same time though.

John


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## smifee (May 17, 2005)

hi jabber

hymer control panel will still display battery state & charge or discharge

eddie has talked me into the waeco mobitronic gear because he has used them for some time and their after sales is good. eddie has spoken to them and gone with their advice about the installation.

the battery master is being fitted - i knew i'd forget something

re charging direct - i have done this before but found i had to undo the cell plugs cos they gassed off. that was bad enough with one battery but with 4 i think i'll stick to the mains charger.

hi matt - i'll be charging admission

jeffus - i know you haven't posted yet but will want to know why i changed - i went for the alpine system over the pioneer because the dvd is left in a seperate slot. less risk of scratching the disc. whilst i was at van bitz they had a phone call from someone who was in calais and pioneer system wouldn't work because disc damaged.


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## 93703 (May 1, 2005)

*What I did*

My inverter is supplied by 3 leisure batteries which are charged via the alternator whilst engine running , by a solar panel through a regulator and when on hook up by the built in charger. I ran a cable from the plug in facility on the inverter via a 13 amp plug and installed 4 sockets where my wife wanted them plus one in the garage area of my van using domestic mains cable properly protected in sleeving .My Inverter is 1500 watts pure sine wave all the inverter sockets as we call them are properly labeled and are thus totaly independant of the original sockets in the van All I have to do to power these inverter sockets is to switch on the inverter it doesnt matter much if I forget to turn the inverter off when not in use but it has a warning light to tell when it is on.Did you know that you can get an inverter with a remote control as (T,V.) so the inverter can be installed in out of the way places and can be switched remotely ?


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## smifee (May 17, 2005)

hi malc

sounds very similar to my proposed setup but i particularly wanted to use the sockets already installed in the van. there will be a remote switch ( i can't have anymore remote controls or i'll be picking up the wrong one or losing them ) to switch the inverter on and a relay to automatically switch inverter off when mains is connected.

the inverter will be 2000 watt modified sine wave. i have expressed a preference for pure sine but eddie has said if the tv doesn't work off the inverter he will take it out and put a pure sine in FOC. he must be very confident cos the pure sine is £850 extra :!:


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## 88790 (May 9, 2005)

I have a friend, who is knowledgeable about these things and he has fitted a Mobotronics charger and is well pleased with it. If you have not done so it is well worth visiting their site.

I can understand your point on charging from the generator, some do charge at too high a voltage and cause gassing. The Mobotronic is a stage charger and should therefore make sure you get the maximum charge into the batteries. My only concern about the stage chargers is that they start at a higher voltage 14.4 - 14.8 and I just wonder if the onboard Truma and other electronic circuits are designed to withstand this voltage - worth a check.

Sorry, I am not trying to alarm you, these are just my thoughts on consideration of fitting a stage charger, you may have already considered this.

Sounds like your set up should be the dog's doo-dahs!


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## smifee (May 17, 2005)

thanks john - i'd rather be prewarned than something go wrong and hear that dreaded phrase 'i could have told you that'  

so keep the info flowing. because i am technically challenged i need these pieces of advice so that i can ask the right questions.

one of the reasons i use van bitz is that they don't treat me like an idiot even though they know that technically i am one. i get a full answer to any questions. on a previous visit eddie has even changed a gas bottle for me cos i didn't know the thread was reversed


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## james (May 15, 2005)

Hi smifee,
I think that you slightly missunderstood the bit I told you about the mains relay disconecting the inverter. How you should have it is both the hookup going to the normally open contacts on the relay and the inverter going to the normally closed contacts on the relay. The output of both supplies go to the standard ring main via the fuse and trip box. With the relay off the inverter is connected to the ring mains and the hookup is disconnected, with the relay on, powered by the hookup supply, the hookup socket goes to the mains and the inverter output is disconnected, even if the inverter is on.
If you have only a relay switching the inverter off and on, the hookup pins will be live while the inverter is on and if a hookup cable is connected, it's pins will be live as well.
Perhaps I have missunderstood you? I do have senior moments often enough! that is according to my wife.
By the bye, with this inverter, is it necessary to have a twelve volt microwave? you could surely use a mains one and have much more choice and they are far cheaper.
James


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## smifee (May 17, 2005)

hi james

oh no i didn't slightly misunderstand. i don't understand at all. years ago there was a series on tv explaining electricity. i videoed it and watched it 6 times. i still don't understand it    

it used to bother me but one of the advantages of getting old is that i don't care about things that i found embarassing years ago.

i'm just going by what van bitz tell me. they say mains input will turn the inverter off and it uses a relay. however it was your info that prompted me to ask the question so thanks again.


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## 88790 (May 9, 2005)

Morning Smiffee,

I have just been looking at the charger specified for your set up and noticed it has three separate outputs. You would use one output for your bank of three batteries and you would still have two spare (since the three batteries are connected together they could not be charged individually) this means you have two spare outputs, one of these could be used for the engine battery, a better solution I would suggest than the Battery Master and would also save money!

Just a thought.

John.


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## DABurleigh (May 9, 2005)

I have a similar issue in that though I have mains charger and alternator each servicing both vehicle and leisure batteries, and the solar panel the leisure one, too, I don't have the vehicle battery being charged when not connected to mains or engine running.

It is only an issue during a layup when mains will not be connected - which will be rare. If the vehicle battery ever loses significant charge, I'm tempted to use a wire to connect the vehicle and leisure positives with some resistance and a "pullable" fuse close to the driver's position, to be pulled before starting, rather than £70 for the Vanbitz offering merely to cope with a rare scenario.

Dave


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## 93703 (May 1, 2005)

*Earthing Inverter sockets*

A vital point I overlooked in my previous reply was EARTHING the Inverter sockets Some fitters of Inverters earth via the vehicle chassis which is no go You need to run a cable from the Inverter earth conection to a BRASS rod pushed into the ground and connected via a crocodile clip >Dont forget to take it in when you drive off.


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## DABurleigh (May 9, 2005)

The installation instructions for my 1.6kW Victron integrated inverter/charger state:

"In case of a mobile installation (connection to input AC with a shore power cord), the ground connection is lost when the shore power cord is unplugged. In this case the chassis of the product or the on - board section of the input ground wire must be connected to the frame (of the vehicle) or the ground plate or hull (of a boat)."

Dave


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## smifee (May 17, 2005)

evening jabber

cos i don't understand how these things work and interact with each other i tend to have belt braces and a piece of string.

so i am going to have the battery master - only necessary if veh not in use for some time - not planning to break a leg and have a few weeks in eytie hospital but who knows? 

have found entry in the estimate - "connect 2nd charger output to chassis battery for back up and maintenance charging"

evening daburleigh - hi dave

not having battery master won't save any dosh. it's one of several freebies. i know i pay for it somehow but saying no wouldn't save me anything. 

evening james

am having a 12v microwave so i don't have to start adding up the watts - tv, sat receivers, toaster, kettle & microwave. 

i think i'll need a 2 day familiarisation course just to remember what switch does what :roll:


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## 88790 (May 9, 2005)

Smiffee, quite underestand that, gives an added layer of confidence!

John 8)


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## 88724 (May 9, 2005)

Hi all

Dont know how I missed this thread, Somehow the maths just doesnt add up, because one 10 min session with the microwave per day is going to eat more amps than the solar panels put back, those 2 panels would be doing well to give 500 watts back total per day In Australia

3 X 125 ah Batteries

2 X 75 w Solar panels

And nowhere do I see the main question that needs asking? 

Smiffee 

TV wattage and How many hours each day

Bread maker same question

Microwave wattage how often 

Anything else ie Sat or whatever?

How often will you use hook up sites

How often and far will you be driving between sites (wild) If it is regular movement as a Smart reg been considered?

How long do you intend to stay on one spot wild camping

Were the Sun hours charts for Italy checked? what about after the italy trip when and were is the van going to be used, as this been considered?

How many genny hours are required to top up, if as I guess its a few every couple of days then its made the solar system pointless, a well thought out system would only require genny top up after a poor weather period.

Now if the people quoting did not bore you rigid with these questions and a fair few more, then the whole system is guesswork.

George


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## Road_Runner_644 (May 9, 2005)

Hi - Our van is setup to be able to wild camp for a few days without depleting the 12v side.
I have a setup that has 2 x 110ah batteries, a 100w solar panel, and a 2000w invertor. I also carry a honda 10i (800w) generator in case of total power drain.
In the summer in France, I find that during the day when we are on our trips, the solar panel provides enough power to keep the fridge running on 240v through the invertor, and enough to charge phones, keep gameboys charged, and the odd bit of tv/dvd.
What we lacked was a bulk charge backup when things went pear shaped. and a previous thread pointed to the answer, i hope.
The advanced regulator (Sterling from Georges links) bumf says it can pump up to 90ah back in to your batteries, this is way far above anything offered by genny's, fuel cells, solar panels or wind power. 
Tell me i'm wrong, but i wouldn't have the slightest problem running the van for an hour or so, even if the situation meant going for a quick trip to avoid offending neighboring campers, to put that much power back in to the system.

Cheers

Dave


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## DABurleigh (May 9, 2005)

Dave,

I understand that charging lead-acids at a rate of greater than 1/5 capacity (42 amps in your case) is not good for their life. I believe the Sterling unit can be set to a given maximum. 

Also, the charging current doesn't run at maximum until the batteries are fully charged, but tapers, so the average charging current is considerably less than the maximum.

Having the vehicle diesel engine ticking over for an hour would not be damaging, but I suspect would if it got to be a matter of routine.

You are right about in-built generator charging currents being relatively low. However, feed this output through a decent mains charger, and the charging current tends to be limited by the charger spec, not the generator output. Even a quiet Honda EU10i genny has the ability to charge at approaching 50A, through a decent mains charger.

All the above are factors in deciding on the bulk charging fall-back route that is best in your particular case (energy budget, frequency of moving on & site occupancy/ density). For the moment, I have limited the alternator charging side to thick welding cable and high current split- charge relays from the heavy-duty-as-standard alternator, with the money I've "saved" on anything more exotic being put towards a decent mains charger (actually an integrated inverter-charger-UPS) and EU10i genny to take with us on the occasions we think it handy and socially acceptable to use. 

Dave


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## 88724 (May 9, 2005)

Hi Dave (DA)

Rapid and full recharge, the Sterling unit will provide, A quick and balanced charge, the electronics control the maximum charge rate depending on the infomation it gets from the battery wiring ie its constantly re assessing the charge.

Many Battery manufacturers say that ampage can be higher than 1/5 or 20% for recharging, but 20% is a good rate of recharge anyway. Usually the only downside is the extra topping up required.

Using a decent mains charger can give a near perfect 100% charge, so you charge up on site then drive off to you wild camping spot, unfortunately while using a "split charge" system on the way you will actually be losing charge.

Here are the results for a test I did last year

"Right the results are in :

from fully charged at 12.93v (measured 12 hours after coming off the Sterling charger) connected bulb, it took 6 hours and 17 mins to reach 12.2v (ie flicking over backwards and forwards from 12.3v)

It was then fully recharged on the Sterling, allowed 13 hours to settle the voltage, reading was 12.94v flash 12.93v, the engine on the iveco was started, then I connected the battery using a good solid cable as before and drove this morning for 1 hour 14 mins, as soon as I got back it was connected to the same bulb (55w halogen) connected at 12 : 12 today, it started flashing between 12.3 and 12.2 at 5 : 37 PM today   

Same battery, same full charge by Sterling, only difference 1 hour 14 mins of extra "charging" as knocked off 52 mins off usable power !!"

You want to see the whole 15 pages its here at the SBMCC site

http://s3.invisionfree.com/SBMCC/index.php?showtopic=6571&st=180

BTW note nearly 10 months later the people with degrees who disagree and went away to prove me wrong have still not returned any opposing results.

Brief version

Alternator (standard) cannot fully charge a battery in fact you would be lucky to get 70% charge even if you drove for hours.

Two batteries when placed in parralel will level out charge wise, ie if you connect a battery at 50% capacity and one thats fully charged togethor they will level out at below 75%

So if you fully charge at a site then drove with a split charge connected you lose charge, if you drive round for long enough leisures and starter will eventually be around 70% ish or less again.

George


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## DABurleigh (May 9, 2005)

George,

I must confess after a while of being attracted to squeezing every last bit of charge into my batteries, I am now coming around to the views of people such as webwobin:

"Lastly vehicle charging systems tend to limit charging voltage to 14V for a 6 cell battery. This is done for several good reasons, maximise battery life and minimise topping up for a start (also not a good idea to let voltage rise above "critical gassing voltage" while the battery is still connected to equipment it is intended to run). So, rather than incorporate a special non standard charging system to totally charge your battery - with all the associated other features it makes more sense to have a 20% bigger battery and stick to standard and industry accepted charging methods."

Similarly my Victron mains charger has a "battery safe" mode. My leisure batteries require the removal of 4 seat bolts to check electrolyte levels; not onerous but off-putting enough. So I stick with 80% into nominal 220Ah, but then I have a very accurate 12V "fuel gauge":
http://www.victronenergy.com/DatasheetsPDF/BatteryMonitor/GBBMV501BattMonitor.pdf

and the ability to bulk charge at a reasonable rate to fill the tank when necessary. Indeed, that gauge enables me to regard electrical energy just as chemical energy in diesel or Autogas (sonic level gauge) or fresh and waste water levels.

Now, all that being said, I don't think as a result I will then "lose charge" through a split charge relay, because the charging terminal voltages by various means will be similar.

Regards,

Dave


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## 88724 (May 9, 2005)

Hi Dave

Couple of points

All charging causes gassing, charging is a chemical reaction, even if you use the weakest chargers possible ZIG split etc and remove the vent caps you will see gassing. Higher rate charging causes heat which evapourates some electrolyte off.

The fact that the terminal voltage stays over 13v at all times while on "split charging" does nothing top stop the leaching. Ampage is drawn not pushed, other than putting a diode between the Starter and leisure batteries you wont stop the starter battery leaching some charge from a fully charged leisure.


The first experiment to prove, used a 14v charger one full battery and one drained battery, even with a constant 14v the Charged battery lost charge and the low one gained. 


George


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## smifee (May 17, 2005)

hi george

nearly all of your questions were asked but i found that i was answering 'it all depends. sometimes i do sometimes i don't' :? 

unless i live my life as an automaton and do the same things for the same length of time every day i won't need the same amount of power every day. i would probably only use some appliances every 3 days - microwave & bread maker for example. 

i started off with the idea of working out the maximum amount i would use and then tried to find a system that could deliver it. i have now come to the view that it is better to plan for an average situation & not the worst case scenario :idea: 

as a result of the questions asked by van bitz i have changed my preference from 'smaller battery capacity with high charging' to 'higher battery capacity with lower charging'

why? because i found, in portugal for 3 months without hookup, when i used high charge i had to remove cell caps & top up :evil: 

with the proposed system i think the solar panels will be enough on light use days when i'm off walking or cycling all day. the generator will be used on weekends when i spend a lot of time in the van.

it was the van bitz questions on appliance use that made me realise i was never going to use the whole lot at once. apologies & thanks to all those of you who told me as much and could you please limit 'i told you so'
to 3 times each when we meet :wink:  :lol: 

i can still add higher charging capacity by installing a different altenator and/or adverc charge controller if after a period of 'suck it & see' i find that i do need a higher charge regime.

only time will tell. thank you all for your help, advice and opinions.


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## 88724 (May 9, 2005)

Hi Smiffee

Higher top ups in Portugal, depending were in the world a battery is intended to operate the electrolyte acid mix is different.

Battery intened for use in outback Australia would not work as well or last as long if Used in Alaska and Vice versa.


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## carol (May 9, 2005)

Hi Guys (it seems mainly guys)

I do not profess to know much about this lot and have been reading it through today - and one question no one has asked, and here I must admit to not knowing Smifee what motorhome you now have that this was all going on - but it sounds like a lot of weight - and therefore I hope you have a large payload not just for your batteries and chargers etc., but for all those appliances you want.

I had a very simple idea, well I thought so, about 2 years ago, and we could find no one prepared to fit it.

All I wanted to do, was to connect an inverter in such a way that when you were wild camping you could use all your elec sockets, but from Chelston to Mullacott Caravans here they first said yes, and then all said NO can't be done. Too dangerous.

So I have an inverter which I plug into a 12v socket they have fitted close to my batteries and charge/run everything from there....nowhere near as convenient as I wanted, but it works.

Carol


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## DABurleigh (May 9, 2005)

Carol,

Yes it can be done, and safely, too. I know Dave (nuke), Ben & Lizzie and me have this functionality. Basically you use any or every mains socket in the van when you like, and merely keep an eye on the electrical "fuel gauge" from time to time if you are not connected to external mains, whether from a site supply or genny.

You need to install it with some thought and expertise. Here are the instructions for this for all of the above installations:
http://www.victronenergy.com/upload/documents/Manual-ML-PhoenixMultiCompact.pdf

Dave


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## 88724 (May 9, 2005)

Hi Dave, all

Dave first off yes it can be done but not with every invertor, some are OK and some are not.

Problem is that electricians have to work to 16th Edition Wiring regs and for mobile installations, its not that clear what is OK and whats not.

Consider London Underground use Sterling Invertors, they have fitted each through an RCD!! because the Invertor is not earth bonded the RCD cannot trip its a waste of time and money, the only kind of shock you can get is live to neutral one which the RCD will ignore as the person being shocked just appears to be a resistive appliance.

Many installations I have checked would not pass a 16th edition inspection, some caravans and motorhomes have a 240v socket in the shower room !

I have discussed mobile installations with several pucker electricians and even they get confused, especially when there is more than one power source, because each as different requirements.

Many err on the side of caution with invertors and insist that they are used via the invertors own Socket.

Not one time served electrician spotted the following, I want you to close your eyes and imagine the little Blue plug on the side of your van, think about those three little Brass pins that you can grab hold of and occassionally you add grease too !

This is why I look at stuff over and over, its not just non camping electricians either, I have discussed this subject over and over on Camping forums and not one person, electrician or otherwise as spotted the danger.

*Carol whatever you do not not run your invertor through the normal sockets, if you still want to do it you need an auto change over switch and someone who knows what they are doing*


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## 93795 (May 1, 2005)

Hi George, I agree that the input plug on the outside would be dangerous if it was live, but if you are not connected to site mains wouldn't the main circuit breaker in the van be off, isolating the blue plug from whatever was going on in the van? I'm probably missing something here but this puzzled me when I read your post.
Phil.


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## 88724 (May 9, 2005)

Hi Phil 

No because if you are going to have the van's appliances running from the Invertor it needs to go through the distro board (for safety must go through the fuses) and this would not work if you switched OFF the main breaker.

George 

PS Imagine kids playing at campsite blue plug live. If I had used the system as proposed by a Qualified electrician this would have been on my bus !


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## 93795 (May 1, 2005)

Hi George. yes frightening isn't it? I didn't realise that you would have the inverter supplies going through the same control box. I assumed it would have its own so that either site mains through the original box or inverter mains through its own control box could be selected by the user.
Phil.


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## 90168 (May 1, 2005)

Well, being a simple kind of a guy, I solved switching between two inputs ( inverter or mains) the easy (cheap!!!) way ,
details are on my site about halfway down this page, http://www.bennythebus.co.uk/jan_2004.htm

this would also allow for generator input and also would not interfere with solar top-up either.
Cheers

Charlie


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## 88724 (May 9, 2005)

Hi Charlie

Were does the three pin plug lead to? (the one shown by the battery box)

Would that be live when on hook up? trying to picture where the wires lead to and how it would work.

If the power from Hook up and genny is fed to the twin socket shown on battery box then one of those sockets could have been used with No MCB or fuse protection.

Or maybe I am not seeing it right at all 

George


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## 90168 (May 1, 2005)

George, If you scroll down a couple more photos it shows you where the plug goes,(to a mini ring main) as the text says the twin socket comes from the rcb's via the hook-up, the plug is not live at all until it is either plugged into the double socket (hook-up or genny) , or plugged into the inverter socket,
the power from hook-up or genny is fed to that double socket but they are all protected as the socket is fed from the rcb, this also means you cant accidently use the inverter to power the battery charger as this is fed from anothe rcb

clear enough now???


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## smifee (May 17, 2005)

hi carol

it's all going in/on a hymer c614gt on a fiat maxi chassis 3900kgs.

i am very conscious of the weight. probably more so than most MHers in that i have weighed my van before adding the goodies. just as well as it weighs 54kgs more than hymer said it would :evil: 

re all sockets live:- the mobitronic inverter that i'm having fitted has a built in 'priority circuit' which to quote the blurb "As soon as an external power source is applied the inverter generates 230 volts from the mains not the battery". this means that i only have to switch the inverter off if the batteries are low and i'm not able to drive or run the generator. 

the seperate charger and inverter works out a lot cheaper than the combined victron that i was intending to have but the victron had a higher spec.


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## 88724 (May 9, 2005)

Hi Charlie

Thanks for the quick response, Amazing how clear it is after reading the next part on your site, nice little set up, any updates on the new one?

George


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## smifee (May 17, 2005)

update - have been using the system for a month now and it is FANTASTIC.  :lol:  

vanbitz say they have done a couple more since they did mine and a mate has just bought the inverter & charger from vanbitz to do his own installation. 

haven't got anywhere near low battery power even after a heavy football watching wet weekend. weather depression accompanied by football depression - i'm a saints armchair supporter.

didn't buy a microwave oven for the van and am having second thoughts about getting one now. only suitable location is the redundant high level tv cupboard. doesn't seem a good spot for something that heavy. where do i stow the glass turntable? is it overkill just so i can cook perfect scrambled egg? the 3 burner hob & gas oven have been adequate so far and being able to use a mains toaster at the flick of a switch is great.

will take some pictures & post 'em when the van stops still long enough to empty the boot/garage. that will probably be at the next weight check.


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## 88790 (May 9, 2005)

That all sounds great, I am really pleased for you!

Don't worry about the Saints, I am sure Harry and Son will get them sorted they already look a different team to me.

All the best,

John


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## james (May 15, 2005)

Sounds a good setup Smifee, Curry's do a dinky little 700 watt digital display/control microwave that only costs £29 so if it does not work out then it is no great loss. It is not as heavy as you might think and I Installed one in a top locker with no trouble. I tend to keep the glass plate in it as it is fairly well located, you could always wrap some bubble wrap around if if you were not sure. As always, once you have got one you wonder how you managed without.
James


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