sparrks
I guess that's possible it may blow the fuse, the alternator would be the higher voltage source, but the leisure battery will still be the lower resistance source. but why on earth would you fit only a 15-20A fuse? When a leisure battery is flat, say to recommended 50% max, connecting it to a charged starter battery with alternator running would blow the fuse anyway. All the advice I heard in the past recommends that you run the engine whilst using these large inverters, however, mine's only 150w so is not a concern.
Poppy, who's doing a self build and starting from scratch would be best advised to go for a decent split charge taking the full output current from the alternator as required by the battery. This would require a heavy duty relay and cables which would also keep the volt drop to a minimum, helping ensure the maximum charge rate possible.
My charger is rated at 50A, when I had one battery out of the two fail the other year it was kicking out up to 49A. I'm sure if I had stumped up the money for the 100A model it would have been higher.
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Poppy
Oh WOW me likes this one....do you know where it's from??
Poppy
Ummmm, I do believe I've just made my 1st expensive mistake!! Took delivery of a 2000w inverter, oh well, not much I can do about it now.
outtolunch
that one does not appear to be available anymore but I found this alternative at £50
View attachment 10937
also available with an expresso capability at £70 or deluxe version with pressure guage at £120
View attachment 10938
but I'm afraid I am now going to introduce the Atomic which is so beautiful you will not be able to resist it
View attachment 10939
but at £259 you might just say sod it I'll buy some posh instant
Bigpeetee
I've got a 2000w inverter for important things like hair dryers and microwave etc not the end of the world if you limit the use and have a system that can cope then all is well.
My comments re fusing the charge circuit at 15-20 amps relates to factory built vehicles predominantly, where the requirements for using battery power over extended periods is still not catered for. The majority of MH's still go to a site and rely on hookup for power and a gentle top up whilst driving. The battery is only for use during that stop in a layby for a cuppa so never gets used in anger.
Designing for extended use off grid is an altogether different thing, where even the smallest of voltage drop is significant, where everything needs to be designed to provide maximum efficiency where ever possible. However, for some of us, there are certain things that we can't do without AND don't come in power economical sizes ie hair dryers. Not my choice you understand but in the effort to keep the peace, some things have to be accepted.
SO, if you cannot find an alternative, design or modify your power set up to at least cater for these "creature comforts", easier if building from scratch, more complex if trying to upgrade an existing build.
Several "House rules" when using power hungry kit, when blowing hair, turn off if just fiddling. Get the inverter off as soon as finished using (I've forgotten on a couple of occasions and it does hammer the batts) Don't use a huge inverter to run small power items, remember, a 12v to say 19v charger for a laptop is just another inverter, just a small dedicated one, but try to run everything off 12v if poss and use LEDs for lighting.
With your 2000w inverter, make sure that the connections to your bank of batts is solid and thick (I've got about 300AH of batts to run inverter using meter tails for connecting cables and a solid connection to the chassis)
Example of where I'm up to now:
View attachment 10940
sparrks
Just a couple of things, looking at your drawing have you got a battery isolator switch? it's not shown.
It's a shame you can't get a bigger shunt for the inverter - it would be great, but a bit scary seeing it pull the full load.
Bigpeetee
Chose the shunt to monitor charging rates more than anything, even so, as the meter is self driven it miss reads when the inverter is in use showing a charge rather than discharge!! Circulating currents etc.
It also gets upset when the transmitter is on, again earth currents and electronics!! Still it lets me monitor the voltage state and current.
As for low voltage shunts, the best I used in work was a copper bussbar with a precision saw cut, use to measure 50volts at over 2000A The bussbar riser in the telephone exchange was by memory 16x 8"x1/2" alloy for each polarity. At the far end on max load you were allowed by memory 0.25 volt drop over 100metres
Makes MH power seem quite tame!!
sparrks
I was impressed with the battery rooms in the telephone exchanges that I've been in, those individual cells were massive. I've always been intrigued by the the 50V telephone system and associated volt drop.
Worked in a factory down in Portsmouth which made Chaff for the military. The machines which melted the glass were I think 2v at 1800A - could put your hands accross the busbar supplying them but wouldn't want to short circuit it.
Poppy
that one does not appear to be available anymore but I found this alternative at £50
View attachment 10937
also available with an expresso capability at £70 or deluxe version with pressure guage at £120
View attachment 10938
but I'm afraid I am now going to introduce the Atomic which is so beautiful you will not be able to resist it
View attachment 10939
but at £259 you might just say sod it I'll buy some posh instant
Ummmmm food or should I say coffee for thought
Poppy
Thanks for that & the diagram. Yes, I'm building it up from scratch & plan to hook-up, but ideally want to do mainly stealth whilst traveling alone.
ivecotrucker
Hi Poppy. You asked "...do sealed batts require venting ?."
There are 2 types of normal wet batteries: 1) 'sealed, no maintenance batteries' , those that are just "sealed" (but these actually do vent explosive gases under certain conditions) & 2) "sealed re-combinant" which, in theory, should not vent any gas but can do if under severe stress. How do you tell the difference between the 2 ? -actually very difficult & highly unlikely that the salesperson actually knows. There are also other expensive types such as AGM batts etc. which can also vent explosive gases under certain conditions.
Therefore the general rule is that battery compartments should always be ventilated.
Now I'm not being stroppy, Poppy, but looking at your other items 'wanted on the road' I do wonder if you are seeking the peace & solace of wild camping in truly wild places or are you trying to take your house/flat with you on wheels ?! To some people at least part of the allure is simply to get away from the C21st & all it's technological contranglements and to return, briefly, to the simple life. Perhaps other folk feel that they 'need' every modern gizmo at all times. No offence intended, just food for thought perhaps.
There are 2 types of normal wet batteries: 1) 'sealed, no maintenance batteries' , those that are just "sealed" (but these actually do vent explosive gases under certain conditions) & 2) "sealed re-combinant" which, in theory, should not vent any gas but can do if under severe stress. How do you tell the difference between the 2 ? -actually very difficult & highly unlikely that the salesperson actually knows. There are also other expensive types such as AGM batts etc. which can also vent explosive gases under certain conditions.
Therefore the general rule is that battery compartments should always be ventilated.
Now I'm not being stroppy, Poppy, but looking at your other items 'wanted on the road' I do wonder if you are seeking the peace & solace of wild camping in truly wild places or are you trying to take your house/flat with you on wheels ?! To some people at least part of the allure is simply to get away from the C21st & all it's technological contranglements and to return, briefly, to the simple life. Perhaps other folk feel that they 'need' every modern gizmo at all times. No offence intended, just food for thought perhaps.
Poppy
No it's an HP & the writing is Soooooo small lol output 18.5 2nd one is 19v
Poppy
LOL no I don't think you're being stroppy....On my own, I will be wild camping...only needing my laptop to upload the pic's of the day (bit of a photographer & can take around 200\300 pic's in one outing) However, when my partner is with me, on the odd weekend ere & there,,,she will require home comforts, so I need to cater for the pair of us for different needs as & when
)