Inverter for a motorhome to charge my bike

Katymac

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Mar 18, 2017
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When I was buying my bike the guy said I might need an inverter to charge my bike when we were not on mains

I didn't really understand it then & I'm no sure I understand it it now

I have 2 leisure ¡batteries & 2 solar panels is it worth getting an inverter....& what should I get?
 
D

Deleted member 4366

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If you're going to use an inverter, make sure that the length of the cables between the inverter and battery are as short as possible.

Bear in mind that a typical 500wh ebike battery will take about 750wh from your motorhome batteries for a complete charge, which is around 60Ah. Your leisure batteries should never be taken down past half-way, so if you had a pair of 80Ah ones, the maximum you could take from them would be 80AH if they're in tip top condition.

You'll be OK if you do a typical partial charge to top up your battery, but bear in mind that if you're off-grid somewhere, two complete charges will leave you stranded.

Personally, I'd take a small generator with me, which solves everything, and I think it's a much more sensible solution. It solves all the worry about how long you should have the lights on or watch TV as well.
 
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phil01

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Feb 4, 2017
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If you have leisure batteries fitted then I guess you would have a split charge really installed, I'd just use the invertors until the leisure battery showed a 50℅ discharge and then either simply go out for a drive to recharge the leisure battery or let it idle for an hour or so to top up the leisure battery to allow the final charge process.
I'd simply would charge my ebike battery whilst I saw either sight seeing or going out for a drive
 

Katymac

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Mar 18, 2017
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Ok total outside my capabilities; don't even understand all the words never mind how they'd all work together

It'll be the garage or my friend the electrician

Thank you so much for trying - sorry to be a doofuss!
 

Danidl

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Ok total outside my capabilities; don't even understand all the words never mind how they'd all work together

It'll be the garage or my friend the electrician

Thank you so much for trying - sorry to be a doofuss!
... In any Halfords maplins or other car accessories shop you can buy a mains adapter or inverter It takes the 12v DC from the car battery, either using crocodile clips accross the battery or using the in car cigarette lighter socket and powers a device with a single square pin mains socket. You can plug your bikes battery charger into this.unit.. The cost is reasonable. Those that use the cigarette lighter socket, are limited to about 150w of power about 10 amps from the 12v supply, those that go accross the battery could be up to 1000w. If these are used when the car motor is not running they can quickly discharge the car battery. If used when the motor is running, then no problem... The 150w unit would be drawing as much as the headlights on a normal car. You need to check in your car manual the maximum power allowed from the accessories socket... It will probably quote it in ampere or current, since the voltage in a car is fixed.Do not be tempted to replace the fuse which might be 15a with a bigger one. If you are using leisure batteries in a caravan or motor home then you could can connect accross the battery and use whatever size of wire and fuse you want. Dave's suggestion of using a short run of thick wires between the battery and the inverter is sound. Say you were to use a 500w inverter, then the current flowing at 12v into the inverter from the battery is nearly 50amps at full blast, while the voltage and current from the mains side will be 220v AC at 2amps. Once done you then have a mains socket in the caravan or motor home and it can be used for multiple applications .. TV hairdryer, etc.
 

Katymac

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Mar 18, 2017
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Visit booked to see my friend, an ex forces engineer - she will sort me out (even if she takes me by hand & escorts me to the shop!!)

Thanks guys when you need help in my specialist areas give me a shout (catering for large numbers, early years education & occasionally spreadsheets ;) )
 

D8ve

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Jan 30, 2013
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Your batteries in the camper are the limiting thing.
If they are lead acid(almost guaranteed) then they should never be more than half emptied. That kills them quickly. They usually hold about 400 watt hours of usable power each. bike batteries have similar 400 watt hour capacity ( but you can use all of it with lithium batteries).
Charge the bike once and it's OK but if your campers batteries have been used for anything lights,tv,kettle then a second charge will take your camper battery below usable limits. The battery will then have a very much shorter life span. And you might not be able to start the van :eek: with a flat battery.
If you run the camper and engine it will recharge its battery. The solar cell will help but not enough to run an electric bike as they are really power hungry.
 
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Katymac

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Mar 18, 2017
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Thanks everyone

Now I need to buy a bike cover for the back of the motorhome (& work out how to get the bikes that high up as the rack is in mid air!)
 

JohnnyGM7LSI

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Dec 5, 2016
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It might be worth looking at a Sterling Power 120 Amp Battery to Battery charger, I have one of these in my motorhome, 4X 110 Ah batteries and a 2KW inverter, I`m never without power, I might not need as much as me and get away with a smaller Battery 2 Battery charger and inverter to suit your batteries. Heres mine https://goo.gl/photos/SRjfMBNbY1Ek1Whu9
 

phil01

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Feb 4, 2017
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I have a 100ah leisure battery that I regularly discharge down to near on zero for the last 3yrs, u then recharge it and it comes back to full life everything.
A leisurely battery is a deep discharge battery and it's designed for this type of discharge.
Far too many scare stories of not allowing them to discharge below 50℅
I bet you will either sell your motor home or stop using the batteries long before they give up the ghost.
Leisure battery=deep discharge
 

Danidl

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Thanks everyone

Now I need to buy a bike cover for the back of the motorhome (& work out how to get the bikes that high up as the rack is in mid air!)
... Warning remove the battery pack and the LCD display panel , if removable before hoisting them up onto the bike rack. It will reduce the weight, making it easier to lift, and more importantly they will not fly off if you hit a bump.

Also a bike cover might be fine when the bikes are resting at night but unless they are made of a strong tarpoline will not be suitable for putting on the back of a moving van. The lightweight ones will get shredded by the literally hurricane force winds circulating around the back of a moving van. Would you wish to be responsible for such a sheet flying off on a motorway?
 

Katymac

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Mar 18, 2017
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The battery is def living inside - I'm not sure the display comes off, I'll have a look

Yes I thought some of them looked quite flimsy - can anyone recommend a tarpaulin one I can buy - with such a long trip I don't want the bike to get damaged Hythe elements
 

Danidl

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The battery is def living inside - I'm not sure the display comes off, I'll have a look

Yes I thought some of them looked quite flimsy - can anyone recommend a tarpaulin one I can buy - with such a long trip I don't want the bike to get damaged Hythe elements
My suggestion is just to put a bit of duck tape .. or gaffer tape ..Over the exposed electric contacts from the battery connection.. And maybe a shower hat over the saddle and LCD if it doesn't come off . Bikes are sturdy beasts, and the frames are either aluminium or coated steel.
 

Katymac

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Mar 18, 2017
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Oh really? You'd let them live 4 months outside?

OK I didn't think I as being over careful but if you think it's OK I won't bother with a cover

I've always kept bikes under cover before I didn't know I didn't have to
 

Danidl

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Oh really? You'd let them live 4 months outside?

OK I didn't think I as being over careful but if you think it's OK I won't bother with a cover

I've always kept bikes under cover before I didn't know I didn't have to
... Are we getting a bit sarky now? Any bike, car, etc. Will be much better protected if kept under cover. Plastics become embrittled and colours fade under exposure to UV light from sun light, iron and steel parts will rust, even stainless steel will discolour, aluminium will discolour and get a cloudy patina, painted parts will bleach. Leather does not like sunlight or downpours, mind you it does ok for years when on a cow. ...
My point was intended to cover the limited exposure of an overnight stay.
 

Katymac

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Mar 18, 2017
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Norfolk
I am sorry I really didn't mean to offend.

Totally wasn't being sarcastic; I last owned/rode a bike before my daughter was born - she is 20 this year & I honestly thought you meant that things had changed so much (you know like mobile phones have in 20yrs) that it really wasn't necessary any more

Damn that would have made my life easier

So back on the hunt for a bike cover

Gawd it's like when I was considering buying a new car (never had one before but my dad had) & I asked about 'running it in' and the salesman fell about laughing as "we don't do that anymore"
 

Danidl

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Sep 29, 2016
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I am sorry I really didn't mean to offend.

Totally wasn't being sarcastic; I last owned/rode a bike before my daughter was born - she is 20 this year & I honestly thought you meant that things had changed so much (you know like mobile phones have in 20yrs) that it really wasn't necessary any more

Damn that would have made my life easier

So back on the hunt for a bike cover

Gawd it's like when I was considering buying a new car (never had one before but my dad had) & I asked about 'running it in' and the salesman fell about laughing as "we don't do that anymore"
... Not being a car person, but. I think you were correct and the salesman was condescending. .
I was thinking that one of those blue / blue green groundsheets tarpolines with eyelets sold by aldi and the Halfords type shops for putting over trailers would be sturdy enough, provided you were prepared to scrap it whenever it started to Frey.. There are enough mounting points on the bike rack for bungee cords to make a secure. Fitting.
 

phil01

Pedelecer
Feb 4, 2017
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Dartford Kent
20170411_133238.jpg 4 year old leisure battery that I've just got out of hibernation, uses for very deep discharges as a battery I use at work to find electrical faults and jump starts, this battery is heavily abused.
I have a 100ah leisure battery that I regularly discharge down to near on zero for the last 3yrs, u then recharge it and it comes back to full life everything.
A leisurely battery is a deep discharge battery and it's designed for this type of discharge.
Far too many scare stories of not allowing them to discharge below 50℅
I bet you will either sell your motor home or stop using the batteries long before they give up the ghost.
Leisure battery=deep discharge
 

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