Inverter - Size?

Miss Trinity

Miss Trinity

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I'm looking at getting a Lithium battery with invertor set-up in my wagon but am not sure what size I might need to run bike charger, variouz tech, microwave and hair-dryer no less. Might as well cover all my options. So is 1500w adequate or 2000w sine-wave my best bet. Would appreciate ya thoughts and experiences, cheers Trinity =",'=
 
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Miss Trinity said:
I'm looking at getting a Lithium battery with invertor set-up in my wagon but am not sure what size I might need to run bike charger, variouz tech, microwave and hair-dryer no less. Might as well cover all my options. So is 1500w adequate or 2000w sine-wave my best bet. Would appreciate ya thoughts and experiences, cheers Trinity =",'=
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Whilst Miss Trinity is asking unbelievably important questions .................... same scenario no hair dryer and no microwave answers please.
 
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Not all hair dryers are created equal. The better, more powerful the dryer the more energy it takes. Microwaves, rule of thumb is at least twice the rated wattage, as it draws that on startup
 
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2000 with a surge of 4000 minimum or even 3-6 for the microwave.
Plenty of lithium, 200 ah minimum 3-400 best and as much solar as you can fit, plus b2b

get a 700w microwave dont go billy big boy,
 
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There are soft start microwaves available. Ours is a quite old Quest 550 or 6oowatt. On the meter it starts at quite low wattage and ramps up to just over 900watts during cooking.

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For a small microwave a 1500 w inverter should be OK pro iding you get a decent one like a Victron, cheap ones tend to fall over on the microwave start up current. Hairdryer you can size to the inverter.
You are going to need 200ah of Lithium to run it.
 
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Yay, cheers all. Some very insightful info. Much as i had figured. And thankfully I already have 200w of Solar Am getting 200Ah Lithium with 50A B2B charger. I realise anything is possible if ya have the cash, but trying to make the best on my wee budget. Thanks again =",'= Trinity
 
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Do ensure the inverter is "Pure Sine Wave" electronics in many bits of kit won't like some of the cheaper ways it will work.

Your battery(s) will have a maximum rate of discharge (current load). That is different to the capacity of the battery. The wattage of your inverter may be limited by this. Lithiums usually support a higher discharge rate than more traditional batteries but you'll need to check the specs.
 
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Miss Trinity said:
Yay, cheers all. Some very insightful info. Much as i had figured. And thankfully I already have 200w of Solar Am getting 200Ah Lithium with 50A B2B charger. I realise anything is possible if ya have the cash, but trying to make the best on my wee budget. Thanks again =",'= Trinity
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Sounds like you are on the right track..think about more solar when you can afford it esp if you don't drive each day to replen the lithium..
Good luck
 
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Miss Trinity said:
but am not sure what size I might need to run bike charger, variouz tech, microwave and hair-dryer
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Various tech is a bit vague, but most laptop/phone chargers are 100W or less. A 150W PSW inverter will do for them. It will run from a standard leisure battery, and you could even get away with running it from a cigarette-lighter 12V socket.

A bike battery is about 500Wh and charges in 2 or 3 hours, so a 300W inverter will be OK for that. It will need to be wired directly to the battery, via a fuse, maybe 30A or 50A. 500Wh from a 12V battery is 500/12 = 42Ah, which is a large part of a 100Ah standard leisure battery, so you need to be thinking of how to recharge the leisure battery (solar, B2B etc). 300W from a 12V battery is 300/12 = 25A, which is about the maximum you can take from a 100Ah lead-acid battery without too much damage. If it's lithium it should be OK.

A microwave and/or hairdryer needs an inverter over 1000W, and is a more serious installation. It needs thick wires direct to the battery, as short as possible, with a Midi or Mega fuse. You'd be better looking from the point of view of fitting a 1500W inverter, then buying the microwave and hairdryer that is within that power limitation. It gets progressively more expensive if you want more power, you need more batteries, a bigger B2B, a bigger mains charger, as much solar as will fit, you get the idea. A 1500W inverter takes 125A, plus a bit for inefficiencies, so ideally that needs 200 to 300Ah of lithium battery, or 600Ah of lead-acid battery.

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Wow, that certainly covered the bulk of my concerns. Tis much appreciated pet thank you x:-) And yes I'm heading down the lithium route 200Ah, with B2B charger. I am wondering whether a 75A B2B would be better than 50A as I tend not to move far between stop-overs and always off-grid so am concerned about topping-up the lithium sufficiently enough each day. As it hastp be replaced somehow. The weight reduction will also help too =",'=
 
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I have a 600w microwave, which is the most powerful thing I run. That sucks close to 70amps when running, so lithiums are a must. It's actual power demand is 1Kw. so I have a 1500W PSW inverter to provide a bit of spare capacity. The 12v side is 2 x120 lithiums and 3x100w panels in series.
 
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Just double check your alternator will take the extra B2B amps, More is always better but you don’t want to overheat your alternator either.
 
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Microwave via inverter is double the wattage rating of the inverter, and not just during start up. Pure Sine Wave always. Make sure your lithium BMS is rated at least 150A. And hair dryers are called towels!!
 
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Miss Trinity said:
I'm looking at getting a Lithium battery with invertor set-up in my wagon but am not sure what size I might need to run bike charger, variouz tech, microwave and hair-dryer no less. Might as well cover all my options. So is 1500w adequate or 2000w sine-wave my best bet. Would appreciate ya thoughts and experiences, cheers Trinity =",'=
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i have been using a 1200watt microwave for about 10years/powered by a 100ah huawei sealed lead acid battery/the invertor peak is 3,000watts which can deliver a constant 1500watts constant running/the microwave is usually only run around 4mins max /this covers a cup of water for tea/scrambled egg ect small micro meal/battery recovers easily from 150watt solar panel/obviously these are not big meals/but enough for a simple life/However the current involved is 100Amps/req heavy duty cable and short at that from battery to invertor/ the microwave output is a very good return @ 800watts using a low power micro wont save you any power as it will be on longer ( pure sine wave invertors are better for electrical items that may be fussy and thats about it)mine are not n never had any problems. WARNING microwave ovens require earthing of the high voltage transformer to ensure correct operation/ and safety THEY GO ALL TINGLY / A trip socket will not provide this on its own(it will only work if power is coming from a mains supply)(invertor power is self generated)//You need an open circuit (EARTH RETURN)(microwave n van earthed together) / You need to fit a current operated ELCB(RCB) . IF YOU DONT HAVE A BIG Nasty microwave then your fine JUST ABOUT EVERYTHING ELSE YOU COULD USE IN YOUR CAMPER WILL BE DOUBLE INSULATED AND WONT TAKE MUCH POWER AT ALL.so everything can stay in a closed circuit ie no earthing
 
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fronkyfronk said:
i have been using a 1200watt microwave for about 10years/powered by a 100ah huawei sealed lead acid battery/the invertor peak is 3,000watts which can deliver a constant 1500watts constant running/the microwave is usually only run around 4mins max /this covers a cup of water for tea/scrambled egg ect small micro meal/battery recovers easily from 150watt solar panel/obviously these are not big meals/but enough for a simple life/However the current involved is 100Amps/req heavy duty cable and short at that from battery to invertor/ the microwave output is a very good return @ 800watts using a low power micro wont save you any power as it will be on longer ( pure sine wave invertors are better for electrical items that may be fussy and thats about it)mine are not n never had any problems. WARNING microwave ovens require earthing of the high voltage transformer to ensure correct operation/ and safety THEY GO ALL TINGLY / A trip socket will not provide this on its own(it will only work if power is coming from a mains supply)(invertor power is self generated)//You need an open circuit (EARTH RETURN)(microwave n van earthed together) / You need to fit a current operated ELCB(RCB) . IF YOU DONT HAVE A BIG Nasty microwave then your fine JUST ABOUT EVERYTHING ELSE YOU COULD USE IN YOUR CAMPER WILL BE DOUBLE INSULATED AND WONT TAKE MUCH POWER AT ALL.so everything can stay in a closed circuit ie no earthing
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Does the van need earthing since it's on rubber tyres?! 🤔🤔🤔
 
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Beyond belief, 100a draw out of 100a sealed Pb, 1C and lasted 10 years. I must of bought wrong batteries. I have rolls surrette on 6th winter now, and I don’t think they will be very strong for the next one. Never exceeded C/8 charge or discharge, always serviced regularly as per Rolls manual, and all logged for the past 6 years. Warranty is under a year remaining. Am I missing something here?
 
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HUAWEI OT100-12L battery cost me about £150 from Tanya batteries/now have new van (bought for covid)still got this battery as a spare/has lost %/its near enough retired/but did perform outstandingly for at least 8years always connected to my solar panel/did price new the same but price was £300/managed to get a 67kg 200ah silver gel deep cycle as a replacement for around £350/personally think a lead acid battery is probably best for a micro as similar usage ie starting a car big amps short periods.this battery would seem to prove the point

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Our 800W microwave has an input power of 1250W.
We have a 1500W pure sine wave inverter and it runs the microwave with problem.
 
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If pennies are short of supply, have you compared the cost of a 'proper' installation with that of paying for meals and going to a hairdresser instead? There's more than one way to skin a cat and your payload could be improved by not overloading your van with gadgets.
 
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