# Inverter and batteries for coffee van



## Féte

Hi just wondering is any one can help me. 
we run a coffee van which we use an Generator atm and mains power but we are looking at getting an inverter and running it off 12v batteries. I'm just wondering if any one can help or Recommend batteries and inverters. Our coffee Machine is duel fuel so runs off gas so there's not much being pulled from that a mazzer major grinder which is about 850 I think fridge , freezer and flow jet water pump and lights but there only led

we are running around 2500 watts at one time

thanks in advance for your help


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## SDM

First you need to work out how many Amp hours of battery capacity you are going to need. Amps = Watts / Volts. Look at how many hours everything is going to be running for and how you are planning to charge the batteries. The fridge/freezer may only be running around 20% of the time, depending on the model. If the van is regularly driving long distances, charging the battery off the alternator is simple and cheap to set up. If you are going to be using it in the same place for a while without driving long distance or having a mains supply, you are going to need to charge the batteries by the generator or some other means (e.g solar).

If you go for a lead acid or AGM battery, you will kill the battery if you discharge it more than 50%. You don't really want to be discharging more than 30% regularly so you'll have to size your capacity accordingly.

If you get a LiFePO4 battery, you can use close to the full capacity without damage. On the downside, you must keep the battery above 0°C at all times when charging or discharging or you'll damage the battery. Also, they are a lot more expensive to purchase but also smaller and lighter.

For the inverter, work out what your peak wattage is going to be, then build in a bit of spare capacity. Expect the inverter to be about 90% efficient. The peak wattage of some appliances when starting up may be a lot higher than the continuous wattage so make sure you plan for the peak. Make sure you get a pure sine inverter rather than a modified wave inverter if you plan to use any sensitive appliances. This may include grinders, I'm not sure. There are lots of reports of cheap inverters failing well below their stated wattage or breaking after a few months.

I use an Edecoa pure sine wave inverter in my campervan and have been happy with it but my use is very different to yours so I can't really offer advice on specific inverter or battery models for you. In normal use, I run a grinder a few times a day, some LED lights, charge a laptop, phones, speakers and a few other bits and bobs. I also have solar panels and can charge off the alternator so I don't really have to worry about running out of charge (I don't have a mains hookup). I have also run drills, jigsaws, circular saws and sanders off it with no problems.

Don't forget to make sure all your wiring, fuses etc are also up to the job. You'll probably also want a suitable charge controller with something to monitor your battery levels and input/output.

The guys over at www.12voltplanet.co.uk are always really helpful at talking through which options would be best suited to your needs. There are cheaper shops though. Self build campervan forums and guides are useful too.

Hope some of that was helpful, apologies if it's teaching you to suck eggs.


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## Féte

Hi thanks for you reply!

im thinking I'm going to need a 2000w to 4000w peak I've worked out I will be running around 2500 watts on and off for around 3/4 hours a day what would the best ah battery's be that could handle that time frame with out dining one me

ive been looking everywhere 

thanks


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## BlackCatCoffee

I have a similar set up with a dual fuel machine. I use a leisure battery manufactured by Leoch. I think it is 150 amp hour of the top of my head.

It works well although I only run the machine and grinder from it so I will not have as high of a draw as you will.

I made the mistake of buying a cheap inverter and cheap charger. Big mistake they soon failed.

Just pay up and look big for the good stuff first time around! It will be less expensive in the long run.

SDM has given you some great advice, perhaps speak to the company he suggested and get them to spec up a system for you. They will know exactly what is what.


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## thesmartcoffeeco

I've just set up and have a dual fuel machine. I'm trying to work out the power requirements, the machine is 3000W but we will use as dual fuel so I expect the machine to be using a lot less power. I'm not sure how much to factor into my calculations though, Black Cat Coffee - what do you factor in?


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## thesmartcoffeeco

Do you also run a flojet pump from your battery/inverter too?


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## BlackCatCoffee

thesmartcoffeeco said:


> I've just set up and have a dual fuel machine. I'm trying to work out the power requirements, the machine is 3000W but we will use as dual fuel so I expect the machine to be using a lot less power. I'm not sure how much to factor into my calculations though, Black Cat Coffee - what do you factor in?


 The machine does not draw an enormous amount when on gas, perhaps 50w. The Flojet draws 50w. The machine pump top out at 300w then factor your grinder, mine is a Compak K6 and is 240w.

Total 640w.

Plus some overhead.

We went with a 1000w continuous 2000w peak inverter.

After our initial crappy quality inverter died we haven't had any problems with this specification using quality stuff.


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## thesmartcoffeeco

thanks so so much that's really helpful.

when you say the machine only draws 50w when on gas - do you mean when it is stationary and not in use? then additional 300w when in use?

have you factored in 640w being at total capacity? as opposed to using a % based calculation depending on when the machines are in use?

what battery do you use with the inverter?


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## BlackCatCoffee

thesmartcoffeeco said:


> thanks so so much that's really helpful.
> 
> when you say the machine only draws 50w when on gas - do you mean when it is stationary and not in use? then additional 300w when in use?
> 
> have you factored in 640w being at total capacity? as opposed to using a % based calculation depending on when the machines are in use?
> 
> what battery do you use with the inverter?


 The machine draws very little when on but idle say 50w. When running on gas all the machine draws is power for the pcb, solenoids and flow meters so not a lot. The 300w figure is for when the pump kicks in and the machine is brewing or refilling the boiler.

640w is for me my total possible draw. I cannot comment what yours will be as you would need to find the wattage of your grinder.

I use a Leoch LAGM 130 battery.

Perhaps have a chat with some specialist who can properly advise you. You do not want to end up with stuff that is unsuitable.


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## thesmartcoffeeco

yes i will do! how long does your battery tend to last?


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## PB2388

You really do need to work out your daily amp draw to calculate the size of the battery bank you will require. SDM's info is solid and the 30% he recommends for discharge on AGM's over a day is sound advice if you dont want to damage your batteries. However that requires you to have a sizeable battery bank. Straight off the bat you need to be running a duel fuel machine like a Fracino. Two heads draws I believe 350W. Tack on lights, fridge, grinder, flowjet and perhaps a couple of other bits and bobs and you are up to 50AH. Its no good calculating standby loads, the name of the game is making and selling coffee and to do this you are going to need a large battery bank to ensure that your system doesnt grind to a halt after a couple of hours. Lithium batteries are the way to go but are expensive. When starting out an option maybe is to consider running batteries when you are not very busy and then switch to a generator when the crowds show up. Most Duel fuel setups will run comfortably on a Honda 2.2 silent generator especially if you have designed it for a battery setup. That can also charge your batteries when its running. Like all appliences buy the best you can afford. If you buy a cheap generator expect unreliable performance, believe me there is nothing more frustrating than having people who want to buy coffee from you but you cant make it because your system has gone down.


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