EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: metRo_ on March 07, 2016, 05:17:41 pm
-
Hi all,
I got a nespresso coffee machine that I want to power using a battery.
The specs are 240V @ 1200W, measured with a multimeter I got 400mA @ 235V (~100W) and it is a lot different from the 1200W. During the measurement with the multimeter I use a 5A fuse that doesn't burn. So how much of this 1200W are a safety factor and what power value should I use when choosing the battery?
Thank you
-
That sounds like the heating element never energised while you were making your measurements. Put it on a Kill-A-Watt (https://en.wikipedia.org/wiki/Kill_A_Watt) or similar and brew a couple of cups noting the peak wattage and the energy per cup brewed.
-
You do realise you can't simply connect it up to a battery and expect it to work don't you ? It requires AC.
-
That sounds like the heating element never energised while you were making your measurements. Put it on a Kill-A-Watt (https://en.wikipedia.org/wiki/Kill_A_Watt) or similar and brew a couple of cups noting the peak wattage and the energy per cup brewed.
The 400mA was measured while taking a coffe, when in standby it only draw ~20mA.
You do realise you can't simply connect it up to a battery and expect it to work don't you ? It requires AC.
I know :)
-
That sounds like the heating element never energised while you were making your measurements. Put it on a Kill-A-Watt (https://en.wikipedia.org/wiki/Kill_A_Watt) or similar and brew a couple of cups noting the peak wattage and the energy per cup brewed.
The 400mA was measured while taking a coffe, when in standby it only draw ~20mA.
When you power the Nespresso, it will start to heat the water! Did you measured the consumption when is doing this?
-
That sounds like the heating element never energised while you were making your measurements. Put it on a Kill-A-Watt (https://en.wikipedia.org/wiki/Kill_A_Watt) or similar and brew a couple of cups noting the peak wattage and the energy per cup brewed.
The 400mA was measured while taking a coffe, when in standby it only draw ~20mA.
When you power the Nespresso, it will start to heat the water! Did you measured the consumption when is doing this?
I measure but it only show an increase of 30mA. I only notice a big increase on consumption when it start to taking the coffe.
-
So your machine is already hot, the "big" (actually small) increase in consumption is just the pump, and you never measured when the heater was on. Or measured wrong.
I wonder what kind of battery (and inverter...) you plan to use. It's gonna be 3x as big as the machine, cost 4 times as much, and maybe let you make a cup or 2 before being empty....
-
Assuming you were brewing a 30ml shot of Espresso, starting with water at 20 deg C and finishing at a brewing temperature of 95 deg C, and noting that the specific heat capacity of liquid water is 4.187 J/g, it takes approx 9.42KJ to heat the water.
At your measured 235V, 400mA, the input power cannot be greater than 94W, and it is physically impossible for it to heat that volume of water in less than 100 seconds.
It *MAY* be doing cycle by cycle heat control with a 1KW heating element, which would average to a lower reading on most multimeters, but the supply would still need to be able to handle 5A peak current. If I was trying to run such a machine off batteries, I would start with a 2KW inverter off a 'house' battery bank of at least 100AH @12V on the basis that brewing 1L of coffee shouldn't deplete more than 10% of the nominal capacity.
-
Assuming you were brewing a 30ml shot of Espresso, starting with water at 20 deg C and finishing at a brewing temperature of 95 deg C, and noting that the specific heat capacity of liquid water is 4.187 J/g, it takes approx 9.42KJ to heat the water.
At your measured 235V, 400mA, the input power cannot be greater than 94W, and it is physically impossible for it to heat that volume of water in less than 100 seconds.
It *MAY* be doing cycle by cycle heat control with a 1KW heating element, which would average to a lower reading on most multimeters, but the supply would still need to be able to handle 5A peak current. If I was trying to run such a machine off batteries, I would start with a 2KW inverter off a 'house' battery bank of at least 100AH @12V on the basis that brewing 1L of coffee shouldn't deplete more than 10% of the nominal capacity.
Thank you, the "cycle by cycle heat control" make sense and should be the reason why I'm getting an average measurement on multimeter. Also the explanation about the energy needed to heat up the water will help to design the system.
-
What multimeter were you using?
What mode was it exactly in?
Would be interesting to know what meter produced that measurement...
-
What multimeter were you using?
What mode was it exactly in?
Would be interesting to know what meter produced that measurement...
The multimeter is AM-510-EUR (http://www.amprobe.com/amprobe/usen/digital-multimeters/am-500-digital-multimeter-series/amp-am-510.htm?pid=74033) on 10A Current scale
-
There's your Problem! This is not a TrueRMS Meter!
If the machine uses some sort of power control (phase cutting for example) then your waveform isn't sinusoidal anymore and the meter gives you a wrong value.
That could be the main reason of the wrong measurement.
Greetings
-
Let me tell you all a secret: You can make coffee without electricity. This is like solving how to drive a
Tesla Nissan Leaf in a country without power grid.
-
Let me tell you all a secret: You can make coffee without electricity. This is like solving how to drive a Tesla Nissan Leaf in a country without power grid.
https://www.youtube.com/watch?v=46S0JWkEXyY (https://www.youtube.com/watch?v=46S0JWkEXyY)
-
There's your Problem! This is not a TrueRMS Meter!
If the machine uses some sort of power control (phase cutting for example) then your waveform isn't sinusoidal anymore and the meter gives you a wrong value.
That could be the main reason of the wrong measurement.
Greetings
Measurement can be wrong but not tenfold wrong without the true rms.
-
Let me tell you all a secret: You can make coffee without electricity. This is like solving how to drive a Tesla Nissan Leaf in a country without power grid.
:palm:
-
Let me tell you all a secret: You can make coffee without electricity. This is like solving how to drive a Tesla Nissan Leaf in a country without power grid.
Also the plastic pod things the Nespresso uses are filling up landfill sites at such a rate that the bloke who invented it has publicly regretted ever doing it.
http://www.independent.co.uk/life-style/food-and-drink/news/inventor-of-the-coffee-capsule-feels-bad-for-environmental-damage-and-prefers-to-use-filters-10083379.html (http://www.independent.co.uk/life-style/food-and-drink/news/inventor-of-the-coffee-capsule-feels-bad-for-environmental-damage-and-prefers-to-use-filters-10083379.html)
-
I looked into this four years ago, I wanted a (mobile) Nespresso in the car.
Biggest problem was for the aprox. 1000W you need the 12V->230V DC-AC converter is pretty costly and the battery should provide 83 amps :o
Scrapped the project and realised this is probably the reason there are no cars with an nespresso machine built in :)
-
Anyone who's into sail/power cruising or RV/caravanning has encountered the problem of "How can I run <appliance X> from batteries?". Alternatives to the appliance you are familiar with may be uneconomic, have a higher running cost or produce an inferior result, hence your desire to run the actual appliance. Often the right answer is "Forget about it!" but unless you do the analysis properly, you don't *KNOW* that, and it may have benefitsthat make it worthwhile, or you may be able to share the battery/inverter system with other appliances, that make it economic to do albeit very expensive. e.g. a friend bought a boat that the previous owner had installed a 1KW Microwave on. The power budget to run it for 5 minutes was frankly insane as it drew about 100A at 12V through the inverter, and for battery operation would have required either replacing their house bank with 'leisure' batteries with a CCA rating, with considerable loss of available capacity and lifespan, or doubling its capacity, and replacing the charger and alternator. Their original intention was to rip it out and regain the locker space, but their first trip was in absolutely horrible weather and it turns out that it earns its keep in bad weather to heat pre-prepared, pre-packed individual portion meals for the crew, when its too rough to cook safely and you are either motor-sailing anyway or are willing to run the engine, adjust sail and maybe even alter course to stabilise the boat to serve a meal, so as long as the engine revs are high enough, battery capacity isn't problem. Its also handy in harbour with shore-power available, for convenience or when entertaining to off-load some dishes from the limited galley stove capacity.
The 1200W rating is likely to be the maximum possible instantaneous power including initial inrush current for the control electronics.
Maximum actual power consumption is likely to occur if if the machine is doing a 110 ml lungo (long) pour starting from cold at a low room temperature.
@_metRo,
What sort of battery installation did you have in mind? I doubt a 'man portable' solution would be practical.
What test equipment do you have available to measure (and preferably log) the true power and check for waveform distortion that might upset an inverter. E.g. if you have a 2 channel or better DSO that can either do waveform maths and averaging, or can save captured waveforms in a format that can be transferred to a PC, then all we have to do is figure out how you can hook it up safely.
-
I looked into this four years ago, I wanted a (mobile) Nespresso in the car.
Biggest problem was for the aprox. 1000W you need the 12V->230V DC-AC converter is pretty costly and the battery should provide 83 amps :o
Scrapped the project and realised this is probably the reason there are no cars with an nespresso machine built in :)
I work for a company who builds the electronics for coffee machines and I know for a fact that we don't use the 230VAC anywhere. We use 24VDC for the high power stuff such as heaters and motors.
So you would be fine if you can buy a 12V->24V converter and then you would ony have to open the Nespresso machine and find output of the PSU. (Of course you would do it the other way around, first you search the output of the PSU and meassure it and then you buy a converter with the same voltage).
If you are interested, we build the electronics for Eversys (https://www.eversys.com/ (https://www.eversys.com/)) and they assemble the machines.
Edit:
I also cannot believe that the Nespresso uses 1kW. If I am not misstaken the small Eversys e'2 machine needs 200W. I will look it up tomorrow.
The Heater and the motor of the Nespresso Essenza are 230V in Europe. The Logic board, uses a PIC micro, with a transformless power suply.
-
Right now what I have in mind is a 6S 20000mAh Multi-Rotor Lipo Pack and a 1200W Inverter (http://energenie.com/item.aspx?id=5986)
It will be used on a marketing show to brew some coffes, the show will last half an hour and only one time.
I could disassemble the machine to look into it but it'll take some time but someone else can confirm that it is indeed a 24V device inside...
BTW I have access to an oscilloscope but the I don't have any resistor with needed power dissipation.
-
Right now what I have in mind is a 6S 20000mAh Multi-Rotor Lipo Pack and a 1200W Inverter (http://energenie.com/item.aspx?id=5986)
It will be used on a marketing show to brew some coffes, the show will last half an hour and only one time.
I could disassemble the machine to look into it but it'll take some time but someone else can confirm that it is indeed a 24V device inside...
BTW I have access to an oscilloscope but the I don't have any resistor with needed power dissipation.
Like i already answer above, the Nespresso Heaters and pumps are 230V in Europe, and the logic board uses a transformless power supply. Both Heater and pump are controlled by 2 triacs.
If you search google, you will confirm what i'm saying.
-
OK, so you just need a quick&dirty solution. That inverter will *probably* cope if the Nespresso transformerless power supply survives its modified 'sine' output waveform (which is far from certain) Due to the high 3rd harmonic content of a modified 'sine' wave, it may blow the shunt regulator in a capacitive dropper PSU.
However, unless I owned a 24V truck and also needed the LiPO pack for another use, for a 1-off event, I'd simply get a 12V pure sine inverter with an adequate rating and use it off the starting battery borrowed from my vehicle. If its in good condition and you don't use more than 20% of the nominal capacity, you shouldn't have any problems starting the vehicle afterwards, and if you drive for at least 1/2H it should be close to fully recharged. Figure on about 10AH at 12V for a litre of brew.
-
OK, so you just need a quick&dirty solution. That inverter will *probably* cope if the Nespresso transformerless power supply survives its modified 'sine' output waveform (which is far from certain) Due to the high 3rd harmonic content of a modified 'sine' wave, it may blow the shunt regulator in a capacitive dropper PSU.
Actually, it's not the first time that i see the logic board burned. And yes, it is a capacitive X2 transformless PSU
Some random google images attached!
-
Right now what I have in mind is a 6S 20000mAh Multi-Rotor Lipo Pack and a 1200W Inverter (http://energenie.com/item.aspx?id=5986)
If you don't discharge the battery completely it should be possible to brew 4 liters of coffee with the available energy.
That equals about 133 espressos or 40 normal coffees.
Now you need to know if that's enough.
Greetings
-
I wonder what kind of battery (and inverter...) you plan to use. It's gonna be 3x as big as the machine, cost 4 times as much, and maybe let you make a cup or 2 before being empty....
I imagine the Americans solved the problem of making fresh coffee in space before they'd even built a rocket.
http://www.nasa.gov/mission_pages/station/research/experiments/1769.html (http://www.nasa.gov/mission_pages/station/research/experiments/1769.html)
Priorities man, priorities
O0
-
That inverter is only specced to work down to 21V. On a 6S LiPO pack that's 3.5V per cell so only about 2/3 the nominal capacity. That means you only have about 1MJ theoretically available, or 3.3l of water heated 75 deg C. Best case, you'll probably have 10% losses each in the battery, inverter and Nespresso, so you'll be lucky to see over 2.4L brewed. It could be as little as half that, i.e 10 longo or 40 espresso.
Caution: At most exhibitions, exhibitors cannot offer anything except pre-packaged, non-perishable food/drink to the general public without a food hygiene assessment. Check the venue's regulations carefully *BEFORE* dispensing beverages.
-
Where did the post below go to? It dissapeared? Is the forum corrupt or did some admin remove it? :o
I looked into this four years ago, I wanted a (mobile) Nespresso in the car.
Biggest problem was for the aprox. 1000W you need the 12V->230V DC-AC converter is pretty costly and the battery should provide 83 amps :o
Scrapped the project and realised this is probably the reason there are no cars with an nespresso machine built in :)
I work for a company who builds the electronics for coffee machines and I know for a fact that we don't use the 230VAC anywhere. We use 24VDC for the high power stuff such as heaters and motors.
So you would be fine if you can buy a 12V->24V converter and then you would ony have to open the Nespresso machine and find output of the PSU. (Of course you would do it the other way around, first you search the output of the PSU and meassure it and then you buy a converter with the same voltage).
If you are interested, we build the electronics for Eversys (https://www.eversys.com/ (https://www.eversys.com/)) and they assemble the machines.
Edit:
I also cannot believe that the Nespresso uses 1kW. If I am not misstaken the small Eversys e'2 machine needs 200W. I will look it up tomorrow.
-
Where did the post below go to? It dissapeared? Is the forum corrupt or did some admin remove it? :o
I looked into this four years ago, I wanted a (mobile) Nespresso in the car.
Biggest problem was for the aprox. 1000W you need the 12V->230V DC-AC converter is pretty costly and the battery should provide 83 amps :o
Scrapped the project and realised this is probably the reason there are no cars with an nespresso machine built in :)
I work for a company who builds the electronics for coffee machines and I know for a fact that we don't use the 230VAC anywhere. We use 24VDC for the high power stuff such as heaters and motors.
So you would be fine if you can buy a 12V->24V converter and then you would ony have to open the Nespresso machine and find output of the PSU. (Of course you would do it the other way around, first you search the output of the PSU and meassure it and then you buy a converter with the same voltage).
If you are interested, we build the electronics for Eversys (https://www.eversys.com/ (https://www.eversys.com/)) and they assemble the machines.
Edit:
I also cannot believe that the Nespresso uses 1kW. If I am not misstaken the small Eversys e'2 machine needs 200W. I will look it up tomorrow.
Sounds dubious, either way. Why the hell would Nestlé outsource the machines to Krups and DeLonghi only for them outsource them again to Eversys?
-
OK, so you just need a quick&dirty solution. That inverter will *probably* cope if the Nespresso transformerless power supply survives its modified 'sine' output waveform (which is far from certain) Due to the high 3rd harmonic content of a modified 'sine' wave, it may blow the shunt regulator in a capacitive dropper PSU.
However, unless I owned a 24V truck and also needed the LiPO pack for another use, for a 1-off event, I'd simply get a 12V pure sine inverter with an adequate rating and use it off the starting battery borrowed from my vehicle. If its in good condition and you don't use more than 20% of the nominal capacity, you shouldn't have any problems starting the vehicle afterwards, and if you drive for at least 1/2H it should be close to fully recharged. Figure on about 10AH at 12V for a litre of brew.
Do you think the chances of damage the machine are high?
I never say I will use it on a truck. I need it to be "portable".
I choose a 24V inverter trying to get a little more efficiency. I didn't find a pure sine inverter from a local store here in Portugal with proper power rating. I'll appreciate if someone could advice an European store with good prices that could ship it quickly.
-
I bought the inverter: 12V 1200W. With a lead-acid battery of 12V @ 33Ah I was able to brew 30 expressos and the battery still have some joice for more :-+
-
Great. The only disadvantage of a lead acid battery is it needs to be charged as soon as possible after use, and regularly recharged when in long term storage. OTOH its a far cheaper way of buying V*AH than a high capacity LiPO pack. If you leave it heavily discharged it can die in as little as 24H in hot weather, so don't do that, and preferably don't use more than 2/3 its nominal capacity.
-
The Heater and the motor of the Nespresso Essenza are 230V in Europe. The Logic board, uses a PIC micro, with a transformless power suply.
Yeah I realised it 2min after I wrote my post (this is wh I deleted it, it was missleading).
I remembered that we have a Nespresso machine lying around. As soon as I looked atthe striped down machine I knew that I just wrote crap xD
Still, I don't you actually need 1kW. It will just take longer to heat up but that isn't really a problem (I assume).