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Hi

I am looking at purchasing and running a drinks cooling machine to run on no mains electric what so ever!



The company that sells the machine have advised the following

Frequency: 50Hz Rated current: 5.5A Rated input: 800W



This machine is a liquid to liquid based (water and anti freeze bath) heat exchange and only runs when liquid is passing though it. And will only operate when I open the tap and fill a glass up from it so it will not be running most of the time



The two option I am considering is buying a generator inverter and battery and charging the battery up as required. Or just running the generator when it is in operation. So what do you think?



Thanks
 
Looking after a generator is a pain, but presumably you don't have the options for that much power otherwise.

If it is a drinks machine you probably want as little noise as possible, so look for that in any specification as it might pay for a slightly bigger model that has a better silencer, etc.

Leaving generators running on no/light load is not good for them, especially diesel type (search for "wet stacking") so if you have the budget, space and transport (if necessary) then running a generator for short periods at high load to charge a large car/lorry/boat battery and then running your kit off an inverter from that might be better overall, even if the initial cost is a bit higher.
 
Is this for events use?
 
Does this use compressor refrigeration? Your description suggests not, but if it does, allow for a compressor starting load of 3-5 times the running load. This is quite critical especially if it is designed to start against remaining head pressure. With an undersized generator or inverter if the compressor stalls and trips its thermal protection, it might not then be able to restart for a further 5 minutes. Also, if the load on a small generator is mostly from an induction motor, a self-regulating alternator will tend to drop out of voltage regulation due to the low power factor. An inverter generator or one with a proper AVR is beneficial.

Can you post or link to the machine specs?
 
yes it is
OK, I thought as much. Be aware that for a variety of reasons most event sites expressly forbid 'private' generators and insist that if you need power then it's provided by the event electricians (aka 'hook-up'). So before you spend anything I'd strongly suggest doing your homework on that aspect first. I say this as an experienced events electrician!
 
Hi

I am looking at purchasing and running a drinks cooling machine to run on no mains electric what so ever!



The company that sells the machine have advised the following

Frequency: 50Hz Rated current: 5.5A Rated input: 800W



This machine is a liquid to liquid based (water and anti freeze bath) heat exchange and only runs when liquid is passing though it. And will only operate when I open the tap and fill a glass up from it so it will not be running most of the time



The two option I am considering is buying a generator inverter and battery and charging the battery up as required. Or just running the generator when it is in operation. So what do you think?



Thanks
May I ask you to amplify what ‘drinks’ you want to ‘cool’? What form do the drinks have before the need to cool? Could you also say something about a typical day’s business selling these cooled drinks: How many in total? What volumetric quantity is each drink? What rate of sale? How many days per week, per month, per year?

and do want to keep already cool drinks cool or to cool drinks which presale are at ambient temperature?
 
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OK, I thought as much. Be aware that for a variety of reasons most event sites expressly forbid 'private' generators and insist that if you need power then it's provided by the event electricians (aka 'hook-up'). So before you spend anything I'd strongly suggest doing your homework on that aspect first. I say this as an experienced events electrician!
sorry there is no chance of mains, but I will need a fairly silent generator like a Honda due to noise to local residents
 
May I ask you to amplify what ‘drinks’ you want to ‘cool’? What form do the drinks have before the need to cool? Could you also say something about a typical day’s business selling these cooled drinks: How many in total? What volumetric quantity is each drink? What rate of sale? How many days per week, per month, per year?

and do want to keep already cool drinks cool or to cool drinks which presale are at ambient temperature?
They are 11 kegs of beer that a forced out of the keg (at room temrature) by C02 and into the drinks cooler

To be used all weekend
 
Hi,i have done a similar project for a pal,and on assessment,we worked out the following....

You will not want a geny running full time,for sporadic use,and you will not want to start a geny,string or buttton,on every need...

Add to that the extra issues of fuel,security and reliability,and we plumbed for bank of 4 deep cycle batteries paralleled up to an inverter.

These were mounted in a cradle underneath the trailer,and charged up at base,and i believe we had to over spec the inverter,but it worked ok.

You may need to find out some details regarding the start current,running load,and cycle pattern of your chiller,in order to plan an accurate choice of useable stored power,remembering minimum voltage requirements,standby losses,etc.


Just to cheer you up,if you opt for a small,quiet generator,in the scenario described,get two....

If you don't have theft or a breakdown in the first dozen outings....it'll be a first?
 
Hi,i have done a similar project for a pal,and on assessment,we worked out the following....

You will not want a geny running full time,for sporadic use,and you will not want to start a geny,string or buttton,on every need...

Add to that the extra issues of fuel,security and reliability,and we plumbed for bank of 4 deep cycle batteries paralleled up to an inverter.
Where you running a drinks chiller? What kind of drinks where you doing?
Can you recomend any batteries; As they all very in size. What size inverter did you have?
Thanks
 
I designed a system to power 20 odd catering vans, each with chest freezer, 2 tall larder fridges, lighting and payment system using solar power Mar-Oct - and on peak solar days in summer a 1kW hand hot water heater. Other times a Honda engined 3.4kVA LPG generator with automatic voltage regulator provides van power during opening hours and charges the batteries for overnight use.

This is the robust 3kW inverter which has a very high peak power capability (9kW), pure sinewave and 'sleep' mode when load drops below 75W and wake up when load rises above this figure which conserves battery power.

12V solar panels charging kits for caravans, motorhomes, boats, yachts, marine - https://www.photonicuniverse.com/en/catalog/full/164-3000W-24V-low-frequency-pure-sine-wave-off-grid-inverter-peak-power-9000W.html

Batteries are Advanced Gel Matrix by Victron:

12V solar panels charging kits for caravans, motorhomes, boats, yachts, marine - https://www.photonicuniverse.com/en/catalog/full/470-200Ah-12V-Gel-deep-cycle-battery-for-motorhomes-caravans-boats-and-off-grid-power-systems.html

Either 6 x 200Ah or 4 x 300Ah, wired in strings of 2 batteries in series to give 24V and these then connected in parallel. The theoretical power available from fully charged to batteries 'flat' is 12 x 1200 = 14.4kWh but this is not achieved nor relied upon. Instead the batteries are never discharged more than 50% to preserve their life; thus about 7kWh is the working amount of electrical energy available.

7kWh would run an 800W cooler constantly for 7000/800 = about 9 hours.

This system is static apart from when the catering van is driven to and from site for its annual maintenance and refurbishment - the electrical wiring and electronics is only shaken about for a few hours each year. Of 20 vans we have only had one inverter failure which was on arrival not when in use and the supplier replaced it.

Don't operate at 12V. Use 24V and the cabling must be multi-stranded with properly crimped on ring terminals tightly bolted. One needs to buy a hydraulic crimper tool.

The amount of energy stored in each battery and then as a bank is extraordinarily high and it is highly dangerous if a battery or the bank is short circuited or if there is a fault current. Circuit breakers are essential and the battery must be located in an lockable enclosure. Special precautions, insulated tools and personal protective equipment are required when connecting up the batteries and high current 24 V cabling: this is a job for a skilled person. I wrote a procedure to do this which is followed to the letter.

The flat roof of the catering vans has a 1.5kW array of solar voltaic panels to charge the batteries.

On the mains voltage side everything has to be done to meet the IET electrical installation regulations and my client (brother in law) has to have annual certificates for inspection and testing including PAT of the electrical items for him to operate. We include the 24V dc and the solar photovoltaic wiring in the inspection and testing since it too can kill or harm just as much as the 240V.

I will not say more because I do not want to design your working safe system. There are safety features and programming of the inverter to do for the intended application. I suggest you contact Tom at Photonics Universe for further advice and an electrician familiar with off-grid battery to mains installations. I strongly advise against doing it yourself because you are not competent and do not know how to deal with all the risks.

PS: I am not saying this set up will satisfy your requirement. I have not done the analysis which should include whether you would be wiser to just use a generator to meet the business and operational requirement as distinct from the technical requirement.
 
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I should have said that there was a business requirement for constant availability of power 24/7/365 in the application I mentioned.
 
Just to add for the OP that "you are not competent" has a specific meaning in terms of electrical regulations. They divide people in to electrically skilled and competent (i.e. trained electricians and the like) who can be expected to work safely on electrical systems, and the rest of the population.

It has nothing to do with your competence in any other aspect of life!
 
I designed a system to power 20 odd catering vans, each with chest freezer, 2 tall larder fridges, lighting and payment system using solar power Mar-Oct - and on peak solar days in summer a 1kW hand hot water heater. Other times a Honda engined 3.4kVA LPG generator with automatic voltage regulator provides van power during opening hours and charges the batteries for overnight use.

This is the robust 3kW inverter which has a very high peak power capability (9kW), pure sinewave and 'sleep' mode when load drops below 75W and wake up when load rises above this figure which conserves battery power.

12V solar panels charging kits for caravans, motorhomes, boats, yachts, marine - https://www.photonicuniverse.com/en/catalog/full/164-3000W-24V-low-frequency-pure-sine-wave-off-grid-inverter-peak-power-9000W.html

Batteries are Advanced Gel Matrix by Victron:

12V solar panels charging kits for caravans, motorhomes, boats, yachts, marine - https://www.photonicuniverse.com/en/catalog/full/470-200Ah-12V-Gel-deep-cycle-battery-for-motorhomes-caravans-boats-and-off-grid-power-systems.html

Either 6 x 200Ah or 4 x 300Ah, wired in strings of 2 batteries in series to give 24V and these then connected in parallel. The theoretical power available from fully charged to batteries 'flat' is 12 x 1200 = 14.4kWh but this is not achieved nor relied upon. Instead the batteries are never discharged more than 50% to preserve their life; thus about 7kWh is the working amount of electrical energy available.

7kWh would run an 800W cooler constantly for 7000/800 = about 9 hours.
Did you use all of that set up to power all of the vans at once?
 
No, poor writing. Each van had an installation since the fleet of them is dispersed around England. I tried to persuade my client/BIL to use Honda inverter generators but he continued with the conventional Honda GX engined frame generators because he and his team knew them so well and had a maintenance and repair set-up for them already. It is the engine which fails not the alternator. My BIL changes engines and sets them up to start and run correctly.

Generators are attractive items to 'certain' folk and are easily stolen unless solidly chained to something immovable or built in to the structure. Overnight or when unattended, if not built in to the structure behind a very strong locked door (obviously when shut down) or if left chained up outside they will soon disappear.
 

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