AC Fridge In Campervan -.Power Consumption Test

[wildebus]

It is a matter of horses for courses when it comes to anything to do with a Motorhome - and that applies to the "best" type of fridge just like it depends on the type of vehicle and everything else. If you want to be hooked up every other day, you don't need to bother with Solar. If you want to be 'cooking & cooling with gas', you focus on gas storage rather than electric storage.

I was at the Druridge "wild camp" meeting the other weekend. The weather as far as Solar Energy Harvesting goes was total pants. As it happened I was also parked in some shade for a portion of each day which made it worse. (I didn't realise until I was all setup and couldn't be arsed to move everything).
So from Saturday to Tuesday I was without hookup;
I ran my AC Fridge via the Inverter as normal (i.e. Inverter always on, Fridge kicks on and off as it wants to);
I used an electric blanket for warming the bed as I haven't fitted my Diesel Heater yet;
I used my Induction Hob via 2500W Inverter for boiling water and some simple cooking. (I did use the Safari Chef for cooking as well due to a cookware malfunction! forgot the steel frying pan :ninja: )
I also used my Electric TV and my Firestick, Laptop plugged in to mains - both connecting to the Internet via the Router, Maxxair Roof Fan, LED Lights and 240V LED Rope light for outside in the awning.

And managed to do that all that without resorting to running the engine, using a generator or panicing about killing the batteries. Just before leaving on the Tuesday I was at 60% SOC



Horses for Courses ....

 

[Byronic]

That's a good bit of practical feedback, thanks. Something to mull over
and analyse, and draw conclusions from!

 

[Byronic]

Blimey I must have said something possibly with an air of validity and about it,
Hairydog gave me a like!
There again it just might that both of us are off track!

 

[channa]

Seen these in local adds ,asking £60 ono,no freeze box but im not fussed as i would buy fresh every day,just milk butter bread in fridge.

make great conversions as incubators for my snakey pals ! Would be snapped up here on the mainland

Channa

 

[wildebus]

make great conversions as incubators for my snakey pals ! Would be snapped up here on the mainland

Channa

don't you need warmth for the eggs? or would you fit those reptile electric heat pads? (I fitted a couple of those pads in my Renault Master Workshop to keep the paints from freezing in the wintertime - dead handy )

 

[channa]

don't you need warmth for the eggs? or would you fit those reptile electric heat pads? (I fitted a couple of those pads in my Renault Master Workshop to keep the paints from freezing in the wintertime - dead handy )

yes 90 farenheit and high humidity you can use heat pads or ceramic heat lamps ..
Channa

 

[jimjolli]

Blimey, thank you so much for this thread - very interesting and has made me decide to go a similar route to you with the 500w inverter and that A++ fridge. Can I just ask, how is your inverter wired into your system? I've been planning my system and have decided to go the LiFeYPO4 route and a Voltronic VBCS that covers all the charging needs including MPPT. I have attached my current planned wiring diagram below.
I got comment about it on another forum from a respected member saying that...

'For inverter safety ( and to pass a electrical inspection) where the inverter is powering or possibly powering a non double insulated appliance ( like a fridge) the inverter must be neutral earth bonded and have a RCD in the supply, BUT in this case there must be no external hook up earth connected. ( they cannot be earthed at the same time). I cannot see how this could be easily implemented when you connect to mains.'

How do you make this work? Can you still run your fridge when it's connected to mains?


View attachment 67308

 

[wildebus]

Blimey, thank you so much for this thread - very interesting and has made me decide to go a similar route to you with the 500w inverter and that A++ fridge. Can I just ask, how is your inverter wired into your system? I've been planning my system and have decided to go the LiFeYPO4 route and a Voltronic VBCS that covers all the charging needs including MPPT. I have attached my current planned wiring diagram below.
I got comment about it on another forum from a respected member saying that...

'For inverter safety ( and to pass a electrical inspection) where the inverter is powering or possibly powering a non double insulated appliance ( like a fridge) the inverter must be neutral earth bonded and have a RCD in the supply, BUT in this case there must be no external hook up earth connected. ( they cannot be earthed at the same time). I cannot see how this could be easily implemented when you connect to mains.'

How do you make this work? Can you still run your fridge when it's connected to mains?


View attachment 67308

Ref the comment about "inverter safety" I have Inverter connected to battery (+ve and -ve) plus the inverter earth tag is connected to the chassis (so in reality the same as -ve). The Inverter output goes to a multi-way connector block and the fridge is plugged into that connector block.
I think that is perfectly safe and in fact there is no electrical inspection requirement for Motor Caravans within the UK as far as I am aware. I don't really sign up to what that guy is saying as I read it above TBH.

Do I use the Fridge when the Van is on hookup? Indeed. It never actually runs on hookup directly as I am using a dedicated Inverter outlet regardless of the presence of Hookup or Not.
As it happens, I do have another Inverter I use for High Power devices such as power tools and the Induction hob via another 2 240V Sockets - and the outlet of that Inverter first goes to a 10A Contactor working as an Auto AC Relay with the NC from the Inverter and the NO from the CU. So no Hookup, Inverter is supplying power; On Hookup, Mains is supplying those sockets (via an RCD and DP MCB)

It would be a nice 'thanks' back to me that if you did buy that fridge, you went to the Amazon listing from my link in the thread. makes no difference to the price, but I'll get a few pennies back as it is an Amazon Affliate link.

Ref your Diagram ... looks good to me I can't see anything to worry about ref inverter safety (apart from you don't seem to have fuse protected the wiring to the 500W inverter as it is drawn?)

 

[R0B]

It would be a nice 'thanks' back to me that if you did buy that fridge, you went to the Amazon listing from my link in the thread. makes no difference to the price, but I'll get a few pennies back as it is an Amazon Affliate link.

Sorry wildebus, I DID buy the fridge but I didn't think to do it through your link.
So I'll say thank you here for all your work

 

[jimjolli]

Ref the comment about "inverter safety" I have Inverter connected to battery (+ve and -ve) plus the inverter earth tag is connected to the chassis (so in reality the same as -ve). The Inverter output goes to a multi-way connector block and the fridge is plugged into that connector block.
I think that is perfectly safe and in fact there is no electrical inspection requirement for Motor Caravans within the UK as far as I am aware. I don't really sign up to what that guy is saying as I read it above TBH.

Do I use the Fridge when the Van is on hookup? Indeed. It never actually runs on hookup directly as I am using a dedicated Inverter outlet regardless of the presence of Hookup or Not.
As it happens, I do have another Inverter I use for High Power devices such as power tools and the Induction hob via another 2 240V Sockets - and the outlet of that Inverter first goes to a 10A Contactor working as an Auto AC Relay with the NC from the Inverter and the NO from the CU. So no Hookup, Inverter is supplying power; On Hookup, Mains is supplying those sockets (via an RCD and DP MCB)

It would be a nice 'thanks' back to me that if you did buy that fridge, you went to the Amazon listing from my link in the thread. makes no difference to the price, but I'll get a few pennies back as it is an Amazon Affliate link.

Ref your Diagram ... looks good to me I can't see anything to worry about ref inverter safety (apart from you don't seem to have fuse protected the wiring to the 500W inverter as it is drawn?)

Thanks for your reply. I've amended my wiring diagram slightly to include that fuse for the 500w inverter and also an Auto Relay like yours on my larger inverter.
I think the problem he was getting at was that the fridge shouldn't be earthed to the chassis when a 240v hook up is attached which is also earthed - apparently they shouldn't be earthed at the same time. I've messaged him again to try and find out exactly why.

Of course I'll get the fridge via your link. Can you send it to me again to save me going through 15 pages of comments again. Does the same go for the 500w inverter?

I've attached my new wiring diagram (v.2.2) as well.

Thanks again.

View attachment 67340

 

[wildebus]

Links:
This is the 93L Fridge that I have - Inventor A++ Silver Mini Fridge, Internal Capacity 93L, Silent, Ideal for house, office and dormitories, Max Storage Capability, Energy Savings and Eco-Friendly: Amazon.co.uk: Large Appliances

This is the 43L Fridge that is also an A++ rating - Inventor A++ Compact & Mini Fridge,Silver, 43L Internal Capacity, Ideal for Bedrooms, Office and Dormitories, Energy Savings and Eco-Friendly: Amazon.co.uk: Large Appliances

For completeness, the manufacturer also has an A++ rated Fridge-Freezer - Inventor A++ Silver Under Counter Mini Fridge, Internal Capacity 98L, 4 Star Ice-Box, Silent, Ideal for house, office and dormitories, Max Storage Capability, Energy Savings and Eco-Friendly: Amazon.co.uk: Large Appliances. This however uses about 50% more power due I suspect to the 4* Freezer section. I find the little icebox in the 93L fine for my needs (ice cubes, lollys, etc).

Now all the fridges above are by 'Inventor' who sell exclusively on Amazon, so I don't believe you will find any other legitimate source for these.


Inverters: I will post a couple of links below, including the specific model I bought. I got mine from Amazon as that was the best price I could find at the time I bought, but other places sell Victron kit of course, so you may be able to find better prices possibly?

This is the actual seller and unit I bought - Victron Energy inverter Phoenix connector VE Direct Schuko. 12 - 500 - 230 V: Amazon.co.uk: Lighting
It has the European Schuko socket outlet which I actually preferred as I find them more positive and secure and it was cheaper than any with a UK plug as well.

Finally ... Bluetooth Dongle - Victron Energy VE.Direct Bluetooth Smart Dongle: Amazon.co.uk: DIY & Tools
I used one of these on the Inverter so I could remotely see what the inverter was doing and - if I wanted - turn it off and on. It is not needed to actually use the inverter in anyway, but is a neat little gadget nevertheless


Ref the earthing. I still don't get it. Is he concerned about some kind of Earth Loop?
Something else that people should do but very few do (and I've never witnessed anyone actually do it) is have a ground spike when hooked up.

 

[trevskoda]

So to cut short will it work ok in my van running two 90ah batteries with 200w solar with say some driving every day,if so i may look into fitting one rather than my 202 gas electric.

 

[wildebus]

So to cut short will it work ok in my van running two 90ah batteries with 200w solar with say some driving every day,if so i may look into fitting one rather than my 202 gas electric.

During the summer months the solar will keep up with the Fridge with little difficulty. Over the winter months, if you drive everyday then I would think it would work fine as well. Do you/can you plug into mains overnight?

 

[trevskoda]

During the summer months the solar will keep up with the Fridge with little difficulty. Over the winter months, if you drive everyday then I would think it would work fine as well. Do you/can you plug into mains overnight?

Yes at home.

 

[wildebus]

Just a heads up for anyone looking to do this - the Fridge I used is on a Black Friday deal on Amazon today (19th Nov 2018) and can be had for under £130! - See link here
The Fridge is a great unit in general and if you want a fridge for the home kitchen I'd recommend it anyway.

 

[wildebus]

I have noticed that the link I have for the Fridge is now going to a different Fridge from Inventor
As mentioned previously, availability comes and goes - but the link usually has gone to the same product just the same, so to recap:

To have a similar efficiency to a 12V DC Compressor Fridge such as a Waeco CRX, the starting point for a 240V AC Fridge is one with an A++ Energy Rating
Within that rating range, then look for specific consumption figures. The Fridge I use and would recommend has an Energy Consumption of 84kW/Year, which is very close in value (actually lower as it happens) than the better 12V Compressor Fridges such as the CRX that are specifically designed for Motorhomes and Boats.

 

[Squiffy]

My campervan will have no Gas on-board so a 3-way Fridge is neither an option or something I would want anyway, so Electric-only is my solution.
Due to the high price of DC Compressor Fridges, after some research I decided to install an AC Compresser Fridge.

This post (and some future followups) will show the kind of power usage to expect and if the Electrical setup is sufficient if anyone else is interested in a similar project.
My own setup (400W Solar Array + 440Ah AGM Battery Bank) will be I know,but this analysis may be useful for others interested in a similar option.

INSTALLATION
Fridge: Class A++ 94L Fridge with icebox - £170
(Class A/A+ are available for less, but significantly less efficient. A 12V DC Fridge of comparable size will be around £700)
Inverter: I am using an Inverter. Type is not part of the test and is not relevant.

Below is a video showing power draw into the Inverter (so it includes the energy overhead cost of the inverter as well as the power the Fridge is using). Before Video started, fridge temp dial set to off, Fridge unplugged and Inverter was turned off.

[video=youtube_share;T9JE46VwWxc]

The times below show the event changes during the video - you can see what is causing the power use to go up and down.

Times:
0:05 - Inverter Switched On
0:20 - Fridge Plugged in
0:30 - Fridge Door Opened (so Light comes on)
0:41 - Fridge Temp Dial turned to Max - Compressor In-rush Current comes on
0:45 - In-Rush Current ends
0:53 - Fridge Door Closed (so Light off)

Note that the power use you are seeing from 0:45 is the maximum power draw all the time the fridge is actively cooling, which is a small percentage of the time on a Compressor Fridge (this is what makes them so efficient in use)

After the video ended I changed the temp dial setting to the normal running one

The Power Monitor in the video records both instantaneous power use and also cumulative power over time. I reset it before commencing the test so can check what power has been drawn by Fridge+Inverter over time.
This testing is being carried out in the winter in an unheated Camper. In warmer weather the Fridge would have to work harder and so use more power, but the same is true of any Fridge of course. When Weather permits I will repeat the experiment.


Notes:
The in-rush current occurs on Compressor Fridges, both AC and DC - this high albeit very short current spike is why it is so important to wire up a DC Compressor Fridge with substantial cable (4mm+ depending on length of run) even though the provided specs of a 12V Fridge might imply a much thinner cable is sufficient with a quoted 3-4A current draw.
If the only use of an Inverter is to run an AC Fridge, that extra cost might make this option not as price-attractive, but if your Camper is using the inverter for other purposes so you will have it anyway, there is no additional cost incurred.

Hi wildbus, great post and interesting, just one thing, it would be better if you wish people to follow your thread if the link

[video=youtube_share;T9JE46VwWxc]

Had been live, I would agree with you if your view were "If they are that interested they would retype it into their browser", but I feel in a technical thread its much easer for those not as computer minded to initiate an interest in your thread. This is in no way meant as a criticism more of a suggestion. Phil

 

[wildebus]

Hi wildbus, great post and interesting, just one thing, it would be better if you wish people to follow your thread if the link

[video=youtube_share;T9JE46VwWxc]

Had been live, I would agree with you if your view were "If they are that interested they would retype it into their browser", but I feel in a technical thread its much easer for those not as computer minded to initiate an interest in your thread. This is in no way meant as a criticism more of a suggestion. Phil

What has happened is a lot of the intial posts were ported over from Wildcamping (I think) and that is on a different platform, so some of the BBCodes and Smilies are not the same - hence the links no longer being automatically playable. (and because this site has a timeout on editing old posts, I cannot correct them )

 

[Duckato]

@wildebus
A couple of questions more relevant to this thread than my own re your fridge.

Has it remained acceptably quiet?
How has it behaved on the move, both from an operational and stuff falling over etc. perspective.

I am assuming it is running whist you are driving and being a newbie I have no idea if 12V based compressors are more rugged or have some form of suspension to survive compared to a 240V version etc.

As an aside those power monitors are excellent for the price imho
I bought one with a 100A Shunt to use in my van and I have been suitably impressed with it

Only downside with mine, it does not show reverse current i.e when the batteries are charging which is a pity.

 

[wildebus]

@wildebus
A couple of questions more relevant to this thread than my own re your fridge.

Has it remained acceptably quiet?
How has it behaved on the move, both from an operational and stuff falling over etc. perspective.

I am assuming it is running whist you are driving and being a newbie I have no idea if 12V based compressors are more rugged or have some form of suspension to survive compared to a 240V version etc.

As an aside those power monitors are excellent for the price imho
I bought one with a 100A Shunt to use in my van and I have been suitably impressed with it

Only downside with mine, it does not show reverse current i.e when the batteries are charging which is a pity.

The Fridge is behaving now just as when I first bought it Like another chap who bought one after reading my thread, it was - and still is - the quietest fridge I have owned.
One of the first things I did (not sure if I mentioned or not) was to tape the shelves in position with duct tape so they don't move or rattle. And fitting a lock of some sort is required (I used a child lock). Those two things are standard on an "mobile" fridge and not a domestic one so need to be added.
Running all the time, driving or not, and in temps between below 0C to 50C.

Ref the Meter - you could get a second meter, install that using the same shunt but just reverse the two sense wires and then you will have a meter showing Consumption and a meter showing Charging.
That can actually be much more informative then just a meter with a net total in fact.