Yep,, Fridges Again ??

[Ridge Runner]

I just done some testing on mine because I read that many people say the Temp Gauge is 5 degrees out so I plugged mine in and I set it to 4*c and it took 11 minutes to get to it from room temp,

Then it took 2 hours 26 minutes 52 seconds for it to switch it's self back on, So I turned it off and then spent 5 minutes taking temp readings with a Laser when the dial was saying 5*c and the Average temp works out to be bang on 5*c when you compare the Dairy shelf to the coldest part of the fridge,

So I checked out the fridge freezer in my kitchen and the same principal applies to them too,

When you read these reports or reviews just remember that such people are just taking the reading in one spot and you have to divide the over all Temp to find out the accuracy of them,

john

 

[Nightjar]

My 1975 39/40L Engel .....
Is over at Engel World getting a tune up ...
Cheers Nanjim
Jim

If you want any technical details about an Engel Fridge contact the above business situated in Midland.
Ask for Uncle Graham (he's not my Uncle) what he doesn't know about Engels isn't worth knowing.
If you do contact Graham ask him to explain about the common cause of portable fridge failure running them on 240V from a generator.
(Hint: What does a generator do when running out of fuel?)

http://www.engelworld.com.au/en/content/4-about-us

 

[condor22]

My 1975 39/40L Engel .....
Is over at Engel World getting a tune up ...
Cheers Nanjim
Jim

If you want any technical details about an Engel Fridge contact the above business situated in Midland.
Ask for Uncle Graham (he's not my Uncle) what he doesn't know about Engels isn't worth knowing.
If you do contact Graham ask him to explain about the common cause of portable fridge failure running them on 240V from a generator.
(Hint: What does a generator do when running out of fuel?)

http://www.engelworld.com.au/en/content/4-about-us

Agreed, most 12 volt devices, i.e. Fridge, TV, Stereo, should be run from a Deep Cycle battery. A Generator should then be used to charge the battery using a separate 240VAC charger, preferably a smart charger. If there is a "spike" from the genny a good quality charger will absorb the spike or at the most blow its fuse.

In simple terms, the charger outputs electronically regulated DC volts and amps, which the battery absorbs, eliminating any "bad" power going to your device.

The 12 volt output of a genny (including Honda and Yamaha) is exactly that a 12 volt power supply, it will not "properly" charge a 12 volt battery.

 

[Ridge Runner]

My 1975 39/40L Engel .....
Is over at Engel World getting a tune up ...
Cheers Nanjim
Jim

If you want any technical details about an Engel Fridge contact the above business situated in Midland.
Ask for Uncle Graham (he's not my Uncle) what he doesn't know about Engels isn't worth knowing.
If you do contact Graham ask him to explain about the common cause of portable fridge failure running them on 240V from a generator.
(Hint: What does a generator do when running out of fuel?)

http://www.engelworld.com.au/en/content/4-about-us

Agreed, most 12 volt devices, i.e. Fridge, TV, Stereo, should be run from a Deep Cycle battery. A Generator should then be used to charge the battery using a separate 240VAC charger, preferably a smart charger. If there is a "spike" from the genny a good quality charger will absorb the spike or at the most blow its fuse.

In simple terms, the charger outputs electronically regulated DC volts and amps, which the battery absorbs, eliminating any "bad" power going to your device.

The 12 volt output of a genny (including Honda and Yamaha) is exactly that a 12 volt power supply, it will not "properly" charge a 12 volt battery.

The genny's with a 12v supply is normally for charging battery's so it will be higher than 13.8 and they say that the genny should be a sine wave model,

 

[condor22]

A little off topic but - My 1st van had a Vitrifigo 12 volt compressor fridge. When I was having it built and designing the electrics, I was asked if I wanted a "step mode" 240VAC power supply installed. To explain, this is a 240V power supply that Auto senses 240V i.e. when off mains supply the fridge works on 12VDC from the 2 x 100AH batteries I had in the van. When the van is plugged into mains power the "step mode" senses this and automatically switches the fridge to the 240V supply and disconnects the fridge from the house batteries. This fridge although vertical door, works the same way as a portable Engel, Waeco etc.

I chose not to do this, because I had also installed an Inverter that was hard wired to provide power to the 240 van outlet sockets via a manually operated switch using the same circuit breakers as mains. This meant that a step mode would sense this, switch to 240 which was now being supplied by inverter. It is ridiculous to have a 12V fridge working on 240 which is inverted from battery. In the same context a generator inverts 12VDC to produce 240VAC

My logic being, if the fridge is connected to the batteries on 12VDC and off Mains power, I could charge the batteries using my genny and the installed smart charger. When on Mains power the smart charger is still charging the batteries, so there is no need to connect the fridge to 240VAC anyway. I also had solar input, but not enough to replace all of the DC used, but enough that I only needed to run the genny every 2-3 days.

Apart from this, my primary reason for not running the Vitrifigo on 240VAC was to avoid direct generator input, I only ever use it to charge the battery or run my Microwave, but ensure it's fuelled up first.

The other point re generators; If you run one, know your equipment, when you feel that it is getting close to a refuel, turn off your devices, disconnect the genny, switch it off, carefully refuel, switch the genny back on, reconnect and then switch your devices back on, rather than letting it splutter to a stop. It's better for the genny and might save you having to replace expensive devices.........

 

[Ridge Runner]

So are you saying you should not run them from a genny or and Inverter ??

john

 

[Dingo]

I just bought one of these and it runs so sweet better than the Waeco (60 litre) I owned before time will tell of cause.

New Digital Platinum Series.New User friendly digital controls with built in battery monitor. This is a portable fridge-freezer with the convenience of separate fridge (32 litre) and freezer (25 litre) compartments. The thermostatically controlled fan provides cool air from the freezer section to maintain accurate refrigerator temperature. Once again Steel cabinet, Steel lid and Steel handles that can be used as tie down points. Supplied with both 12 volt and 240 volt cords with auto switching as standard.

#1

 

[Nightjar]

Condor you have nailed it. Always put a battery between the fridge and a generator when you are away from the grid.
In the service room of the Engel World Midland are many dead components, usually capacitors.
Mostly failed because the fridges had been plugged into generators and left to run out of fuel. As Condor has explained the generators spike when fuel is depleted.

 

[Ridge Runner]

Condor you have nailed it. Always put a battery between the fridge and a generator when you are away from the grid.
In the service room of the Engel World Midland are many dead components, usually capacitors.
Mostly failed because the fridges had been plugged into generators and left to run out of fuel. As Condor has explained the generators spike when fuel is depleted.

Yeah that's coz they Rev up as they are about to cut out, I think when I put my camper together I am going to run 2 banks of 2 Batteries so when one lot is charging the other is working and then I won't have to worry about Voltage spikes,

john

 

[Nightjar]

John (Gold Nuggets),
Apologies for digressing away from the original post but fridges, batteries and generators are part and parcel of camping away from the grid. (And we haven't brought solar into the equation)
You don't have to go that added expense + excessive weight.
Read Condor's report again, he mentions charging batteries if required with a 240/12V smart charger. If you allow the generator to run out of fuel the spike will not effect your fridge running from the 12V battery you are charging.
Another explanation here;

http://www.fridge-and-solar.net/gen_charge.htm

 

[Ridge Runner]

John (Gold Nuggets),
Apologies for digressing away from the original post but fridges, batteries and generators are part and parcel of camping away from the grid. (And we haven't brought solar into the equation)
You don't have to go that added expense + excessive weight.
Read Condor's report again, he mentions charging batteries if required with a 240/12V smart charger. If you allow the generator to run out of fuel the spike will not effect your fridge running from the 12V battery you are charging.
Another explanation here;

http://www.fridge-and-solar.net/gen_charge.htm

No Apologies needed mate, because buying a fridge is just the first stage and people need to be Educated before they plug it in and that would be best served within the one topic because while it is still fresh in every ones mind, Including mine.

Running the fridge off a genny's 240 volt outlet would spike the fridge but don't 240 gadgets have something like a 10% +/- leeway built in to them ?
I am glad you Guys threw this issue in to the mix because I would have gone Balistic if I had made such a mistake because I have been putting of buying a proper fridge/freezer making do with them electronic coolers etc and the proper fridge I did have got stolen recently as you know.

john

 

[Nightjar]

John,
Have modified this "Box of Tricks" over the years and this years mods should be last thanks to some kindly advice from a good friend.
The box is bolted onto the back of my ute and connected to a battery under the tray before each season. (Charged while traveling by vehicle alternator)
(1) 240V/12V 40amp charger is hard wired to battery, when needed the charger is plugged into the generator.
(2) 600W Inverter (Very rarely ever used) There are 240V detector & radio chargers if the 12V fail.
(3) PWM regulator connected to solar panel fixed to roof of ute.
(4) MPPT regulator connected to two 60W panels in series. (These are portable and plugged in via red Anderson plug in pic)
(5) The 80L & 39L Engels on back of ute plugged into the two vacant sockets in pic.
(6) Other 12V outlets connect chargers for Detectors, radios, lighting, usb phone charger etc etc etc.
(7) A hard wired 12V water pump is connected to two 60L water tanks under tray.
(8) The caravan has its own separate system charged by two panels and a smart charger when the generator is running.
(9) The caravan 12V utilities, water pump, TV + Humax & led lighting. Fridge is 12V while travelling, gas when stationary. Yet to be put to the test is an extra 12V pressure pump connected to a recyclable shower set up using the existing shower recess. (Heat up 10L bucket of water over the campfire, tip it into the shower base, flip the switch then you can shower until the water goes cold.) Two very happy campers.

 

[condor22]

So are you saying you should not run them from a genny or and Inverter ??

john

John, in short Yes and No, lol. Follow the KISS principle.

Why convert 12VDC to 240VAC using an inverter to run a 12VDC fridge.

If you connect a 12V fridge via the 240VAC power lead to an inverter, which is then connected to a battery. Ultimately you are still running it from the battery,
except there is an efficiency loss using an inverter. Using Ohms Law, my old 300W pure sine wave inverter would pull 300W divide by 12V = 25amps.
It actually pulled 27+ amps when I loaded it up to about 290W (if I tried 300W it tripped the overload). So for the same wattage output an inverter pulls
about 10% more battery power than direct DC connection.

This applies to the whole range of 12VDC fridges; The Engel MT17F (15lt) is rated at 2.5A max at 12VDC = 30W. It's rated at 33W when on 240VAC,
because of internal efficiency losses within the fridge.

Can you run a fridge direct from a Genny - Yes - Providing the Genny is Automatic Voltage Regulated (A.V.R.) Current Honda EU1000 & EU2000, Yamaha
equiv and even Engel's own gennys are A.V.R. However, I would be very careful with the el cheapo gennys.

So to answer your question; Can you run a 12V fridge from a genny and or an inverter - Yes, but if you have a battery in your system, why would you want to.

 

[condor22]

Forgot to mention, the Honda and Yamaha gennys have an eco demand throttle, they will increase and decrease revs as demand increases and decreases.

I.E. connect an Engel using 30W, the genny is not much more than idle speed, switch the microwave on and it can now be using over 1000W (including the Engel) and its revving a hell of a lot more because of demand. This should not hurt a quality fridge when using a quality genny.

Would I do this? NO

Why? I said "should not" it's not absolute and too expensive to risk.

 

[Ridge Runner]

John,
Have modified this "Box of Tricks" over the years and this years mods should be last thanks to some kindly advice from a good friend.
The box is bolted onto the back of my ute and connected to a battery under the tray before each season. (Charged while traveling by vehicle alternator)
(1) 240V/12V 40amp charger is hard wired to battery, when needed the charger is plugged into the generator.
(2) 600W Inverter (Very rarely ever used) There are 240V detector & radio chargers if the 12V fail.
(3) PWM regulator connected to solar panel fixed to roof of ute.
(4) MPPT regulator connected to two 60W panels in series. (These are portable and plugged in via red Anderson plug in pic)
(5) The 80L & 39L Engels on back of ute plugged into the two vacant sockets in pic.
(6) Other 12V outlets connect chargers for Detectors, radios, lighting, usb phone charger etc etc etc.
(7) A hard wired 12V water pump is connected to two 60L water tanks under tray.
(8) The caravan has its own separate system charged by two panels and a smart charger when the generator is running.
(9) The caravan 12V utilities, water pump, TV + Humax & led lighting. Fridge is 12V while travelling, gas when stationary. Yet to be put to the test is an extra 12V pressure pump connected to a recyclable shower set up using the existing shower recess. (Heat up 10L bucket of water over the campfire, tip it into the shower base, flip the switch then you can shower until the water goes cold.) Two very happy campers.

http://i151.photobucket.com/albums/s122/nightjar3/Box%20of%20tricks.jpg

That's very impressive, you have it well set, Is your Inverter Pure sine wave or is it the normal type, because the 3 I have are the normal type,
I have a monster 35 amp charger but it is on wheel built for starting Trucks and Buses, it puts out 310 Amps on Boost so I think that I need to down size for the camper I have seen a 40 amp model which is the size of a loaf of bread that might be better suited.

john

 

[Ridge Runner]

So are you saying you should not run them from a genny or and Inverter ??

john

John, in short Yes and No, lol. Follow the KISS principle.

Why convert 12VDC to 240VAC using an inverter to run a 12VDC fridge.

If you connect a 12V fridge via the 240VAC power lead to an inverter, which is then connected to a battery. Ultimately you are still running it from the battery,
except there is an efficiency loss using an inverter. Using Ohms Law, my old 300W pure sine wave inverter would pull 300W divide by 12V = 25amps.
It actually pulled 27+ amps when I loaded it up to about 290W (if I tried 300W it tripped the overload). So for the same wattage output an inverter pulls
about 10% more battery power than direct DC connection.

This applies to the whole range of 12VDC fridges; The Engel MT17F (15lt) is rated at 2.5A max at 12VDC = 30W. It's rated at 33W when on 240VAC,
because of internal efficiency losses within the fridge.

Can you run a fridge direct from a Genny - Yes - Providing the Genny is Automatic Voltage Regulated (A.V.R.) Current Honda EU1000 & EU2000, Yamaha
equiv and even Engel's own gennys are A.V.R. However, I would be very careful with the el cheapo gennys.

So to answer your question; Can you run a 12V fridge from a genny and or an inverter - Yes, but if you have a battery in your system, why would you want to.

Ok so I need to add an AVR Genny, but still run off the primary 12 volt supply from the battery then all is safe, The Genny is alright for powering the camper but keep the fridge hooked up to it's own 12 volt supply,

Thanks for that

 

[condor22]

John, I don't want to take this thread away from Fridges so all I'll say is have a look at the thread I did on;

https://www.prospectingaustralia.com/forum/viewtopic.php?id=9156 (read a bit at a time, there's a fair bit to digest)

To answer your last;

You have a camper with a 12VDC battery system.

• Run the fridge off 12VDC[/*]
• Charge the battery from a genny via a smart charger or with solar as needed.[/*]

 

[Ridge Runner]

Forgot to mention, the Honda and Yamaha gennys have an eco demand throttle, they will increase and decrease revs as demand increases and decreases.

I.E. connect an Engel using 30W, the genny is not much more than idle speed, switch the microwave on and it can now be using over 1000W (including the Engel) and its revving a hell of a lot more because of demand. This should not hurt a quality fridge when using a quality genny.

Would I do this? NO

Why? I said "should not" it's not absolute and too expensive to risk.

Would this one be safe enough or not, they say it is pure sign wave but what about the rest of it ??

john

 

[Ridge Runner]

Well I kept testing my fridge til the early hours and when I set it to 2*c (Aussie GOV food people say 1.6*c) it ran for about 12 minutes to get it at the right temp and it did not start up again until 2 hours 10 minutes later so basing it on those figures it is going to start 11.080 times in 24 hours or it will run for 2 hours 13 minutes in any 24 hour period. But don't forget the room temps is about 20*c ish.

 

[Nightjar]

Depends how loaded your fridge is?
An economical way to run your fridge is to top it up with your food/drink supply, chill/freeze it down from your home grid supply then head for the hills, in our case the flat ground.
Obviously an empty fridge does not have anything solid to retain a desired low temperature so it will cycle more frequently putting extra draw on your battery. Always leave some air space around the contents.
I see you are doing timed tests, try running it empty and then with it filled to record your cycle times.

****Don't run your fridge on 240V from your generator even if it is a Pure Sine Inverter.****