inverter question

[SunEagle]

So the problem is the fridge running 24hrs at 150 watt burning 3600wh.
It wont be running all the time so I need to figure out how much power it takes over 24 hrs.

Mark

There is a device called "kill a watt" meter that will measure the amount of watts an appliance uses. You would measure the load for a few days which would get you an average daily watt hour usage.

More than likely, unless the fridge is very inefficient, it probably draws that 150watts for a few minutes every hour. But if you guess too little you can easily undersize your battery system and quickly kill them.

[mark2310]

There is a device called "kill a watt" meter that will measure the amount of watts an appliance uses. You would measure the load for a few days which would get you an average daily watt hour usage.

More than likely, unless the fridge is very inefficient, it probably draws that 150watts for a few minutes every hour. But if you guess too little you can easily undersize your battery system and quickly kill them.

Thanks
Ive got one of those only problem is the fridge is in the van and the van is in the middle of nowhere so will have to run the generator for a while to figure out what its using.
Anyone got any idea a 12v 150 watt fridge will use in 24hrs?

Mark

[SunEagle]

Thanks
Ive got one of those only problem is the fridge is in the van and the van is in the middle of nowhere so will have to run the generator for a while to figure out what its using.
Anyone got any idea a 12v 150 watt fridge will use in 24hrs?

Mark

Some refrigerators have a yearly estimated watt hour usage printed on their labels.

I don't know if that 12volt unit has that information but my guess there is not a lot of insulation on that thing so it could need to run a lot to keep the temps low inside.

[Bucho]

So the problem is the fridge running 24hrs at 150 watt burning 3600wh.
It wont be running all the time so I need to figure out how much power it takes over 24 hrs.

Mark

Yeah there's no way your fridge is using that much, more likely something like a third of that. You can probably find a number online or in its literature but the way they're tested can be kind of rigged so to get a real number kind of takes a killowatt.

Also, if you plug in a room temperature fridge and measure that it will show you a significantly higher power consumption than normal.

[mark2310]

Yeah there's no way your fridge is using that much, more likely something like a third of that. You can probably find a number online or in its literature but the way they're tested can be kind of rigged so to get a real number kind of takes a killowatt.

Also, if you plug in a room temperature fridge and measure that it will show you a significantly higher power consumption than normal.

Hi
Thanks again for all of the info.
I think I will use a battery bank of 4 12v 125ah wired as shown in the earlier link.

As I have mentioned im not always there in the van so this will give recovery time to the system should it be run to low, but as with most things im tight so will probably turn the fridge off last thing at night.

We also have a lot of sun/daylight there about 6-7hrs winter and about 16hrs this time of year.
Hope to start testing and building in the next couple of weeks.

Thanks again for all of your help.

Mark

[mark2310]

Hi
Thanks again for all of the info.
I think I will use a battery bank of 4 12v 125ah wired as shown in the earlier link.

As I have mentioned im not always there in the van so this will give recovery time to the system should it be run to low, but as with most things im tight so will probably turn the fridge off last thing at night.

We also have a lot of sun/daylight there about 6-7hrs winter and about 16hrs this time of year.
Hope to start testing and building in the next couple of weeks.

Thanks again for all of your help.

Mark

Opps

Another quick question.
Should I keep the battery box separate from the controllers?
I guess the answer will be yes and well ventilated.

Mark

[Mike90250]

Opps

Another quick question.
Should I keep the battery box separate from the controllers?
I guess the answer will be yes and well ventilated.

Mark

yes, you don't want acid mist from batteries getting into the electronics.