Welcome to RVForums.com

  • Register now and join the discussion
  • Friendliest RV Community on the web
  • Modern site for PC's, Phones, Tablets - no 3rd party apps required
  • Ask questions, help others, review campgrounds
  • Get the most out of the RV Lifestyle
  • Invite everyone to RVForums.com and let's have fun
  • Commercial/Vendors welcome

What size inverter?

Welcome to RVForums.com

  • Register now and join the discussion
  • Modern secure site, no 3rd party apps required
  • Invite your friends and let's have fun
  • Commercial/Vendors welcome
  • Friendliest RV community on the web

Rebeccaluke0711

RVF Newbee
Joined
Jul 6, 2021
Messages
1
I recently purchased a 2016 forest river salem 36bhbs. I recently discovered that the fridge will not run off the battery. The fridge will only run when the camper is plugged in. After some research, i discovered that i would need an inverter to allow the batteries power to be switched to 110v so the fridge and any other 110v things in the camper to work. So, my question is...
What size inverter do I need?
Any tips on installation?
 
You need an inverter large enough to handle the starting surge of the compressor. As I recall, for my Samsung residential fridge an 11A surge capability was required. I have a 2800 watt Magnum inverter running my fridge and other 120V outlets while we travel.
 
That's a loaded question. Here are some answers. Starting current (locked rotor) can be as high as 10x running current. Most of the time it's not that high. Replacing the Starting capacitor with a larger one can help reduce the amount of amps needed to start the compressor.

Next is the inverter, if you get a low frequency inverter the momentarily wattage supplied with last about 20 seconds, long enough to start a motor. Where an automotive type inverter that peak power will only last 2 to 6 seconds, and that will not be useful to start a motor.

What that means:

If you select a low frequency inverter you will be safe with one that is sized for 1/2 the Starting current. However if you get an automotive style inverter it should be sized for the full Starting current, roughly twice the capacity when comparing the two.

Because you should buy the low frequency unit. True sine vs. Modified sine should not be a question. However True sine will start the motor easier, and your fridge will last longer.

One more point. The low frequency inverter will use less power at idle than the automotive style unit will.
 
That's a loaded question. Here are some answers. Starting current (locked rotor) can be as high as 10x running current. Most of the time it's not that high. Replacing the Starting capacitor with a larger one can help reduce the amount of amps needed to start the compressor.

Next is the inverter, if you get a low frequency inverter the momentarily wattage supplied with last about 20 seconds, long enough to start a motor. Where an automotive type inverter that peak power will only last 2 to 6 seconds, and that will not be useful to start a motor.

What that means:

If you select a low frequency inverter you will be safe with one that is sized for 1/2 the Starting current. However if you get an automotive style inverter it should be sized for the full Starting current, roughly twice the capacity when comparing the two.

Because you should buy the low frequency unit. True sine vs. Modified sine should not be a question. However True sine will start the motor easier, and your fridge will last longer.

One more point. The low frequency inverter will use less power at idle than the automotive style unit will.
Your info helped me as I am in a similar situation and am just beginning to research inverters. I bought an older but very nice class C and will need one as the fridge needs the gen or shore to work. Thank you for the info. Peace an happy Trails
 
You need an inverter large enough to handle the starting surge of the compressor. As I recall, for my Samsung residential fridge an 11A surge capability was required. I have a 2800 watt Magnum inverter running my fridge and other 120V outlets while we travel.
Thank you for the info Sir. I'm in a similar situation and just beginning to research inverters. I just purchased an older Class C and will need one for my full time RV journey. Peace and Happy Trails
 

Latest posts

Latest resources

Back
Top