Forum Discussion

mlts22's avatar
mlts22
Explorer II
Feb 18, 2014

Small backup PSW inverter, opinions?

As a backup to a main inverter, what would be a decent secondary PSW inverter that would be directly connected to the house batteries? Am looking for some decent brand recommendations. There are plenty of no-name brands, but I'm looking to do this install once, hopefully, so a name brand is important.

Preferably a unit that doesn't have the 120VAC outlets on the inverter itself, but allows them to be wired elsewhere, so the backup inverter can be mounted near the batteries, saving on wire length and thickness. If possible, maybe a remote switch panel so the inverter can be turned off at one spot.

This would be a 500 watt inverter with its own receptacle, normally off, but switched on if there is a need for it (don't want to run the main inverter and its fairly large overhead just to charge a smartphone.)

18 Replies

  • Hi mlts22,

    It would be hard to beat the Morning Star for quality. It is not the cheapest kid on the block though.
  • I stand corrected. I was stating 500 watts as a margin, but at most, I'd not go over 200-250 watts for the planned use of this device. So, 300 watts on this secondary inverter would be plenty. This way, I can let battery charger for a drill do its work overnight without dealing with the overhead that a larger (1500-3000) watt inverter would have.

    I definitely want PSW, so if I choose to run an electric blanket, it would work without frying it.
  • My opinion is that the best PSW inverter for the application you described is the MorningStar SureSine… It is reasonably priced and extremely well built. However this inverter is rated at 300W continuous and 600W for 10 minutes.

    If you need 500W+ continuous Watts, I suggest you take a look at the offerings from Samlex.

    Cheers,
    -Mark
  • We have a Morningstar SureSine 300W inverter. Very efficient will sustain a 600W surge for 10 min, no moving parts. Good customer service!
  • The beauty of 300w is that you can use your existing battery feed and just wire it up behind the 12v/120v panel. No pulling wire all over the RV. Of course you could also jump it off your existing inverter and transfer switch the power into all the same outlets.

    GoPower 150w/300w/600w has lowest idle draw and a remote switch provision.
  • Hi,

    I would either go 300 watts or 1000. 500 is too much for small items and not enough for the toaster etc.
  • I use a 1000w PSW for most things and have a 2000w MSW inverter for the MW, toaster, and kettle. As a back-up if the 1000w quits the 2000 can do it all. If the 2000 quit the 1000 can still run everything plus handle the toaster and kettle, but not the MW. I would have to have a spare, smaller MW like 700w and then the 1000 could do that too. Redundancy is good, but I have not been carrying around the smaller MW as a spare.

    If I had a 500w as back up it would not be a back up for the toaster, kettle, or smaller MW. Got some photos here:

    http://forums.trailerlife.com/Index.cfm/fuseaction/thread/tid/26237237.cfm
  • Smk and I use 300W Go Power PSW inverters. They make different sizes. Any reason you need a 500W?