Power inverters - pure sine vs modified sine

[rmcrist]

Hey folks
Trying to decide between a pure sine wave inverter and a modified some wave inverter. I know pure sine is much better for electronics but can anyone shed some light on this? Looking to just power a mini fridge, recharge laptop, camera and coffee pot.

Thanks!!


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[John61CT]

Recharging should be done off 12V converter not inverter.

Also better IMO to get a proper 12V fridge, but if mains will likely need - or at least be more efficient with - pure sine.

Dunno about the coffee pot, foe me I'd go drip or french press, boil the water with propane.

[Shadow Catcher]

" In general, because the total harmonic distortion is higher in modified square wave inverters, motors will run hotter (less efficiently, consuming up to 30% more energy than with pure sine wave inverters), and likely not last as long." Some appliances don't care other do. As an alternative why not just use 12V.
Inverters are various levels of of efficiency consuming current doing there job. 12V refrigerators are available and adapters for chargers etc. actually are more efficient from 12V.

[mrwall1]

On my teardrop I used a modified.. but I only used it for a couple of items... like a cheap tv.. but since we will have a few more items that run off of 110 in the cargo trailer... I decided to get a pure... just like the guys said... appliances will last longer.... more efficient.... and I got a 1000 watt /2000 peak for $130 bucks of amazon.... not much price difference...

[daveesl77]

I will start this out by first saying a true sine wave inverter is normally the best way to go. HOWEVER, the cost differential between that and a MSW can be substantial and depending on your 120v devices, maybe not necessary to spend the extra $$ on a true sine wave inverter.

For several years we have used an old Haier 3.3 cu ft, 120v dorm fridge I re-acquired from my daughter after college. When traveling, for the past 2 years, we run it from a cheap, Centech MSW 2,000 watt inverter from HF. When driving the fridge runs on the inverter, which is powered by a 12 volt farm battery (Ruralking Exide) and charged from the minivan. When stopped at a place without 120v, we charge the battery with solar panels. I watch both the interior fridge temps, using one of those two location digital, wireless thermometers from WallyWorld and a plug in volt tester. On this last trip of 3,400 miles, 14 days with 8 days driving and 2 days parked without 120v plugin, inside temp on the fridge was maintained at between 31 to 36 F. No problems at all. Days 1, 2, 13, 14 outside temps were between 85 and 95 F and high humidity. We also carry a small 400 watt that we've had for over 10 years, inside the car to use if needed.

So, if you have inexpensive, not real sensitive components, then you may want to consider the MSW over the SW inverter. Like I said, we've been using them for years with no problems, but YMMV.

dave

[dancam]

The fridge and coffee pot are fine on modified wave. With the money you save over a pure sine wave inverter go buy cords for your laptop and camera to plug into the 12v cigerette lighter outlets.
I have a pure sine wave inverter. Its nice, but pricey.

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[m.colley]

Hey folks
Trying to decide between a pure sine wave inverter and a modified some wave inverter. I know pure sine is much better for electronics but can anyone shed some light on this? Looking to just power a mini fridge, recharge laptop, camera and coffee pot.

Thanks!!


Sent from my iPhone using Tapatalk Pro

I actually use both, one PSW large enough to power the mini fridge (while driving or boon docking) and any items that require "clean" AC voltage and a MSW for everything else like tools. The TV, camera, MP3 and DVD/blu ray are usually charge using 12V DC since their all dual voltage.
Buying two inverters actually allowed me to size them closer to my needs without spending major $$$$.


Martin

[MtnDon]

Anything with electronics or a motor will likely have a longer life if powered by a pure sine wave inverter. Motors run hotter, and use more power on a modified sine waveform. Electronics frequently fail prematurely. This is info based on my good friend experience in 20+ years of working with off grid solar powered cabins and large homes.