
After much research, I bought the Wagan EL2201 because I was looking for a pure-sine-wave inverter in this size range and Wagan's other products seem to have a fantastic reputation.
There are lots of poor reviews on this one, and the problem seems to be the same: The unit starts up once, then immediately dies.
Problem: The cigarette lighter adapter comes with a fast-blow fuse. My unit did the same thing, and I found that the fuse (located inside the plug itself) had blown as soon as I plugged a very low-draw radio into the inverter. Inverters have lots of capacitors that need to charge then the unit powers up, creating a momentary large load that a slow-blow fuse can absorb, while a fast-blow cannot.
A 400-Watt inverter is pretty large to run on a cigarette lighter plug in the first place, and should definitely be run directly from the battery or hard-wired if you plan on using anything with a significant draw.
In fact, the instructions say NOT to use the cigarette lighter if you plan on running anything more than 150W.
Solution: Replace the fast-blow fuse included with the inverter with a slow-blow OR a larger fuse (do NOT exceed the rating of your vehicle's outlet!). This is a $0.50 fix and my inverter now works flawlessly!
I'm guessing that the poor reviews are from those who use the lighter adapter and have this problem, while the positives are those who either hard-wire or connect directly to battery.
Now my inverter works great, doesn't play havoc with ANYTHING (unlike my modified sine-wave inverters), and the price was right. The built-in USB is a nice touch too.
Bottom Line: Great inverter for the price if you don't mind replacing a fuse or hard-wiring. As mentioned before, an inverter this size probably should be hard-wired anyway.

I see some very negative reviews of this 400 watt inverter, but my wife and I have been very pleased. We live in a 100% solar home and have found the unit great for running our computer, printer, and powered computer speakers all at the same time. I have even run my Pioneer surround sound, DVD player, and 100watt powered sub-woofer at the same time. This use has been during the day, but there was certainly no shortage of power from the unit whenever the input voltage has been sufficient. One thing I need to mention is that I replaced the cord with the cigar lighter end on it with my own 2 foot long, 10 gauge wire with a three prong plug on it that plugs into our 12vdc in house recepticles. When I first bought the unit I had issues with low voltage signal too, but I do not believe the supplied cigar plug makes good enough contact to conduct the needed voltage. If you have the low voltage issue, try another type of plug or direct wire it. It is not unusual for this unit to be on 6 to 10 hours a day in our home and operates flawlessly. Yes, the cooling fan kicks on and off, but that is what it is supposed to do. I have also used it to charge various battery operated items drills, NiCad chargers, and the like, once again no problems. The ONLY reason I did not give it a five star rating is due to the issue with the cord. When you consider that most cigar lighter sockets are designed to handle 15 amps DC before blowing the on-board fuse (that's with the vehicle running), its easy to see why only the lightest of loads can be run using the supplied plug. Anything large use battery clips, direct wire or hardwire it into your system. Bought the unit about six months ago, should have done the review sooner.
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Hi this is The 5TH inverter i have bought in the last 4 Months. This is also the smallest, and so far best performing. Having said that be honest with yourself when sizing your inverter.I have taken my living room off grid part time. This inverter powers my 40 in. SONY 3D-HDTV-DTV,BOX, MY Surround System 5.1 my Sub woofer,a pole fan.47amp @ 120 volts a/c. 5-5watt 12volt d/c floresent lights for avg 4 hours a night. MY Watt usage avg.about 225-watts,or 1100 watts total@4HR avg. I have Booked about 27 hour so far and videoed my first use of it out of the box .Ran it 7 hours. NO Trouble At All. Puts out allways at least 116.4 volts at all times. this Is Hands Down the best of the Bunch. I,m HOOKED up to 4,100 AMP HR.DEKKA DEEP CYCLE Batterys Im Running 2 # 6 Wires For this Small inverter ,more than enuff for a 3ft run. I live in So.FL. So sun is plentifull,with a 200+watt PV set up.I hope This helps some 1 From making the mistakes I made.
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If you draw more than about 5-10W the fan comes on and it's pretty noisy. Otherwise my unit works fine (I am not using the cigarette lighter plug).
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Summary: If you're looking at this inverter, trust me and buy the Power Bright APS300-12 Pure Sine Power Inverter 300 Watt 12 Volt DC To 110 Volt AC instead! See why below --
Let me preface by saying that I had really high hopes for this inverter. What's not to love? Pure sine, 400 watts, USB port, yes please! My experience however, was far from pleasant. I was excited to test the (first) unit out after it arrived, as the inverter it was replacing, (180 watts) was not large enough to run the equipment I was trying to operate. I wanted to go with a pure sine unit as well because it would be powering electronics like audio gear or a TV. Well, I plugged it in only to find that the red light came on immediately. Bummer. I unplugged and plugged the unit back in and no change. I then decided to just give it a minute and tried the USB port to see if it would charge my phone. That at least worked. Shortly thereafter, the unit started smoking and emitting that ever-so-putrid burning electronics smell. DONE!
I let Amazon know and boxed it up to send back. Exchange was easy as pie and in a few days another (second) unit arrived. Excited to test the replacement out as I thought I may have just gotten a dud, I plugged it in and turned it on. No red light! Super! I then began to do some testing. I plugged in my laptop to the inverter and my touchpad immediately stopped working. Weird. So I did some more testing. I plugged in an audio amp and it worked but was very noisy on both the output and the sound the transformer was making on the amp itself. I plugged in a strand of LED Christmas lights and not all the lights would work. I plugged in my laptop again and noticed it would not charge. It would momentarily then stop then charge again and repeat. The transformer in the power supply was also making an abnormal buzzing sound. Through the course of more testing, I found that anything I plugged into the inverter that had a capacitive touch interface would stop working as soon as plugged it into the inverter (smartphone, touchpad, etc). I also found that the unit put out a large amounts of RF interference (AM radio distorted when inverter was on). Super weird. The fan was also running almost constantly even with a low load on the unit.
The RF issue has been commented on by others that have bought the Aims 180 pure sine inverter (which is as far as I can tell identical to the Wagan 180 watt pure sine version). So has the issue of blowing up, smoking, etc. Before I start to ramble, these units over promise and under deliver. I returned the second unit to Amazon after being so dissatisfied.
I ended up purchasing the Power Bright APS300-12 Pure Sine Power Inverter 300 Watt 12 Volt DC To 110 Volt AC. I could not be more satisfied with that unit. Way better built than the Wagan. Works as advertised. I was sold within minutes and will not hesitate to buy another Power Bright inverter.
I hope reading this saves you all the trouble I went through!