Samlex SSW-600-12A 600-watt 12V Pure Sine Wave Inverter

The big problem with this unit is that the fan runs at high speed anytime the load is greater than 45 watts, even if the unit is stone cold. The fan is noisy, much louder than an average computer fan. It is annoying in an otherwise quiet room. The fan should be variable speed, with speed determined by the unit's internal temperature.Turned off, the unit pulls 3.3 milliamps. Turned on with no load it pulls 520 ma. The high voltage shutdown is at 14.8 volts. The low voltage alarm, a continuous loud high pitched squeal starts at 10.9 volts. The alarm cannot be disabled, so the unit is useless below that voltage.The efficiency was measured at several power levels by calculating (power out)/(power in). Only resistive loads were used, power factor = 1.0 so efficiency is equal to (volts out times amps out)/(volts in times amps in). The DC voltage was measured directly off the inverter power-in lugs to avoid including external wiring losses. Output parameters were measured with a P4400 watt meter.At 21 watts (118 volts ac x 0.18 amps)/(14.1 volts x 2.17 amps) = 0.69At 57 watts (117 volts ac x 0.49 amps)/(12.6 volts x 5.82 amps) = 0.78At 136 watts (115 volts ac x 1.18 amps)/(11.5 volts x 13.2 amps) = 0.89At 242 watts (115 volts ac x 2.11 amps)/(12.6 volts x 21.8 amps) = 0.88At 544 watts (116 volts ac x 4.69 amps)/(11.8 volts x 54.6 amps) = 0.84At 580 watts (115 volts ac x 5.04 amps)/(11.7 volts x 61.0 amps) = 0.81At 590 watts the unit shuts down, even with plenty of voltage on the input lugs.At the minimum usable voltage the efficiency is;At 545 watts (111 volts ac x 4.91 amps)/(10.9 volts x 65.5 amps) = 0.76Powering a radio, there is some background noise on weak stations. Small power tools with variable speed controllers work well.Bottom line, if they fixed the fan problem it would be a decent unit.

I used to be a loyal fan of Samlex products and years ago they were up there along with Victron, and other hi end gear, but wow, this is like a toy especially when I set it alongside my Renogy PSW, the spaghetti thin wires, flimsy little Alligator clamps, just an overall let down, on the plus side it's very compact and light. Not optimistic about its lifespan.

I took off one star because they send with this unit, cables that are under rated according to their own manual. Also due to the fact that you have to install your own in-line fuse which is not easy to find. Finally found one of appropriate size (60 amps but should be 80 amps according to the manual) at radio shack hanging on a wall with random other items (not fuses). I digress. I hooked this up in my car and am using it to run my Xbox and q180 computer via a lock pick for the screen. None of the cables get too warm which I figure means the supply is enough for the demand without overloading it. Anyway, this little unit has been working great so far. The pure sine wave is the only way to go for sensitive electronics. This one still only comes about 85-89 percent efficiency. Would have preferred one at 95 or so, but for the price, I will see how the electronics hold up to the unusual power provided.

I may have just had a dud because I bought this inverter somewhat based on its other ratings which seemed pretty good. I received it quickly with free shipping which was nice. The cables that come with it are under rated and cheap. It ran good when it worked but after using it for about 5 days it just stopped working. It quit working while I wasn't even using it! I was using my computer one night and had a light on and decided to go to bed and shut off the computer and the light. Woke up the next morning and nothing came on. Looked at the inverter and all the lights were off and it wouldn't put out any power. I tested the batteries and they were fine. I tried disconnecting and reconnecting and it didn't make a difference... I never overloaded it either. Plus the build quality seems sort of flimsy.

The cooling fan runs all the time.Another Samlex at 300W, the fan would be off more than on.Follow Up...after 6 months usage...or about 90 day camp use, this inverter has never hiccuped once.It powers a 32" smart TV, a laptop, a 110v table top fan and various electronic devices, including a Sirius portable radio.I am happy with this purchase despite the constantly running fan.August 2018 update at 1.5 yrs old.While watching a LG 32" LCD smart tv and running a small table top fan, the unit just died.I did not notice a warning light or any beeping.Turned the unit off......waited a few minutes and turned it back on.I heard the sound of something internally electrical make a spitting noise.Shut it off.Never worked again.

The Samlex inverter contained a postit note saying, "This item is defective."In more detail: I paid for a new $180 unit. When it arrived, it had clearly been repackaged, and put in the box backwards carelessly. Stuck to the inverter, and inside the clear plastic case was that postit note. Also, the inverter rattled when shaken.I have never seen such a thing before. This is totally unbelievable, except that it happened. If this review allowed attachments, I'd include a photo.