Good Deal on PSW Inverter

[Kmmech]

Hello all. Ive been searching for a new inverter to replace the old modified sine wave. Came across a deal at Lowes. They have Zamp pure sine inverters for 60% off through Jan 23. I just ordered the 1000 watt with free shipping for $131. Just thought Id pass it on for those interested.

 

[RVTravel]

May be this one.

http://www.zampsolar.com/product/zamp-solar-1000-watt-pure-sine-wave-inverter-zp-1000ps/

 

[RVTravel]

https://www.amazon.com/Zamp-solar-ZP1000PS-Solar-Inverter/dp/B00O5BU2SK

One issue, if correct model, is no reverse polarity protection. Fuses on inside of unit. Not sure what that means for attempting to change them out.

 

[blars]

It looks like the 2000 watt version is out of stock. $216 price.

 

[jimindenver]

That's one heck of a price on those. Too bad I can't pick one up at the Lowes just south of here.

 

[SternWake]

It would be great is there was a standard that PSW inverters had to meet to be labelled as PSW or true sine wave.

I'd love to see the actual sine wave at 90% of max load and the voltage and HZ of My Wagan Elite 400 PSW, and my 800 watt 10+ year old MSW Coleman.  Neither ever get much use.

In my opinion, The actual sine wave at high load should be shown in product literature, mandatory.

I suspect many budget PSW inverters would not sell very well if it were.

How many steps are allowed for an inverter to be called PSW?

I'd hope for at least than many.  

I have no idea what requirements, if any, an inverter  manufacturer must meet to market their products with extra special flashy wording and fonts, and balance that against the price of competitive products and possible lawsuits if taken to court over outright false claims.

As Always, buyer beware, and shopping by price alone, might find a consumer questioning value.

How many times have you seen on a forum, where a member has found the cheapest possible product online, then starting a thread asking, basically hoping for somebody to basically praise the product/seller, and the price and this the wise frugality of the initial poster?

Usually any non negative results use the words 'works just fine'

Works great
Works OK
Works poorly
Works just fine
Does not work.

Beware of 'just fine'  

The day before battery X shorted a Cell, it worked 'just fine'.

 

[akrvbob]

I went to the site and looked for the no-load draw, I couldn't find it. To me, that's a big red-flag, every inverter should tell you the no-load draw. Especially pure-sine since there's is higher because they work harder.

If it's .5 amp, that's very good, if it's 2.5 amps, that's very bad. But we don;t know.

 

[bonvanroulez]

I purchased one of the 1000 watt Zamp inverters from Lowes on this sale; I returned it for a refund.

I had been thinking about a backup, or possible replacement, for my 5 year old 1500 watt psw inverter. My inverter loads are a compressor fridge, 19 inch led television, and laptop charging. One of the specs missing from all literature was the standby draw, important to me because powering a fridge my inverter is on 24/7, 365 days. I called Zamp customer service in Bend, OR and a very helpful tech told me he thought the standby draw would be .5 amp. My present inverters standby draw is .35 amp. I thought it close enough to buy one and try it out.

After unpacking and initial setup I actually measured a standby draw of only .2 amp which I thought quite good so I finished hooking it up and plugged in the fridge. The inverter easily started the fridge. After a full day and night of running, I checked my morning battery voltage and found it noticeably lower than I would normally see. The inverter felt warm and testing with an IR thermometer showed it was at least 20 degrees warmer than ambient. My old inverter idles barely above ambient temp. After unplugging the fridge I again checked standby draw and found it now at 1.2 amps. At that draw the inverter alone, with no loads, would be drawing 29 amp/hours a day. I let it run for another 24 hours and got similar results.

Whether it was the nature of the product or if it was a defective unit, I decided to return it and was refunded with no questions.

A few other things about the inverter; the literature described a soft start mode with heavy loads, when the refrigerator started the line voltage dropped such that the TV would shut off. Also, I did not care for the momentary push-button power switch. I’ve been thinking about dedicating an inverter to the fridge, wiring the fridge’s temp controller to cycle the inverter. That would have required some circuit hacking to accomplish given the Zamp inverter’s power circuit.

If someone needed a cheap psw inverter for occasional use this could be a good deal; for my application I couldn’t live with its performance.

 

[SternWake]

Good report. Next time I want oscilliscope print outs at various loads!



I had forgotten about the standby draws. I once measured my coleman 800 MSW at 0.68 amps but more recently measured it at 0.24.

My 400 watt Wagan elite PSW drws 0.26 amps every time I tested standby draw.



0.68 amp continuous, is more than my 12v compressor draws over that same hour 90% of the time. Lately with cool temps, it has been averaging 0.54Ah consumption per hour to maintain 34.5f average interior temps.

 

[RVTravel]

What device do you use to test standby draw?

 

[SternWake]

Easiest is a Clamp on DC Ammeter.

Not sure if using a digital multimeter inline on a power lead is wise. Usually when hooking an inverter to a battery even if inverter is off, a spark jumps. Could blow the fuse in the multimeter set to amps run inline on a circuit.