Pure Sign Wave Inverter

[Darwin Maring]

Source for a Pure Sign Wave Inverter

Terex Telelect Pure Sine Inverter Tel 12 1500N | eBay

[Thomas G.]

Pure sign inverters are not hard to find. What is special about this one?

[Terry G]

Whoa, they won't tell you the real price and they want $36 for standard shipping! It would have to be awfully special for me to consider that. Does it do anything clever--card tricks, walk the dog, make coffee for you in the morning?

And it's sine wave. A sign wave is what you get from those people standing out by the street in funny costumes.

[Byron Kinnaman]

Originally Posted by Terry G

Whoa, they won't tell you the real price and they want $36 for standard shipping! It would have to be awfully special for me to consider that. Does it do anything clever--card tricks, walk the dog, make coffee for you in the morning?

And it's sine wave. A sign wave is what you get from those people standing out by the street in funny costumes.

Sine wave or sign wave??

[honda03842]

Nothing against those who want a sine waye Inverter, however I have yet to see a peice of equipment in my trailer that is not happy running on non-sine wave Inverters, this includes numerous tvs, computers, ..... My 1200 watt non sine wave inverter was about the same as the shipping cost for the sine wave inverter. We paid $59 at the Black and Decker outlet.

[Per Walthinsen]

I didn't find any equipment unhappy with our non-sine wave inverter either, until my wife tried to run her little sewing machine on it. It sputtered and quit and acted sew contrary.

A 400w (Samlex brand) sine wave inverter was hardwired in several years ago and the needle has been flying ever since.

My understanding is that some laptops are unhappy too, and likely anything using an electric motor will balk or heat up unnaturally.

[Byron Kinnaman]

Originally Posted by honda03842

Nothing against those who want a sine waye Inverter, however I have yet to see a peice of equipment in my trailer that is not happy running on non-sine wave Inverters, this includes numerous tvs, computers, ..... My 1200 watt non sine wave inverter was about the same as the shipping cost for the sine wave inverter. We paid $59 at the Black and Decker outlet.

We have 2 computers that don't like non-sine wave inverters. I had a 100 watt and a 400 watt, replace them with a 300 watt pure sine wave. I don't use that very often now since I got 12 Volt chargers for almost everything.

[rabbit]

Square wave is for squares. Why not produce AC that makes a pretty picture on a scope? Nuu-ooh, that's not the reason. This is a case where what's right for Byron is right for everybody unless you like cooking laptops.

jack

[honda03842]

I don't understand Jack's reply. Both Byron and I were relating our experiences. In my case over 3 brands of computers.

If your products require the more expensive sine wave than that's your solution.

[Brian B-P]

I have a non-sine wave 300 watt inverter that has run laptop supplies, battery chargers, and a heating pad without problems. As the variety of responses shows, experience varies and there is no guarantee how any specific bit of equipment will react to non-sine-wave power.

[Spanke]

Your laptop, for the most part, really doesn't care what type of AC it's getting!

check this out: Is square wave inverter harmful to electronic devices

Let the Can O' Worms be opened!

I'm done.

Spanke

[Brian B-P]

Originally Posted by Spanke

Your laptop, for the most part, really doesn't care what type of AC it's getting!

It makes sense to me that switching power supplies (which are now nearly universal) would care little about waveform, so I would not expect laptop supply bricks, modern battery chargers, chargers for phones and similar gadgets, etc. to have any problem with non-sine-wave inverters.

On the other hand, this hasn't worked for some people, and I'm not questioning the validity of their observations.

Originally Posted by Spanke

check this out: Is square wave inverter harmful to electronic devices

Okay, now I've read the linked article. I had low expectations of anything from wiki.answers.com, but this one looks good.

[jwcolby54]

The amount of power delivered varies between the types. Over the years i have seen square wave, modified sine wave, triangle wave an sine wave inverters. One issue can be very strong harmonics fed into the equipment using the voltage. A square wave will actually break down into the base frequency plus 3f plus 5f etc. Those harmonics may or may not cause issues, depending on how well the power supply can filter them out (for electronics).

In any event the equipment almost always EXPECTS a sine wave because that is what most of the world delivers. If it works on non sine then you win. Worst case it can burn it up.

I tried to run my cpap with heater on a cheap inverter. The heater died, the cpap itself worked just fine. Go figure.

[floyd]

I decided on a true sine wave inverter after trying three different modified sine inverters which all produced so much RF interference as to render them useless. As I recall, "Peak" was one of the useless ones.

[Byron Kinnaman]

As I stated earlier I had a 100 Watt and a 400 Watt non-sine wave inverter. Those both ran my laptop just fine at the time. I changed computers and added one for my wife. Both of those computers wouldn't work with either the 100 Watt or 400 Watt inverters. Nothing happened with 100 Watt, they just wouldn't run or charge the battery. The 400 Watt the circuit breaker kept tripping.
I changed to a pure sin-wave and both work as they're supposed too.

As was mentioned about harmonics, I suspected at the time the shape of the 60hz frequency was less important than the harmonics. I think the harmonics and the design of the computer power supply caused the problems.

Be careful what you read and believe on the internet, it might be exactly true.

[Briantb]

Stick with sine wave inventor.. Cheap insurance for whatever you have on your computer and haven't yet backed up properly... Why take a chance.. Tv can be replaced not pictures and movies always

[Ed Harris]

For what its worth,modern inverters really are just switching power supplies.
Their input is just 12vdc and output is 120vac.

Many computers that need AC current to run just use switching supplies to do the same thing as the inverter really and many also can be used with dedicated switching supplies/inverters to let them run on a 12vdc input.
These are the supplies I try to find,designed to optimize my sensitive device for 12vdc use.

As with most electronics the more you spend the better quality device you might expect to get.
Going from nasty unfiltered,choppy square waves to pure,clean true sine waves are just the extra features that you pay for.

Some inverters work fine with many devices and other devices seem to require more heavily filtered and pure AC power to work correctly.

Buy what you need or buy more than you need to be safe.