Community Forums

Oldme · 03-24-2013, 05:43 PM

I have been trying to learn about inverters, etc.
I read that for modern electronics you need pure sine wave to avoid damage.

I have seen some questions about changing modified sine wave to pure sine wave. I appears it can be done easily.

The link below says "Sinewave UPS System with pure sine wave output and multifunction LCD safeguards mid- to high-end computer systems, servers and networking hardware that use conventional and Active Power Factor Correction (PFC) power supplies".

CyberPower CP1500PFCLCDTAA TAA Compliant UPS 1500VA/900W PFC Compatible Pure Sine Wave: Computers : Walmart.com

Am I correct in my understanding that this could be used to correct a modified sine wave to pure sine for computers, etc?

If so, I would think this could solve problems with older inverters and newer electronics without the major expense of a new inverter.

If starting from scratch, I would just get a pure sine wave to begin with.

FlyingDiver · 03-24-2013, 05:52 PM

I don't think that will work. It's intended to be fed from utility power, which is already "pure". If you feed the MSW inverter output to this unit, you'll get the same MSW out. It's only when there's no power going in and it's running off the internal batteries that it's going to put out PSW.

You would need some sort of line conditioner to "clean up" the MSW, and I don't know of any in the consumer price range that will actually do that.

PyrateSilly · 03-24-2013, 05:57 PM

Here is some reading for you:
Difference Between Pure Sine Wave & Modified Sine Wave Inverter | eHow.com
http://www.xantrex.com/documents/Tec...-Universal.pdf
What is the difference between Modified Sine & Pure Sine Wave Inverters?
Pure Sine Wave Inverter
There is no way to "correct" a modified wave inverter and change it into a pure sine wave inverter. You can take out a mod wave and put in a new pure sine wave inverter. All that is from walmart is a small pure sine wave inverter.

vito.a · 03-24-2013, 06:06 PM

My original Freedom 20 Inverter went out last year. They are no longer in business so I went shopping for a new inverter. I bought a Magnum ME2012-2000 watt inverter. It is not a true sine wave model, but it powers my LED smart TV, blue ray player, and computer just fine. This new inverter is light years ahead of the old one.

"007" · 03-24-2013, 11:08 PM

Thanks for the links Thom I will add your post to the TECH INFO sticky above, good info.

Oldme · 03-25-2013, 04:42 PM

Thanks for all the info.

Now one specific question, if you will.

In looking that at this product, I see the following:
The Xantrex PRO Series Power Inverters

Performance Features:

1000/1800W inverter easily powers TVs, small appliances, and other electronics

Built-in 15A circuit breaker to protect GFCI connected loads

Up to 15A/20A pass through for hardwired loads for XM1000/XM1800 respectively

Digital remote control displays power output, AC source and battery voltage

Detachable remote control can be mounted wherever convenient

Conformal coated electronics provide moisture resistance

Designed to be hard-wired using a terminal strip or by connecting AC through a GFCI receptacle (included)

Protection Features:

Battery over-voltage and under-voltage protection
Over temperature shutdown
Automatic overload protection
Short-circuit protection
Ground fault protection

My question is:

The motor home has 30 amp service.
I see in the Performance Features it says:
"Up to 15A/20A pass through for hardwired loads for XM1000/XM1800 respectively".

Question:
If that inverter was used would this effectively reduce my service to 15A, because that would be the pass through cut off?

In doing an energy audit, for what we want, the 1000 watt unit should be more than enough. We are looking at mainly entertainment and I went to our manufacture's web sites (TV, DVD, laptops) to get wattage usage for each item when I did the audit.

Thanks again for your time and info.
Ken

Ramblin · 03-25-2013, 04:53 PM

Quote:

Originally Posted by FlyingDiver

I don't think that will work. It's intended to be fed from utility power, which is already "pure". If you feed the MSW inverter output to this unit, you'll get the same MSW out. It's only when there's no power going in and it's running off the internal batteries that it's going to put out PSW.

You would need some sort of line conditioner to "clean up" the MSW, and I don't know of any in the consumer price range that will actually do that.

I wonder if you could modify a UPS to always charge from the MSW source and simultaneously power the load from the battery section. Wouldn't that do the same thing?

FlyingDiver · 03-25-2013, 05:21 PM

Quote:

Originally Posted by Ramblin

I wonder if you could modify a UPS to always charge from the MSW source and simultaneously power the load from the battery section. Wouldn't that do the same thing?

You could, but I expect you would burn it out in a short time. UPS systems aren't designed to provide power long term. Inverter systems are. There's also a concern that it's not designed for MSW on the input, and that might cause it to overheat.

FlyingDiver · 03-25-2013, 05:24 PM

Quote:

Originally Posted by Oldme

Question:
If that inverter was used would this effectively reduce my service to 15A, because that would be the pass through cut off?

The service fed from the inverter would be limited to 15A, but you would not run all your AC loads through the inverter. Just the ones you want on the "entertainment" circuit. If your RV was not designed for an inverter originally, that means you need to isolate the one branch circuit when has the entertainment equipment on it, and reroute it to the inverter instead of the main breaker panel. Then you need to run a line from the breaker that WAS feeding that circuit to the input side of the inverter. Plus heavy duty lines from the battery bank to the inverter as well.

Oldme · 03-25-2013, 06:10 PM

Thanks Flying Driver.
I thought so when I read that. I also had a thought, way back in my mind about the inverter just being on certain circuits. You answered that also.

Ref USPS to sine wave...I ran across this:

https://www.youtube.com/watch?v=SBu3AIxkVDQ

I appreciate the knowledge that is freely shared here.

Ken

Pianotuna · 03-25-2013, 09:30 PM

Hi,

You may be better off with a Xantrex prowatt. See bestconverters.com for pricing ($350 for 2000 watts psw)

Pianotuna · 03-26-2013, 06:01 AM

Hi,

And just plug the shore power cord into the inverter, while turning off the converter.

Oldme · 03-28-2013, 01:14 PM

Thanks for the info and ideas.

I think that I am headed towards the Xantrex pro series
1000 or 1800.

Info from the install guide make this seem like it is simple to operate it once installed. No hook - unhook, worry about switching as it is automatic, etc.

Taken form the Install Guide:

"xantrex pro series
1000 & 1800

The XM 1800 is in shore power mode when an AC source (a generator or
utility power) is present to power the appliances connected to the XM
1800. The status LED glows green to indicate that the XM 1800 is using
utility (or generator) power. The inverter draws minimal power from the
battery.

Whether or not the on/off button is on, shore power will pass through the
XM 1800.

When the XM 1800 is on, if the AC source drops to less than 90 Vac or is
disconnected, the transfer switch automatically transfers the appliances to inverter power. The status LED glows yellow to indicate the XM 1800 is using the battery to power the appliances

When the XM 1800 is turned off, the inverter is disabled. Incoming shore
power is passed to the output to power appliances. If the shore power goes away, the appliances do not transfer to inverter power".

http://www.xantrex.com/documents/Pow...artwork%29.pdf

Thanks for the time and shared knowledge.
Ken