Pure sine wave inverter

Topic: Pure sine wave inverter (Read 1355 times) previous topic - next topic

Pure sine wave inverter

May 21, 2019, 06:01:43 pm

Just ordered a new residential fridge and was wondering what size/type pure sine wave inverter is best/needed.

Larry

Re: Pure sine wave inverter

Reply #1 – May 21, 2019, 06:06:05 pm

Larry,

What is the "start up" amps? Use that plus 25% as a reasonable objective.

Re: Pure sine wave inverter

Reply #2 – May 21, 2019, 07:06:10 pm

Versus replace the main inverter?

The idea that a small inverter saves energy is difficult to quantify.

The possible differences in efficiency for a specific load are tiny.

Almost all major inverters run 90% efficiency.

So a 750 watt load loses 75 watts.

A 92% effeciency unit loses 60 watts.

The separate battery cabling necessary to hook up a inverter consumes electricity itself.

No free lunch.

The idle voltage differences are measurable but very small.

I know that power consumption per foot of wiring are published.

Wiring in a small inverter using even giant multi strand wiring would not seem to be much of a power savings.

I do not know of any oem rv that runs multiple inverters.

Even 110 volt wiring consumes some power.

Unless you have a non inverter small rv and just trying to get some power to something?

If someone is going to post about idle current and efficiency levels please compare the exact purported power saving and then factor in exactly how much power the 12 volt cabling consumes to hook it up?

Unless you are not intending to replace the main inverter with a full sine wave unit?

A 95 freedom can not be fit with a BTMS. Never will charge the batteries correctly.

Both mk and lifeline state that their batteries require a BTMS charger

Re: Pure sine wave inverter

Reply #3 – May 21, 2019, 07:17:10 pm

Larry, our full sized Samsung uses about 170 watts while running. Maximum draw is 6 amps or 720 watts. This is pretty rare, a warm start. So if you are looking for a smaller inverter look for one in the 600-1000 watt continuous range. I am using a Victron 800VA Phoenix inverter. It produces 650 watts continuous, 1500 watt peak. The Victron 1200VA produces 1000 watts continuous, 2200 watts peak.

https://www.victronenergy.com/upload/documents/Datasheet-Phoenix-Inverter-VE.Direct-250VA-1200VA-EN.pdf

Victron Phoenix 12 Volt / 800 VA Pure Sine Inverter

You should have the appropriate sized 12v wire for the load and distance, a 12v fuse of the appropriate size at the battery end and a switch. At the output end of the inverter you should have a circuit breaker box and a circuit breaker before the refrigerator outlet. Most smaller inverters have a GFCI outlet but this will not protect the circuit in the event of a overload.

Efficiency is just one part of the power cost of using an inverter. You have to look at how much power it takes just to have a big inverter on. The Victron 800VA uses 6.5 watts to be on. A common Magnum MS2812 uses 30 watts just to be on. The Victron 3000VA Multiplus uses only 20 watts to be on.

Lots of choices out there.

Re: Pure sine wave inverter

Reply #4 – May 21, 2019, 07:32:00 pm

This 1200w inverter has been working great with our Samsung for almost 3yrs. Plenty of power for the fridge, with extra to spare for other small loads (Tv, etc), and allows us to shut down the main inverter when not needed. It has instant automatic switching to shore power and the optional remote panel provides on\off control from inside the coach.

Amazon.com: AIMS Power PWRIX120012S 1200 Watt Pure Sine Inverter, Built In...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Pure sine wave inverter

Reply #5 – May 21, 2019, 07:35:27 pm

I assumed that since the Magnum I have is a modified sine wave, I needed a pure sine wave inverter to properly run this new fridge. Am I incorrect in my assumption?

Brett, I will see if the specs show what the start up amperage is. I don't recall seeing them when I was looking.

I guess that I am more worried about damaging the unit more than a minor savings in energy at this point. That might come back to haunt me, don't know for sure.

Thanks,
Larry

Re: Pure sine wave inverter

Reply #6 – May 21, 2019, 07:36:48 pm

bdale, thanks, I will look at the link. You and I were typing at the same time.

Re: Pure sine wave inverter

Reply #7 – May 22, 2019, 06:51:29 am

You should not need a pure sine wave inverter as the Samsung turns the ac into dc so they can handle anywhere in the worlds power. I don't know about other brands but I researched it a number of years ago now when I had FT put in my fridge. That was what the said as well.

Re: Pure sine wave inverter

Reply #8 – May 22, 2019, 07:16:36 am

Quote from: John S – May 22, 2019, 06:51:29 am

You should not need a pure sine wave inverter as the Samsung turns the ac into dc...

I also remember reading that about the Samsung. I thought it sounded rather inefficient. You change battery DC power to AC with the inverter, send it to the fridge, which then changes the AC power to DC. Anyway, I put it to the test, and ran our Samsung 24/7 on the OEM modified sine inverter for about a year. It ran just fine that way. Then we upgraded to a larger capacity pure sine inverter.

But this Samsung trivia is not relevant to the OP cuz he said (in another thread): "I just ordered the Haier 9.8 top freezer refrigerator from Lowe's".

Larry needs to determine if the HAIER fridge will tolerate a modified sine AC power supply.

Re: Pure sine wave inverter

Reply #9 – May 22, 2019, 07:44:52 am

My Haier did not tolerate the prisoner 2500 well. It would go into a fault mode with alarms at random times. Since going to the Victon pure sine wave no more problems.
Always thought I had an intermittent problem with the refrigerator but now realize it was power related.
My Haier is 6 plus years old

Re: Pure sine wave inverter

Reply #10 – May 22, 2019, 09:17:30 am

Larry this is what I installed along with fuse, circuit breaker and battery switch. Works great!
https://www.homedepot.com/p/GoWISE-USA-1-000-Watt-Continuous-2-000-Watt-Peak-Pure-Sine-Wave-Inverter-PS1002/306070582

Re: Pure sine wave inverter

Reply #11 – May 22, 2019, 10:44:21 am

Techno-babble ahead.

Most Samsung refrigerators now use Digital Inverter Technology also called Variable Frequency Drive (or VFD in short). Samsung uses a variable frequency motor that can change its speed if the frequency of the incoming alternating current is changed. Thus to achieve this variable-frequency a rectifier is used to convert the incoming alternating current (AC) to direct current (DC) and then uses pulse-width modulation in an electrical inverter to produce AC of a desired frequency. This results in significantly better efficiency and electricity savings. The refrigerator compressor speeds up or slows down as cooling loads change. (Compiled from several articles)

Almost anything that uses a rectifier to change from AC to DC (mobile device chargers, laptop chargers, things like this) will work OK with many modified sine wave (multi-stepped) inverters for incoming 120v AC power. But there a lot of devices that work better and will last longer with a pure sine wave inverter. Nothing works worse with a pure sine wave inverter so for a bit more money you get a universal power source and no concerns.

For all of your mobile device charging find chargers or outlets that work on 12v to begin with. Double check what your devices need. There are Quick Charge devices that provide hight voltages and current for devices that can use them.

Amazon.com: Blue Sea Systems Dual USB Charger Socket: Gateway

Amazon.com: Quick Charge 3.0 Car Charger, CHGeek 12V/24V 36W Aluminum...

Amazon.com: AUKEY Car Charger with Quick Charge 3.0, 39W Dual Ports for...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Pure sine wave inverter

Reply #12 – May 22, 2019, 02:12:10 pm

Better yet, why does the coach have a Magnum MODIFIED sine wave? I am aware Magnum has a series of modified-sine wave inverters, but why would one choose them over sine wave. It can't be just to same one-time costs.

Re: Pure sine wave inverter

Reply #13 – May 22, 2019, 04:11:06 pm

Quote from: Barry & Cindy – May 22, 2019, 02:12:10 pm

Better yet, why does the coach have a Magnum MODIFIED sine wave? I am aware Magnum has a series of modified-sine wave inverters, but why would one choose them over sine wave. It can't be just to same one-time costs.

1. Might be to save money. Some folks are all about the bottom line.

2. Emergency replacement scenario and nothing else available?

3. Failure to do adequate research prior to purchase?

Re: Pure sine wave inverter

Reply #14 – May 22, 2019, 08:24:26 pm

Thanks everyone for the comments. I will try to locate one of the pure wave inverters local so that I don't have to wait on shipping this holiday weekend. I see from Alan's link that a 1500 watt inverter is only $20 more. Any advantages/disadvantages for the extra power potential?

Larry

Re: Pure sine wave inverter

Reply #15 – May 22, 2019, 09:41:09 pm

OK, just ordered the GoWise 1500 watt pure sine wave inverter. Prime shipping by Friday.

Larry

Re: Pure sine wave inverter

Reply #16 – May 22, 2019, 11:02:21 pm

A Magnum is capable of being a fully integrated system. Gen start, solar, battery temp system, battery management system....

Re: Pure sine wave inverter

Reply #17 – May 22, 2019, 11:29:16 pm

Good job Larry, And ya you could have purchased a full blown Magnum set up at 10-15 times the $190 price of the dedicated pure sine wave inverter. For what CaFlashBob lists you are going to spend close to $3000. There are lots of options out there for each of us to choose for ourselves based on our own perception of needs.

Re: Pure sine wave inverter

Reply #18 – May 23, 2019, 12:21:55 am

Not used to the idea that a lot of current Foretravel owners cannot and/or will not outfit their coaches with up to date equipment.

Cannot I totally understand. Or those who travel pole to pole or run their gens always. Or have large enough solar systems.

Never built anything just to get by.

Some talk price. I talk quality. And longer life.

$3k? A set of oem batteries cost almost that much.

I have found a top quality electrical system that is demonstrable to a prospective buyer got every dime back I invested as a sales manager for Foretravel.

If the purpose of this Forum is to find alternative equipment that is a good as every coach here was outfitted with new but for less money, god bless. Happy to help.

"Good things aren't cheap and cheap things aren't good." Old horse trader made me memorize that.

False economy in my experience. Especially if the coach is a "keeper."

You will replace things twice versus oem stuff. Plus the usability is less.

As a Foretravel guy I guess I have lasted too long. I can not and did not ever give a single customer who bought used coaches from me less than what Foretravel sold new.

IF I had cut corners the owners would have figured it out and that would cost me and my store a lot of repeat sales and profit margins and my phone would have rang more with unhappy owners.

I assume anyone looking at used coaches that is an a experienced owner would discount the price they might pay if substandard equipment is present. Barry's web site shows what was in these new.

I sure did. In many ways a wholesale priced unit worked perfectly for me.

That way I could afford to upgrade the entire coach to current new coach standards. 10 cents on the dollar versus new.

The idea that I need to be 6-8 cents on the dollar versus new is new to me.

Did not realize that that many posters here do not have the wherewithal to keep up their coaches to at least the original condition.

Sorry times are that hard.

God bless. MY idea is to have the same experience as the first owner had. Or better. And every used customer I sold got that same quality.

I guess I am wrong. Get by is the key? Seems like I wasted a lot of my time posting things that are beyond the ability or interest of most or some here.

Oh well. Times change. I know what I expect a coach to be capable of. My curse.

If you don't know that's one thing. If you are financially strapped that's another thing.

Like i said. Show me how to get equal quality for less money and I am all ears.

You pay less you get less is my 35 year experience in the rv biz.

Re: Pure sine wave inverter

Reply #19 – May 23, 2019, 12:38:49 am

Quote from: Caflashbob – May 23, 2019, 12:21:55 am

Not used to the idea that a lot of current Foretravel owners cannot and/or will not outfit their coaches with up to date equipment.

Cannot I totally understand. Or those who travel pole to pole or run their gens always. Or have large enough solar systems.

Never built anything just to get by.

Some talk price. I talk quality. And longer life.

$3k? A set of oem batteries cost almost that much.

I have found a top quality electrical system that is demonstrable to a prospective buyer got every dime back I invested as a sales manager for Foretravel.

If the purpose of this Forum is to find alternative equipment that is a good as every coach here was outfitted with new but for less money, god bless. Happy to help.

"Good things aren't cheap and cheap things aren't good." Old horse trader made me memorize that.

False economy in my experience. Especially if the coach is a "keeper."

You will replace things twice versus oem stuff. Plus the usability is less.

As a Foretravel guy I guess I have lasted too long. I can not and did not ever give a single customer who bought used coaches from me less than what Foretravel sold new.

IF I had cut corners the owners would have figured it out and that would cost me and my store a lot of repeat sales and profit margins and my phone would have rang more with unhappy owners.

I assume anyone looking at used coaches that is an a experienced owner would discount the price they might pay if substandard equipment is present. Barry's web site shows what was in these new.

I sure did. In many ways a wholesale priced unit worked perfectly for me.

That way I could afford to upgrade the entire coach to current new coach standards. 10 cents on the dollar versus new.

The idea that I need to be 6-8 cents on the dollar versus new is new to me.

Did not realize that that many posters here do not have the wherewithal to keep up their coaches to at least the original condition.

Sorry times are that hard.

God bless. MY idea is to have the same experience as the first owner had. Or better. And every used customer I sold got that same quality.

I guess I am wrong. Get by is the key? Seems like I wasted a lot of my time posting things that are beyond the ability or interest of most or some here.

Oh well. Times change. I know what I expect a coach to be capable of. My curse.

If you don't know that's one thing. If you are financially strapped that's another thing.

Like i said. Show me how to get equal quality for less money and I am all ears.

You pay less you get less is my 35 year experience in the rv biz.
Yes wil l
agree times and technologies change. Very often the new stuff is better

Very often the new stuff is better.

Re: Pure sine wave inverter

Reply #20 – May 23, 2019, 01:06:33 am

I assume the small inverters are not UL listed? If it causes a fire your insurance may not pay. Your insurance can sue you for the loss. DOH requires UL appliances. RVIA requires UL. Or equal.

The idea of installing a non tested high capacity electrical device in my coaches basement is a no go.

Been in the burn ward long ago.

Tell me that some kind of test sticker is on these?

Re: Pure sine wave inverter

Reply #21 – May 23, 2019, 05:41:39 am

You can get a Magnum MS2812 with the interface for about $1700 if you shop around,yes you can buy more devices but this will
work good,was reading the Magnum manual and if your generator is not set up for auto start the auto start module may not work.

Barry,it does not matter or serve a purpose why his coach had a modified sine wave,it has one and he wants a better one just
help the guy.

Re: Pure sine wave inverter

Reply #22 – May 23, 2019, 07:17:37 am

I regret buying a cheaper Chinese inverter. It's still working today, but it does not perform as advertised.

Re: Pure sine wave inverter

Reply #23 – May 23, 2019, 07:44:47 am

Victron IS a fully integrated system. Gen start, solar, battery temp system, battery management system. All capabilities are there when choosing the right components.

I'm running integrated Victron invertor, temp sensor, solar controller, and color control panel.

I can set charging profile to anything I want, down to tenths of volts desired. When at the coach I can check on status via display panel or the Bluetooth app. When away from the coach I can check on status via internet connectivity to the Victron using their app.

Victron is fully integrated. As are some other systems. Having choices of FULLY INTEGRATED SYSTEMS is good for consumers.

Re: Pure sine wave inverter

Reply #24 – May 23, 2019, 09:24:29 am

It's fascinating to read the Magnum vs Victron battles between Roger & calflashbob. Based upon my experience and the experience of others here both are excellent systems and worthy of consideration. We have a Magnim 2812 and it performs flawlessly, while others have a Victron snd are similarly pleased.

Affiliate Notice