Author Topic: Demonstration of Generator Support  (Read 15896 times)

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ChrisOlson

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Demonstration of Generator Support
« on: January 09, 2013, 07:31:48 PM »
It is surprising how many people I have talked to (most of whom have Outback inverters and have never heard of it) that do not understand what generator support is all about in an off-grid inverter. And I've talked to other folks who have heard of it but don't think it's all that important to have. And yet others who have heard of it and would like to have it, but have never seen it work in a real live installation.

So I took the opportunity to make a video with a live demonstration of how it works.

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Frank S

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Re: Demonstration of Generator Support
« Reply #1 on: January 10, 2013, 05:06:27 AM »
 Chris Thanks for posting I am truly impressed which is not to say much because any good system design engineering impresses me, since I so seldom see it anymore.  Just looking at your video it would seem to me that you have a state of the art system now.
 And when you set up your co-gen with the AC compressor you will have a system of dreams.
Maybe if the folks at Outback or the others were to see this whole new mind set for off grid energy production might be perused with more possibilities of plug & play multiple AC & DC input sources
 I believe you now have  a large solar + battery bank with water heating dump load coupled with more than a few wind generators  and your Honda all coupled together  with the probability of a go-gen with the 4bt in the upcoming summer  And you may have other solar usages  installed as well I donít remember .
 Great work
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ChrisOlson

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Re: Demonstration of Generator Support
« Reply #2 on: January 10, 2013, 12:42:05 PM »
I would bet that if you did a random survey and asked people what the most expensive thing is about living off-grid that you would not get the right answer from most folks. It is batteries. Not solar panels, or inverters, or controllers, or generators, or fuel in the generators. Batteries.

Where generator support in an off-grid inverter comes in, is allowing you to buy the bare minimum in battery capacity to run your normal daily loads and let the generator help with the big stuff instead of just throwing more batteries and solar panels at the problem. Many folks consider it the "pinnacle" of off-grid to not have to run their generator. In reality, that generator fuel is a lot cheaper than the extra battery (and RE generating) capacity it takes to never run the generator.

In most off-grid homes the normal loads are pretty light, and the heavy draw stuff is very intermittent. Instead of spending the extra money on batteries and multiple inverters to meet the peak demand, generator support is a lot cheaper. So it not only saves you money on batteries, it also saves you money on extra (or bigger) inverter equipment.

And the last thing it allows you to do is save money on generator fuel. Too many off-grid people have a 10, 12 or 14 (and some even over 20) kW generator on a XW6048 inverter or similar. This is ridiculous. The generator should not be any bigger than required to get either maximum charging amps from the inverter, or C/10 charge rate for your battery bank, whichever is smaller. Running a 8 or 10 kW generator to charge batteries with a 6 kW inverter is like using a semi to haul an armload of wood

Inverters that only have generator pass-thru support (aka Outback FX-series or Magnum MS/MS-PAE) are limited to either what the inverter can run, or what the generator can run. And that means if you want to power a 6 kW load with a 4 kW inverter you need a 6 kW generator - and you have to run that 6 kW generator for charging when you only need 3,500 watts to max out the charger in the inverter. With gen support you can save the gen fuel and run your 3,500 watt generator for battery charging, and still power that 6 kW load with ease.

It's not about having the biggest there is.  Generator support is about using the smallest inverter and smallest generator combination possible to run the biggest loads with the minimum in battery capacity required.  When you live off-grid if you subscribe to the "Go Big or Go Home" theory - you will pay dearly for your mistake.  It is much more prudent to apply proper engineering and equipment to the job to get it done at peak efficiency and least cost, because living off-grid is anything but cheap.
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kevbo

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Re: Demonstration of Generator Support
« Reply #3 on: January 10, 2013, 04:47:34 PM »
Chris, you never fail to impress me with looking at the big picture, system view, whatever you want to call it.  When the fuel is free it is all too tempting to overspend on what is needed to "burn" it.  Because the fuel is free, you must pay close attention to the capital and maintenance costs.

Even when you look at large utilities they often have some expensive plants to carry peak loads...which used to be natural gas fired turbine plants, but now that gas has gotten a lot cheaper, they are not so reluctant to bring them on-line as a few years back.

You are also adding diversity to your system, so you are not without power when the once-in-500year ice storm takes all your windmills off-line.

One thing I haven't heard you mention is the time-value of whatever money you tie up in the system.  Even if you don't borrow money for the energy-system, that is money you could devote, or not borrow for other things, so you really need to tack an interest rate onto the cost of system even if you don't borrow to pay for it.  Of course your cheaper-is-better approach just means that when you consider this, you are even better off.

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #4 on: January 10, 2013, 05:18:31 PM »
One thing I haven't heard you mention is the time-value of whatever money you tie up in the system.

Indeed the money outlay for equipment has to have both depreciation and interest figured in - none of the equipment lasts indefinitely.  The most expensive is batteries - assuming our bank lasts 7 years the battery cost is slightly over $100/month.  I figured it out once and we would have to easily double our bank size (along with bigger inverter equipment and more RE generating capacity) to never run the generator.  And then at 7 years you take it in the shorts with a $17,000 bill to replace a big battery bank.

That sort of puts in perspective how cheap using generator support to run the peak loads is, looking just at the cost of batteries.
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Windmill1

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Re: Demonstration of Generator Support
« Reply #5 on: January 11, 2013, 08:33:56 AM »
Great video
Thanks for sharing this with us. Notice you have a midnite battery capacity meter, are these very accurate. Thinking about getting one.

Great  setup,

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #6 on: January 11, 2013, 10:35:07 AM »
The MidNite battery capacity meter is quite accurate - it is a digital at-a-glance voltmeter.  So you have to expect that when the bank is at, say, 80% SOC and you put a heavy load on - the voltage sag on the bank will cause the meter to drop into the yellow, or whatever.  Then it recovers and comes back up into the green when the heavy load is off.  Using voltage to tell what battery SOC is is only accurate if the batteries have been at rest - no charge, no discharge, for at least 2 hours.  And that never happens with an off-grid battery bank.  But it tells you at-a-glance what the status is of your bank, and therefore it serves its purpose well.  I wouldn't be without it - we have ours in the kitchen next to the ICM25 panel for the inverter.

The other thing the MidNite meter does is tell you if your bank hasn't been properly charged in the last week.  If the light on the left stays green it's good.  If it turns yellow there's been a problem with not enough incoming RE power (or not enough gen charging) to keep the bank desufated.

My wife actually pays more attention to that MidNite meter than I do.  She glances on it when turning high-load stuff on to see if she's over-taxing the bank without the generator running.  And if it drops down into the red under heavy load she knows there's a problem so then she goes over and looks at the load amps on the inverter and if's below 40 amps it's OK.  If it's above 40 amps and the generator hasn't started she gets worried and shuts her stuff off and calls me on the cell phone wondering what to do.

That only happened once when I had serviced the generator and forgot to re-enable the starting relays after servicing it.  The MidNite meter was down in the red, the inverter panel was flashing an error for gen failed to start, she knew it wasn't right so she called me.  I was able to tell her what to do over the phone to re-enable those gen relays, have her clear the error and get the gen started.  And that's what makes having that stuff in an area in the house where you can monitor your system worth every dime you spend to install it.  The inverter had been delivering well over rated continuous amps for almost two hours and if it was any lesser inverter it would've already been overheated and off-line.  That MidNite meter being in the red due to severe voltage sag under heavy load is what caught her attention and saved the power from going out.
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Windmill1

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Re: Demonstration of Generator Support
« Reply #7 on: January 11, 2013, 01:12:36 PM »
Thanks Chris
I  enjoy reading all your post and all the info you have on this site

XeonPony

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Re: Demonstration of Generator Support
« Reply #8 on: January 12, 2013, 11:13:05 AM »
To me a genset is a crittical part of any real off grid system, with mine 12G usualy lastes me well over a month and it gets used fairly often top of my list is geting a system with that capability, right now I am using a hacked Noma 1800 battery back up unit, so best I got is a transfer switch :( But it does the job till I can get a real inverter!
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Re: Demonstration of Generator Support
« Reply #9 on: October 29, 2013, 06:04:03 PM »
Hello All,

Does anyone have the latest skinny on what inverters do a good/bad job with Generator Support? I am digesting Chris' great posts, sizing a couple inverters & one new battery bank, and also looking at charge controllers. My experience is with Outback & Trace/Xantrex. I have plenty of experience with power systems.

48V, -30F possible in winter, off-grid, one system needs no more than 8K of inverter, the other (in a different location) no more than 16K. Of course these sizes can be "a bit" lower dependent upon how well the Generator Support works, and I know these sizes seem high, but the numbers have been ran.

Thanks y'all!

 

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #10 on: October 29, 2013, 06:48:22 PM »
Does anyone have the latest skinny on what inverters do a good/bad job with Generator Support?

That video got deleted off my YouTube Channel.  It was done with a Xantrex SW Plus 5548.  Since I made that video we have a new Schneider Electric Conext XW Power System with ComBox monitoring, logging and remote system control



The Trace SW-series, Xantrex SW Plus-series, Xantrex (now Schneider Conext) XW and SW-series all do excellent generator support, and have for 20 years.

The Outback GS8048 Radian is supposed to have it - I spent most of one afternoon at a neighbor's place trying to get it to work.  Never could make it work right.  All they did in the Radian was re-label "Grid Support" for grid-tie applications to "Generator Support" on AC2 input.  It's a hack and keeping the generator qualified on it is damned near impossible.  In trying to get the Radian system that I worked on to work with it, it became evident in talking with Outback tech support, and in the design of the hardware, that they do not have a single clue what they are doing when it comes to getting generators to interact with an off-grid inverter system.  I finally gave up on it and decided at the end of the day that the GS8048 was designed for grid-tie, not off-grid.  Plus the Mate3 is the most convoluted mess I have ever seen in my life - actually worse than the Mate and Mate2 (I never believed that was possible).

The Outback GFX is advertised as having generator support.  I only know of one person who has tried it and said they got it to work with a Honda EU2000 inverter generator.

None of the other Outback inverters have it.  Some people claim you can get a GVFX-series grid-tie inverter to do it with an inverter generator acting as the "grid".  Outback tech support says it is not supported in the GVFX-series, and in fact they don't even support a GVFX for off-grid use at ALL.

The Magnum MSH4024RE has generator support and is now released for sale.  I have no experience with the Magnum, so can't tell you if it works or not.  None of the other Magnum inverters have it.

The SMA Sunny Island has generator support.  Also have no experience with them, so can't vouch for it.

The bottom line is that if you design your system to use it for peak load management, and have a decent sized system, there is only one inverter that you can buy with 100% knowledge that it will work, is fully supported by tech support, and works out-of-the-box even with generators with high THD and freq and voltage out of range - and that is the Schneider XW-series.

The XW-series inverters are split-phase for the North American market.  Getting gen support to work with a split phase system where you can have leg imbalances of up to 75% between L1 and L2, and having it work every single time, is no small feat.  Gen support is easy on single phase 120V output inverters.  Not so easy on split-phase.  The engineers at Xantrex (now owned by Schneider Electric) have years of experience with it, plus they know and understand why off-grid people use it.  So the Conext XW and SW-series is the only one I can recommend if you want it to "just work".
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kitestrings

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Re: Demonstration of Generator Support
« Reply #11 on: June 03, 2014, 11:43:15 AM »
Hey Chris,

Now that you've had the Conext equipment awhile (couple years?), I was curious if your opinion/experience has changed much (for better or worse, or just what you expected)... other features you like, hate or have learned to live with maybe.

I was looking at their specs a bit.  Had a couple questions.  Not that I'm rushing out to by anything, just curious mostly:

It looks like the 4 kW unit is 24V, and maybe is only available at this input voltage.  Is that right?  I wondered why not 48V (which I'd thought was your nominal bank) as many offer.

Does your aux generator synch up pretty well, and does it ever not?  I was wondering what happens if the generator has any sort of problems (governor problems, iced-up intake, rats-nest in air filter, you run out of fuel).  I assume there are frequency and voltage parameters, outside of which it doesn't connect and contribute.

The standby load losses seem high.  40 watts?

Regards, ~kitestrings

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #12 on: June 03, 2014, 06:27:47 PM »
The equipment is fantastic.  It is so dead reliable, and so much like having utility power, that we don't even think about it anymore.  No flickering in the lights when the A/C compressor kicks in (yes, we even run a 1.5 ton central A/C unit with it), it will handle significant overload for quite awhile, has no de-rating based on temp, and the entire system (solar controllers, inverter, AGS, ComBox, SCP) integrates better than anything else I've ever seen or worked with.

The 24V unit is only available as 4.0 kVA.  The comparable 48V unit (XW4548) has a few more watts capacity and is the same price as the 4024.  I suspect they don't offer a 4.0 kVA 48V unit because of the 4548.

You can set the allowable voltage and frequency limits for your genset, and get the XW to sync up with it.  BUT that "dirty" power is passed on to your loads too.  So it pays to buy a decent generator.  If the genset is operating and it falls outside the allowable voltage and freq that you have set, the XW will disqualify and take over.  Then it will analyze whether or not the generator is stable enough to re-sync with it.  If the genset is operating in allowable limits, no load, the XW will re-sync with it and load it according to what you have the Gen Support level set to.  But if there's a rat's nest plugging the air filter, within milliseconds it will "spit" the genset off and take over again.  It will continue to try this several times (I think six) and if the genset don't straighten out and play decent the XW will shut it down (assuming it is controlled by the AGS) and flash a warning (red light) with a message on the SCP telling you that the genset is no good and you need to fix it.  If you have a ComBox it also sends an email to your cell phone telling you that the genset is fricked up and it disabled further auto-starting of it until you get around to fixing it.

The XW is a big transformer-based inverter.  Just the transformer in it weighs about 65 lbs - more than a whole Outback FX-series, or Magnum PAE, inverter.  Big transformers like that eat up quite a bit of power when idle because there's a lot of copper in it.  But that copper mass is also why it can handle significant overloads for a long time, and why it has such rock stable power output.  Ideal loading is 20% rated continuous capacity or better.  So if you buy one and your normal loads are only 500-600 watts don't buy a 6048.  Buy the smaller one.  The smaller one will still handle your biggest loads using gen support, and be more efficient for the >90% of the time that your loads are at baseline.

The thing I like about it is that my wife can be doing laundry with the washer and electric clothes dryer going, decide to make a pizza in the oven (electric range) and turn that on, the well pump can kick in, and the inverter still handles all this, along with all the other stuff going, even though it is grossly overloaded.  It waits for one minute and if something don't get turned off it fires up the gen, warms it up and syncs with it, and transfers 4.0 kVA of the load the genset to reduce the load on the inverter back below rated continous.  It is so seamless that we do not even think twice about it anymore.

So overall I consider the big XW to be pretty much the "Cadillac" of off-grid power.  It is a proven design that has been around for many years, they rarely break, Schneider Electric now has a tech support dept that far outshines anything Xantrex ever had, and the integration of the system components has not been matched by anybody else.  I am extremely pleased with it and not a single complaint because the XW has basically given us utility-scale (and quality) power in an off-grid situation.  And it does it without having to stack inverters, and buy a lot of extra batteries to power stacked inverters.

I put the pencil to it long ago and genset fuel for when you need overload capacity is less than 30% of the cost, long term, that JUST the extra batteries would cost to power stacked inverters at the same capacity as the XW+Genset during gen support operation.  The longest I have ever seen the genset run (logged by our ComBox) is 3 hours 53 minutes one time on gen support.  And that was for Christmas when my wife had EVERYTHING in the house fired up to cook Christmas dinner for the whole family that was there and using a totally electric kitchen to do it.  So the genset burns about .65 gal/hr at that load and we used 2.6 gallons of gas that cost like $10 bucks.  Big whoop, ya' know?  If you look at it realistically, you could spend $4 Grand on more batteries, and $3,600 on another inverter to power all that.  But what is the chances that you can recharge those batteries on RE power later?  Nil to none.  We used something like 32 kWh in that four hours, and even with all the expense in extra batteries and another inverter, there is a greater than 95% chance the genset would still still start to charge batteries.

And in a nutshell, that is why I designed our system to use gen support as an integral part of it.

kitestrings

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Re: Demonstration of Generator Support
« Reply #13 on: June 03, 2014, 06:56:35 PM »
Thanks for the update.  Sounds like a great system, and the concept makes perfect sense.

Our electrical loads are much lighter, but we rely more on LP than I'd like to; plan to.  At ~$45/MMBtu that's not the deal your dad got for hunting camp anymore.  A lot of folks are off-grid but they've only traded utilities.

How, or do, your Classics integrate with the Combox?  Oh, and what's the AGS, auto gen start maybe?

~ks

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #14 on: June 03, 2014, 08:28:26 PM »
Our electrical loads are much lighter, but we rely more on LP than I'd like to; plan to.  At ~$45/MMBtu that's not the deal your dad got for hunting camp anymore.  A lot of folks are off-grid but they've only traded utilities.

We burn gasoline and diesel fuel in our generators.  But we didn't end up off-grid to prove a point about "going green", reducing our carbon footprint, or saving the planet or anything like that.  Some folks think it's a sin to run a generator off-grid, while they cook on a propane stove.  Well, we don't look at it that way.  For us it's all about economics, efficiency and convenience.

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How, or do, your Classics integrate with the Combox?  Oh, and what's the AGS, auto gen start maybe?

The Classics do not integrate at all.  They are pretty much standalone.  The XW system is always in sync.  There is a hierarchy of sorts on Xanbus that determines certain things, such as which component is the primary charger for instance.  If there is solar power available, then MPPT1 becomes the primary charger and all other components in the system that can charge batteries (inverter included) follow it from bulk to absorb to float, etc..  If there is no solar power available, then inverter #1 becomes the primary charger (assuming a situation with more than one inverter).  You don't have to set this - it's totally automatic.

If you want to change the setting for Absorb V, for instance, you only have to change it in one thing - the change is automatically made on the other components in the system that can charge batteries and use that setting.  It is called "cascading" the settings over Xanbus.  So you don't have to change it manually in every component.

During charging with the MPPT controllers, instead of each controller showing their individual output on their screens, it shows the total System Output to the battery in watts and amps.  So you don't have to stand there and add up what each controller is outputting to figure out what your system is producing.  Although you can have each controller show their individual output too.

These are just some examples that are really the tip of the iceberg on how the XW System is a total integrated power system.

kitestrings

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Re: Demonstration of Generator Support
« Reply #15 on: June 04, 2014, 10:47:12 AM »
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But if there's a rat's nest plugging the air filter, within milliseconds it will "spit" the genset off and take over again.

On a slight side-track- we have a 4 kW Onan gen-set.  Nice little unit, LP, low-speed, live PTO (I used it to split my firewood), always starts...well most always.  We have it where it can be started remotely from either the house or shop.  One fall day I hit the button and it fired once, then made an odd 'ringing' sound like the gear on the starter had misaligned or some such.  On subsequent attempts there was no fire at all.  Went to the shed to find hair, nest material and a little tail hanging out of a void about the size of your finger where just above the starter.

I spent most all of one day - unhooking everything, schlepping it to the shop, and breaking it in two just to replace a little fiberglass wand with two pencil sized magnets that trigger the coil on the thing.  When I spoke to a guy that does RV work, he said "Yeah, we see that all the time.  The like the warmth of the oil reservoir."

Thanks for all the feedback.  I'm going to read up on it a bit more.  Dandy set up though.

~ks

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #16 on: June 04, 2014, 10:17:08 PM »
A mouse might be able to disable the starter on one of those old Onans, but otherwise I don't think you can kill one.  They're not really the most fuel efficient generator ever designed.  But they're one of the toughest.  And their windings are really good too and and they put out super clean power.  I've seen those old Onan generators put out cleaner power, with less THD, than you can get from the utility.

kitestrings

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Re: Demonstration of Generator Support
« Reply #17 on: June 09, 2014, 11:44:35 AM »
Chris,

I thought you might be interested to note:

1) I found your youtube clip still floating about, after watching one of the SE product overviews:
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http://www.youtube.com/watch?v=q5XFDaEMHAQ

2) So then I was curious what the thing costs (which I found several commons spots), but I couldn't help notice that Amazon is saying that the 6048 is discontinued - maybe they're supplier - I saw nothing on the manuf's site to confirm this.
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http://www.amazon.com/Xantrex-Inverter-Charger-Discontinued-Manufacturer/dp/B002MW8HU4/ref=pd_sxp_grid_pt_0_0

Regarding generators, I had an old Onan welder/generator unit years ago.  It was bare-bones, not even a recoil start on the thing, but tough as nails.  It was a lot like starting an old Farmall, which based on sound you never thought would occur until suddenly it was up and running.  We then had a Honda for a few years, and finally went to this Onan.  My preference is the slower speed (1,800 rpm) units, if for no other reason than the noise.  There's something about the higher speed units that grates on me; just a higher pitch.

~ks

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #18 on: June 09, 2014, 12:00:43 PM »
Yes, the XW has been replaced by the XW Plus series - I believe they are the XW+7048 (230V 50Hz) and XW+8048 (120/240V split-phase 60Hz).  The XW Plus series is the same as the XW with higher thermal limits.  I believe the XW4024 is discontinued in favor of the Conext SW4024.

The new XW Plus inverters were just launched last week:
http://www.prnewswire.com/news-releases/schneider-electric-launches-the-next-generation-of-the-highly-successful-xw-hybrid-inverter-261801441.html

Homesteader1

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Re: Demonstration of Generator Support
« Reply #19 on: February 05, 2015, 04:32:28 PM »
Hi Chris,
I just read the generator support string and watched the video. I'm interested in the Outback autotransformer that you are using to help balance the loads. Did you install this only after you figured out you had load imbalance or was it something you installed from the get-go? I think this particular autotransformer either steps up or steps down the voltage right? How is it connected to your system? It has two 25A breakers so is this a limiting factor from either your generator or the Xantrex system? The reason I'm asking is this: I'm about to lay out a whole lot of hard earned bucks for either an Outback Radian8048 or the Xantrex XW6848+NA. I will run a diesel generator and want as few problems as possible. What are your thoughts?
Dale

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #20 on: February 06, 2015, 10:45:11 AM »
Hi Dale,

I originally had that transformer when we had our old 120V SW Plus 5548 to provide 240V power for the house.  When we went to the XW it was no longer needed so I put it in as a balancing transformer.  The XW does not need a balancing transformer, so I later took it out and it is no longer used.  While I can't vouch for the Radian, the XW can handle HUGE imbalances and still keep the generator balanced on AC2.  The XW inverter is an absolute beast.  It is heavy, and it puts out well beyond its rated power (8+ kW intermittent) for up to 30 minutes with no issues.  You basically can't kill one.

You will find that the best size for your generator with an XW is anywhere from 4.0- 6.5 kVA, depending on how much overload and surge capacity you need for peak load support.  We use a 4.0 kVA set and let the inverter handle more of the load.  The larger the genset, the peak load will go more to the generator and less to the inverter.  IF you can keep a larger genset loaded at 80% rated, or better, during peak then the larger genset will pay off.  We have never been able to, since the peak loads are so intermittent, so the 4.0 kVA works well for us.  I can do welding with my Lincoln 225 in the shop with the welder at Full Dawg, while my wife has all the other loads in the house going, without causing the genset to start.  That's because the welder, while a big load, is intermittent so the inverter operates on its overload surge capacity where it will deliver 12+ kW for 30 seconds.  Only long continuous overloads will cause the generator to start.

IF you use a diesel for peak load support you're going to have to come up with a way to keep it preheated 100% of the time, just any other emergency standby diesel generator.  You might see standby diesels sitting by a hospital or something, but what you don't see is that that genset has about 3,000 or more watts worth of block heaters going in it that keeps it at full operating temperature 24/7.  I use the hospital example because facilities where life support systems are in use is one instance in standby generators where the backup power source is required by law to start and accept full campus load within 11 seconds of a power outage.  The electric bill to keep a pair of 1.2 MW Cummins QSK's at full operating temp 24/7 for a hospital standby power system is over $1,000/month - JUST for the block heaters.

The genset duty on a XW when used for peak load is the same.  When the genset comes online due to inverter overload, it starts it, lets it stabilize for maybe 30 seconds, then the generator must able to go to it's full surge rating when it accepts load.  The inverter then regulates it back to the gen support setting for continuous load.  That will pretty much kill a diesel genset that's still cold in short order.  If the engine isn't preheated, the combustion chamber temp is too low for the engine to deliver full power during that initial loading.  That's why we use a gasoline air-cooled genset for peak load and use a diesel for high continuous prime loads.  Air-cooled gasoline engines will take incredible abuse when they're still cold.  Diesels won't.

In the end the only difference between the XW and XW+ is different thermal ratings and a new paint job to signify Schneider's transition from the old Xantrex brand to the Conext line.  The different thermal ratings allow Schneider to use the same rating method that Outback and Magnum use to reflect the inverter's overload capacity vs ambient temp.  The XW6048 and XW+6848 are identical internally.

Homesteader1

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Re: Demonstration of Generator Support
« Reply #21 on: February 06, 2015, 06:08:09 PM »
Hi Chris,
Thanks so much for your reply, it really helped me to make my decisions regarding the Schneider equipment. In the spring I'll be installing 5.8KW (Solar World) solar and a 1.8 KW (Jacobs) wind generator. I'll initially stay connected to the grid but not sell into the grid. Then when I'm comfortable with what I've got I'll probably cut ties with the grid altogether.
Regards
Dale

gww

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Re: Demonstration of Generator Support
« Reply #22 on: February 06, 2015, 08:17:19 PM »
Chris
I haven't seen you around alot lately.

Quote
We burn gasoline and diesel fuel in our generators.  But we didn't end up off-grid to prove a point about "going green", reducing our carbon footprint, or saving the planet or anything like that.

I don't care why you went off grid.  You have to live and learn because you are off the grid and I for one get some pretty cheap advice without having to take the chance and do the experments myself.

So I don't care what your motives for living the way you do. I just hope you keep sharing what you have learned.  And I thank you every time you do.
gww

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #23 on: February 08, 2015, 02:30:00 PM »
Chris
I haven't seen you around alot lately.

Been quite busy with a lot of projects, and just don't have the time to post much here.  Every once in awhile I get an email from a thread I was on, and that reminds me to check in and see what's happening.  LOL!

Otherwise not a lot new here in northern Wisconsin.  Weather has been agreeable this year - not near as cold as last year.  And while we've had decent snow, not enough to get the snowmobiles out.  We had a LOT of snow in November, but then got some warm days and some of it melted.  And lots more cloudy days this year - our year over year solar production has been down to about 70% of what it was last winter since Nov 1. 

Bruce S

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Re: Demonstration of Generator Support
« Reply #24 on: February 09, 2015, 10:11:02 AM »
ChrisO;
Come on down the the sub-tropics of St Louis :-) mid-sixties yesterday!
Hows the bike? not much time to ride with the "FEETS" of snow y'all been getting lately!

Cheers
Bruce S
A kind word often goes unsaid BUT never goes unheard

ChrisOlson

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Re: Demonstration of Generator Support
« Reply #25 on: February 09, 2015, 11:30:11 AM »
Come on down the the sub-tropics of St Louis :-) mid-sixties yesterday!
Hows the bike? not much time to ride with the "FEETS" of snow y'all been getting lately!

Hi Bruce,

Yeah, there's a guy named Jim that's from O'Fallen Missouri on the Farm Net on the ham radios.  He checked into our net last night and was telling about that.  Another guy checked in from Kansas and said it was 70 degrees there yesterday.

Oh well, yeah I been sitting on the bike every now and then dreaming about spring.  It's sitting in the shop and I could ride it except for salt on the roads and some treacherous ice to get it from the shop to the road.  My wife has hers in the car garage all covered up and I told her the other day I should put the battery charger on it to make sure the battery stays up.  She told me I'm not to touch her bike - it's hers and she doesn't want me "Tim Tayloring" some different engine in it or something   :o

Homesteader1

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Re: Demonstration of Generator Support
« Reply #26 on: February 13, 2015, 07:12:41 PM »
Hi Chris,
Well I ordered the Schneider equipment and will spend much of this spring/summer installing and tweeking my new system. I've wanted to do something like this for years and now finally will be doing it. I hope you don't mind me asking more questions along the way. I will be putting an old Jacobs 1800W wind turbine into use and I know it will not likely produce much compared to my 6Kw solar system but I'm an (retread) electrical engineer by training and I just cant imagine being happy watching a solar system do it's thing. So the wind turbine will be my mental exercise machine. I have a Carter 80' monopole tower that it will be mounted to. My question for the day is this: Aside from the obvious technical issues of "How" to mount it, have you ever heard of anyone mounting two wind turbines on one tower? I want to experiment by making my own generators but don't want to put up additional towers. This tower can be lowered in 5 minutes so the drudgery of raising/lowering the tower don't come into the picture. Just wondering...
Thanks
Dale