XW 4024 - thinking of generator failure

nkin · December 2020

Greetings All, We’ve been very happy with off grid solar, running our 240 volt XW 4024 with a Honda EM6000GP generator. Since it’s about 17 years old, I’m worrying about it’s failure. It could leave us with inadequate solar (Vermont) for weeks.

Impressed with Honda, I also have a EU2000i for camping trips. My first question -- for when my bigger generator fails -- is whether I could at that time use the 120 volt generator to run my 120 volt well pump simply by powering the correct two supply wires (and ground - in 4 wire cable) running underground to the 240 volt inverter. This would be easy to do in the generator shed, with an adapter and very little special wiring. But, crazy?

The naive, perhaps foolish/stupid, hope is that this temporary hookup would power one 120 volt side of my 240 volt distribution panel - without damaging the inverter or anything else. Otherwise I could make a temporary connection for just the pump, within the distribution panel, I suppose. [powering one “side” of the panel at a time would, in theory, add flexibility]

Since the forum discussion I found dates to 2012 - and since Honda has sadly discontinued its propane generators - I’m also wondering if anyone has recommendations for 240 v propane generators these days. I like the looks of the Kohler 6vsg, but it is expensive and would lock me into service by an expensive local dealer. An Onan 9500 watt dual fuel generator seems possible but requires choke, not handy for remote starting inside house - and not particularly well reviewed online. Hutch Mountain conversions (apparently well recommended) don’t seem to handle 240 v Honda’s but there seem to be other (more generic?) options.

[Would like diesel - but no easy way to protect oil tank from subzero weather.]

Thank you. Nkin

Dave Angelini · December 2020

You might consider also that the XW4024 is long out of support life and that is what I would be most concerned with. You can get a genset 7 days a week in NA. The CSW 4024 is the replacement but it is not as good as what your XW was spec wise.

Graham Parkinson · December 2020

Regarding feeding your pump from the Honda 2000. First question would be what is the surge requirement on pump startup and is this within the Honda 2000's short term load capacity?

The safest way to feed the pump in the event of failure of your big generator and not having enough energy in the battery bank to run it by inverter would be to use a transfer switch. You really don't want to be backfeeding your inverters AC output from another AC source like your generator. So I wouldn't wire your generator to one side of your panel if the inverter is still connected and could possibly be energized. A transfer switch on the pump feed would allow running the pump off either the 120 VAC generator direct or the inverter but would keep them separate.

However if your big generator does fail, depending on how you have your neutral circuits wired, you could make a pigtail plug and feed both sides of your panel from your 120 VAC generator, but again you would have to remove the pigtail if you wanted to run the inverter.

Another and better option is an autotransformer to boost your 120 VAC generator to 240 VAC, you'd have to dial back your inverter charging rate though.

Lastly, propane conversions are available for the EU7000 which makes 240VAC. The trick in starting propane generators in cold weather is to use a propane diaphragm with a 12 V solenoid operated primer valve connected to the starter motor circuit. Check out the US Carburation website for these.

nkin · December 2020

Dave and Graham, I’m not really looking to spend even more big bucks until forced. I mainly want to be able to “limp along” during the time it takes for a fix - whichever failure comes first. I wonder how often such Xantrex inverters fail before the 25 year life hope for accompanying solar panels? Gosh, time flies, failures loom!

Not being an electrician, I’m confused by Graham’s “back feed” term. [I considered my concept “front feed”.]. Since the XW4024 is currently fed by a four-conductor cable plugged into 240v outlet on the Honda, I hoped the XW could tolerate a 120v “loss” equivalent to simply disconnecting one of the two hot conductor feeds it now enjoys. [Not something I’d try without expert confirmation.].

I’d been watching load wattage on my control panel, thinking it (about 1200w) was well within EU2200i running capacity - BUT I now fear the surge is too high and too brief to be shown on that simple panel. Sources seem to suggest up to 2-3x running watts. - which would put me out of business.

It sounds like disconnecting XW and hooking up temporary “panel pigtail” may be my best option - when I borrow a larger gasoline generator. Temporary solution for either component failure.

My factory-propane Honda has worked wonderfully down to VT coldest, perhaps -20f. I think the Kohler would too, but seems like it may have more sophisticated/expensive controls than I really need to simply charge low batteries and run heavy loads, under manual direction

Making progress. Thanks a lot for the help.

Nkin

mike95490 · December 2020

I think the XW needs a 240V feed to charge and pass loads thru. Dave would be the authority on that.

So you either would need a 120 - 240V transformer of some HIGH QUALITY type ( mine is a 4KVA @ 115 lbs ) because the inverter generators choke on poor inductive loads or a generator with true 240V output , which you would need if your inverter conked out at some point

Dave Angelini · December 2020

It really is the input relays that are the weak link on any inverter/charger. xw4024 would last just about forever if it had SPD's and no genset input. Abused by gensets and user configuration issues. Unattended operation adds damage as it is never heard by the ears.

In a perfectly configured gen app, the user would run the first hour charging the batteries, then bring on AC loads, and finish with the sun.

This often does not happen though. The gen starts, in a minute or so the relays get banged with house loads, the soft start battery charger comes on. The gen is overloaded. The relay opens under full house and charger load. The process repeats. Often the user is inside and does not even know it. Like a good cat with 9 lives, the relay can take this. Until it can't!

AGS makes this even worse ! The fire danger from poorly installed gensets (not bolted down)
I see this all of the time, especially the last 5 years with the fires in the Sierras. I am waiting hear of a wildfire to start another wildfire from a genset.

Sorry for the Rant! Be safe out there! Don't buy used inverter chargers

nkin · December 2020

Thank you Mike and Dave,

Big help. I think I’ll just arrange to borrow or rent 240v when necessary since my little guy is too small.

My control panel, batteries and inverter are in handy interior location, with generator in a shed 100’ away. When I want to run something like coffee maker or microwave it’s easy to reduce the charge percentage enough to allow use precisely when I want it. Pumping water to 500 gal tank conveniently can wait until sun and battery state allow it (most often by generator VT winters). I’m almost always able to avoid overloads but will now try to be even more cautious, knowing about relays, Dave. Had to replace control panel after nine years, perhaps from overuse - but that’s relatively easy and inexpensive. [It would be nice if Xantrex/Schneider designed CP to provide load wattage without so much button pushing, while adjusting charger percentage. Can’t have everything.]

Nkin

Dave Angelini · December 2020

The button pushing is an issue with the SCP. I can't read it anymore without help at my age....

Does not sound like you would want to see something like this below on a laptop or smart phone. Schneider uses the gateway to get data out to your home network or smartphone by wifi or network cable. There is more data available than most people need. Below is the home screen that comes up without pushing buttons. Well maybe a few

Image: https://us.v-cdn.net/6024911/uploads/editor/3p/ryws8ciu6ips.png

nkin · December 2020

Dave,

Interesting. Thanks. I have similar trouble - squinting and guessing at those little numbers. Is what you illustrate something which could be added to my XW4024 system without major complication/expense? Perhaps a cable to a laptop?

Nkin

Dave Angelini · December 2020

Yes just a network cable. They are in the store here but $500. They can also Wi-Fi the system info out to your network without running cables. Tablets smartphone laptop.

On your SCP, you said it was alot of buttons to get around. For offgrid alot of folks did not set-up SCP correctly. It defaults to AC1 the grid. If you program priority to AC2 you will see the genny on the system home screen instead of the grid. The bottom line on system status or home screen will be AC2 instead of the useless AC1. It will show what is coming out of genset.

A Even Vermont has Costco right? You can get a gen there 7 days a week and they will deliver for free, I think! I always say that but there are places offgrid that just are not served. You one of those?

nkin · December 2020

Dave,

Thank you. My SCP seems correct with no grid power shown. Just have to go to advanced settings and a few lines down to change charger maximum up and down.

i’m curious about this $500 “cable”. Why so expensive? Where can I read more about the capabilities?

I found Honda em6500sx available nearby. Have it running for quick fix while they see what it takes to get em6000gp up and running again. Ideally, I will have someday propane power and gasoline backup.

(Yes we have a Costco nearby in NH.)

Nkin

Dave Angelini · December 2020

Welcome ! Send me a client please! I charge a small fee for design and a small one to get equipment/help install by text/email. I often use the store here for equipment. It is guaranteed and background is 300+ offgrid homes back before your Xantrex and before they bought Trace Engineering.

You can find out about the gateway below. It can run without internet and wifi your system to a phone, tablet, or laptop. It could allow me to remote view and help get settings/config correct. You can allow someone to read your system, or read/write.

https://solar.schneider-electric.com/product/conext-gateway/

nkin · December 2020

Thanks again Dave. I think I’ll content myself with old inverter and SCP until forced to fix or replace. Since that could take weeks, we’ll just be prepared to live without batteries and schedule our generator use — the way a lot of folks get by around here. In the meantime we’ll try to follow your advice and avoid abusing our relays etc.

We’ll keep your offerings in mind for future replacement. At this time, however, do I correctly understand that the CSW 4024 is the best close alternative - meaning XW4024’s are unavailable? How problematic would it be to change brands for specs closer to what we’re replacing? [looks like significant drop in power capabilities]

One more please - - do I infer correctly that service - such as relay replacement - is not likely a good option when XW4024 fails?

Nkin

Dave Angelini · December 2020

Just use your ears when running the genset. If you see the charge amps drop to zero, and lights do a flicker, you have shortened the relays life. Genset should sound smooth. Use the gen breaker to shut down input to xw ac2 in when you want to shut the beast off. Do not just turnoff genset!!!

Your grey box XW (they are now white but no 24v now) has been out of support since about 2011. No factory service/support until after the last persons warranty ran out. There are aftermarket people who can change the relay. The if, is if the PCB has not been burned up. Then you would need a scavenged pcb from an old unit. This is too unreliable to me and many of my clients unless they use the old as a spare to a new unit. There is a place I have used on the west coast and one in Minnesota for repairs. When I last looked, nothing in the East. You would definitely have to ship the 125 lb xw on a pallet also to get repaired. Two person lift off the wall and the replacement CSW is 1/2 the weight.

The CSW is a good replacement for you and it can run from a 120vac genset alone or 120/240vac gennies. The 4024 CSW is not going to have the surge or high output battery charger, It does not sound like you need that though. To each their own on going thru winter without power. Some are quite content to look out the window at the snow in candlelight

The solstice is in about 7 days. Enjoy!

https://solar.schneider-electric.com/products/discontinued-products/

Image: https://us.v-cdn.net/6024911/uploads/editor/q3/hu6he8qzl9vu.png

nkin · December 2020

Dave, Interesting. Thanks.

Apparently the “quality” of the electricity is potentially damaging while generator rpm is going to zero? Had no idea. Good to know and avoid. Will try to correct habit.

I was under the impression that I could simply turn circuit breakers in order to get generator power directly to my house panel, without inverter. That’s what I was planning for when inverter dies. Will have to check.

You’ve been very patient and helpful. I hope you don’t mind yet another question - for someone “over his head” - in interest of longer inverter life.

My new generator is capable of 5500 watts continuous power, 6500 maximum. For one “round“ example, if my inverter is displaying a charge current of 100 amps at 29 volts, I’m guessing it must be drawing about 100x29x1.1 (10% for heat) = about 3200 watts. In theory, that might leave me about 2300 watts to run a 1200 watt pump, exclusive of surge (which I don’t know how to measure). Xantrex claims XW4024 can handle up to 8000 watts for 20 seconds, possibly enough.

[I seem to remember that the XW inverters have some capability to draw power from batteries when generator power is inadequate - but that seems unrealistic in this scenario. Irrelevant?]

Do you think I’m abusing either generator or inverter by turning the pump on without lowering charge current further?

Nkin

Dave Angelini · December 2020

The XW is 17 years old? I think 15 years is max from when they came out in 2005/6. You must be doing good things (up until now) to not have any issues. New gensets need to be watched closely until you are sure it is set-up correctly and performing correctly.

I have no idea how your system is wired or if you have the correct xantrex power distribution panels. You would need to post a picture.

The overload of a gen will either trip the gen breaker or cause the xw relay to open under load. Other things also depending on how the charger and AC2 breakers are configured or programmed in. I think I would go back and read this whole thread again.

[I seem to remember that the XW inverters have some capability to draw power from batteries when generator power is inadequate - but that seems unrealistic in this scenario. Irrelevant?]

No not irrelevant, it is a tool that is useful and can keep you from overloading the genset with loads like a pump. It would be better if you let the charger bring the battery up for an hour before you start loads that can wait. Might cost you some fuel. Far cheaper than damaging XW gen input.

I should not tell you this. We have been offgrid without a genset for decades. Impossible in your location but there must be some really nice things about your home. Enjoy it and go outside with an adult beverage and listen to the gen as well as watch the power transfers on SCP. Good Luck!

nkin · December 2020

Excellent. Thanks again Dave.
Sun is low in the sky and often hidden by clouds, so need more than solar.

Nice view - but not high enough for wind - or low enough for hydro.

nkin · December 2020

PS clarification. Our failed generator dates to first work on house about 2003/4. The XW dates to 2009 solar installation - then was replaced under warranty roughly 2012 or so.

XW 4024 - thinking of generator failure

Comments

Categories