Back to do again in NC..

ywhic · September 2019

I'm back. Sold property and my 8 panel setup in W Texas a few years back. Left it with 660ah 12vDC batterybank, Midnight Classic and a simple Xantrex SW2000 20 amp inverter for the buyer. I ran the 20 amp inverter to a small breaker box that had like 3 runs of outlets and advise owner that he has 18 amps max to play with..

Anyway was thinking off grid for NC property I'm working on.. same setup..

Which or how would I get a house panel setup to run 240VAC service? Some would be 120vac obviously and maybe 1 line for 240vac.. Is there a recommended inverter that does say 5000w and uses 24vdc (obviously more efficient than 12vdc).. I saw an AIMS brand at 12vdc/5k but it had mixed reviews..

120VAC was easy..

Estragon · September 2019

What's the 240v load?

5kw is on the high side for 24v. You may want to consider 48v. This will keep wiring and related size more reasonable, and 48v essentially doubles the capacity of a given charge controller.

ywhic · September 2019

Estragon said:

What's the 240v load?

5kw is on the high side for 24v. You may want to consider 48v. This will keep wiring and related size more reasonable, and 48v essentially doubles the capacity of a given charge controller.

I would probably just say a 1/2 HP well pump probably on the 240vAC..

I was checking 120vAC pumps and they are conflicts of start AMPS draw vs running. Someone said 64amp start and 12amp running.. but my response to that was 64 amp thru 12AWG even for a burst seemed rediculous considering it says 30 amp breakers for most well pumps.

Estragon · September 2019

I run a 240v submersible pump off a stack of 120v inverters via a 240v autotransformer. It's my only 240v load, so it made more sense to me to run a 120vac system, and use the autoformer for the one periodic 240v load.

By using a 120v master/slave stack, only the master stays "lit", while the slave(s) "sleep" until needed to power loads. Having a big inverter "lit" all the time can be a big daily load by itself. In my case, a 3500w@120v master handles almost all loads. The slave wakes up only if multiple big loads happen at the same time. If there's a problem with one inverter, I can also swap master/slave designations and keep all the lights on.

Using (say) a pair of inverters stacked for 240v (or a single inverter doing the same thing), keeps the stack mostly lit to serve 120v loads on each leg of a 120/240v split phase panel. In addition to the load keeping more inverter lit, there can also be issues balancing 120v legs of a 120/240v panel.

mike95490 · September 2019

here's the pump wattage chart. Franklin makes most of the motors for pumps.

Also, Power Factor, Locked Rotor Amps and Running amps all have impact too.

3 wire motors with the capacitor (control) box above ground, are somewhat "easier" to start.

Image: https://us.v-cdn.net/6024911/uploads/editor/ls/d3jjw97dbwyg.jpg

shawnj72 · September 2019

Most motors are Capable of 300% and some 600% of the rated running currents for a such time usually 5%. It is not un common to have a motor run its peak + currents for the given time. Example we have a 350 HP motor during Start Run the max 600% of its rated current. The wire is rated for 380-430amps respectably. But this motor starts up over 1200 amps Every day for almost a minute. I have a 1HP 2 wire well pump with 12 awg rated at 25 amps respectably, but during startup it can reach 60 but usually only for a split second. It is rated for 11.5 amps and have it on a dual 15a breaker. That's why there are fuses and Breakers. If you exceeded the 5% load for the given time of the breaker it would trip as it should.

ywhic · September 2019

Estragon said:

I run a 240v submersible pump off a stack of 120v inverters via a 240v autotransformer. It's my only 240v load, so it made more sense to me to run a 120vac system, and use the autoformer for the one periodic 240v load.

By using a 120v master/slave stack, only the master stays "lit", while the slave(s) "sleep" until needed to power loads. Having a big inverter "lit" all the time can be a big daily load by itself. In my case, a 3500w@120v master handles almost all loads. The slave wakes up only if multiple big loads happen at the same time. If there's a problem with one inverter, I can also swap master/slave designations and keep all the lights on.

Using (say) a pair of inverters stacked for 240v (or a single inverter doing the same thing), keeps the stack mostly lit to serve 120v loads on each leg of a 120/240v split phase panel. In addition to the load keeping more inverter lit, there can also be issues balancing 120v legs of a 120/240v panel.

Any recommendated brands to do this?? Hard to find stackable..

Estragon · September 2019

I'm happy with my Outbacks (FXs). I think others like Schneider also do parallel stacking. I think Midnite's new one is supposed to do so too, but I don't know when it will be generally available.

ywhic · September 2019

Estragon said:

I'm happy with my Outbacks (FXs). I think others like Schneider also do parallel stacking. I think Midnite's new one is supposed to do so too, but I don't know when it will be generally available.

Trying to keep this economical.. $1800 per unit for the Outback FXR for a 3kw model seems steep..

Anyone know the Schneder models that can do this..

MrM1 · September 2019

The Conext SW and XW+ Series will do this with ease. I use the SW 4024 (3400W continuous / 4000W for 30 min / 7000W for 5 seconds) that is a 24v that is rated for about 4000 watts. I run my 240v 1/2 hp well off the inverter daily. As a grid interactive setup (part grid tied / part off grid selectable on a circuit by circuit basis) I connected the L1 and L2 of the inverter to the Reliance Controls Pro Tran 2 10 circuit transfer circuit box and tied that to my main load panel to select which circuits are off grid and which are grid tied.

ywhic · September 2019

MrM1 said:

The Conext SW and XW+ Series will do this with ease. I use the SW 4024 (3400W continuous / 4000W for 30 min / 7000W for 5 seconds) that is a 24v that is rated for about 4000 watts. I run my 240v 1/2 hp well off the inverter daily. As a grid interactive setup (part grid tied / part off grid selectable on a circuit by circuit basis) I connected the L1 and L2 of the inverter to the Reliance Controls Pro Tran 2 10 circuit transfer circuit box and tied that to my main load panel to select which circuits are off grid and which are grid tied.

So if I get the SW4024 for the $1300 it can do the 120/240 L1/L2 split and if I'm not grid tied just run this into a standard 100 amp panel like regular utility would be.. and toss some 120VAC breakers in for outlets and lights and a single 240VAC breaker in for a well pump and all should be good to go.. and not have to stack..??

Estragon · September 2019

If the inverter does split phase 120/240, you wouldn't need to stack unless you needed more capacity than a single inverter can provide.

I'm not familiar with the SW, but in some split phase applications load balance between 120v legs can be an issue. This can be addressed if need be by putting larger 120v loads on opposite legs, or by stepping the 240v down to 120v with an autoformer.

MrM1 · September 2019

Yes! And What Estragon said - load balancing of Ur 120v loads is a good idea. Ur 240v loads are already balanced. The Conext SW 4024 is a 24v 1700W per leg split phase 3400W 120/240v inverter. U'd need nothing else. Just the inverter and it's System Control Panel. (you really do need an SCP to configure the inverter)

L1 and L2 out from the inverter would connect directly to a 100a load panel ( although the inverter could never Supply 100 amps AC). No stack necessary. As long as your loads (pump etc) do not exceed the values of the inverter for the set time frames in the specs I linked above (3400W continuous / 4000W for 30 min / 7000W for 5 seconds - and not more than 1700W on either leg continuous ) you would be good to go as you described.

No need to stack unless you needed more capacity than the SW series can provide. But if so, I'd probably go with the XW+ series rather than the cost of stacking the SW because there have been some issues (is seem to recall - but not sure) in stacking the SW and not sure if the latest firmware to the SW got those issues ironed out.

ywhic · September 2019

So hypothetically would 430AH of GC2 batteries in 24v configuration with 2 sets of 4 batteries (to get 24vdc each set) work to run this?? All batteries are 6vDC and 215ah rated..

I understand the solar has to produce double the amps basically to keep the batteries fresh daily and not run batteries down below 60 percent or so..

My old setup was 1300w of solar (8*140w panels) into 6 GC2, but that was a 12v setup.. but was 660ah capacity.. and that was with the MN Classic 150 and simple 2K Xantrex and just a swamp cooler at 4 amps and minifridge.. and a couple of lights.. Peak sun in W Texas was yielding 70-80 amps input on that setup for 6-8 hours a day.. always ran really well.

Estragon · September 2019

The "rule of thumb" for an adequate but cost-effective array for full-time off-grid is ~C/10, so something like 45-50a in your case. Real world output at operating temps might be ~75% of panel STC rating, so roughly 60a to get 45a.

Whether 430ah of capacity will work, and whether 60a x 24v = ~1500w array will keep it properly charged depends on loads and location/climate. The design of a system that will meet your needs/expectationd should start with quantifying loads, then designing battery bank to service those loads, then designing charging sources to service that bank.

Starting with a realistic estimate of daily loads is key. A simple spreadsheet listing loads in watts, times hours of use gives daily watt-hours for that load. For example, a fridge might take 200 watts when running, and have a 1/3 duty cycle, so 8 hrs. 200w x 8hrs = 1,600 wh. The sum of all the wh loads gives a daily wh budget. I'd highly recommend not skipping this step.

ywhic · September 2019

The irony is I was leaning towards 48-60amps worth of panels for this system to start. Like 6 panels at 8 amps each or so, about 300w each.

Still haven't checked the azimuth for where I'm at in NC. I just got the GPS coordinates.

I had bought the plug in amp reader from HD for the last setup to get my amps for each item that was planned. Didn't plan on the vacuum at all. So had to stick with a 6-8 amp model instead of the big 10-12 amp models. Also when initially doing TX I did try a 6000BTU AC system but that laughed at me on start up when I only had a 440ah battery bank. And in W TX I was able to be smart and run the swamp cooler as it was very dry. Got it from 110 inside to 74 inside..

MrM1 · September 2019

In N FL I can run a 5000 BTU AC from this system I have off grid. My 5000 BTU AC pulls less than 600 Watts. So with a 435 Ah battery bank, even at night I can run it a few hours (maintaining a slightly higher than comfortable temp) and still have a good bit of SOC (state of charge) left for the much smaller loads thru the night. And in the day, in decent weather, bank is usually charged by noon so running a 600W load all afternoon is not much trouble. (provided I do not do much else - Like heat water)

MrM1 · September 2019

ywhic said:

So hypothetically would 430AH of GC2 batteries in 24v configuration with 2 sets of 4 batteries (to get 24vdc each set) work to run this?? All batteries are 6vDC and 215ah rated..

If I was going to buy 8 GC2 batteries at 215Ah each, I would consider the SW 4048 48v inverter so that I could have all the batteries in series rather than a 4S2P configuration. You will get the same capacity that way: 24v x 430 = 10,320 OR 48v x 215 = 10,320.

This was the one "mistake" I made with my system. I had it in my had, "get the biggest battery you can afford". I could not afford 8 435Ah's but I could afford 4 of them. I got so wrapped up in "get the biggest battery", I totally forgot my math. Had I went with a 48v inverter, I could have gotten 8 220Ah GC batteries, that would have cost less than my 4 435Ah battery bank, I would have had the same capacity ... And I could have added even more panels on my Midnite solar Classic 150 charge controller (which is pretty maxed out in my 3S3P 24v configuration) and had a larger array.

As a side note: The Conext SW 4048 48v inverter has a slightly higher Watt output rating (3800W / 4400W for 30 minutes / 7000W for 5 seconds) than its counterpart SW 4024 24v , but costs basically the same. If you have to have 24v ... I'll sell you mine ... I wanna upgrade ... LoL

Coach Dad · September 2019

ywhic said:

Which or how would I get a house panel setup to run 240VAC service? Some would be 120vac obviously and maybe 1 line for 240vac.. Is there a recommended inverter that does say 5000w and uses 24vdc (obviously more efficient than 12vdc).. I saw an AIMS brand at 12vdc/5k but it had mixed reviews..

120VAC was easy..

The Magnum MS-PAE 4024 will do what you are looking to do, except it is a 4000w not 5000w. I've got mine connected to a house panel with split phase 120/240V for about 7 years now and it works perfectly. I run a 3/4hp 240v well pump with it and of course all the normal 120v items (TV, Refrig, lights etc)..
https://www.magnum-dimensions.com/sites/default/files/spec_tables/pdf/MS-PAE-series_datasheet_64-0275_RevE_web.pdf

ywhic · September 2019

In this pic I see.how they split it 240 on left and 2 x 120 on right.. they used red for one 120 and black for the other 120.

Can I do 2 more breakers for 120 the same.. ie 1 red hot leg, 1 black hot leg?? And is the left side of the panel just 240 or are they just trying to show an easy drawing??

As far as I now most panels have 2 hot legs down the middle of the back.. I never researched how a 240 breaker works or makes the voltage 240 from a single 120 'leg'.. lol

ywhic · September 2019

ywhic said:

In this pic I see.how they split it 240 on left and 2 x 120 on right.. they used red for one 120 and black for the other 120.

Can I do 2 more breakers for 120 the same.. ie 1 red hot leg, 1 black hot leg?? And is the left side of the panel just 240 or are they just trying to show an easy drawing??

As far as I now most panels have 2 hot legs down the middle of the back.. I never researched how a 240 breaker works or makes the voltage 240 from a single 120 'leg'.. lol

Nevermind I'm an idiot.. forgot the wider 240 breakers bridge the gap and grab one 120 leg from each side.. lol

MrM1 · September 2019

Yup... Just wire it like L1 and L2 coming in from grid service on a standard panel. Come in through a "main" breaker that is not 200 amp but rather rated for Ur system set up and wire size.

Back to do again in NC..

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