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MountainGirl
02-15-2022, 04:56 AM
PO and I recently had the house's panel upgraded - to include a 30amp Inlet so our dual fuel gen could power some of the circuits during outages etc... and I'm wondering - as I'm starting to design the solar system for a new place - if there's such a beast (or if one could be made) that would enable us to also use solar here (on a more limited scale than later)..... sorry this is so convoluted, lemme try again.

What I want is a cord (4prong, 30amp) that would come out of an Inverter - and plug into the new house Inlet. I'm thinking something would have to be made up - and I'm just starting the research on that - but if any of you spark-heads have starting thoughts for me it would be very much appreciated!

Thanks in advance :)

Slippy
02-15-2022, 06:38 AM
Give these knuckleheads a call;
https://backwoodssolar.com


PO and I recently had the house's panel upgraded - to include a 30amp Inlet so our dual fuel gen could power some of the circuits during outages etc... and I'm wondering - as I'm starting to design the solar system for a new place - if there's such a beast (or if one could be made) that would enable us to also use solar here (on a more limited scale than later)..... sorry this is so convoluted, lemme try again.

What I want is a cord (4prong, 30amp) that would come out of an Inverter - and plug into the new house Inlet. I'm thinking something would have to be made up - and I'm just starting the research on that - but if any of you spark-heads have starting thoughts for me it would be very much appreciated!

Thanks in advance :)

Prepared One
02-15-2022, 06:56 AM
Give these knuckleheads a call;
https://backwoodssolar.com

Thank you sir.

Inor
02-15-2022, 06:57 AM
The cable would be easy enough to make but can you guarantee the juice coming from the inverter is only ever going to be a max of 30A?

SOCOM42
02-15-2022, 08:06 AM
My input wiring from my primary genset is 50 amp, I would do the same if I were you.

The increased cost is minimal for 30 to 50, less chance of cooking the cable.

I do back feed through a welding socket which is 50 amp, only had to make up a cable to match the genset.

I never even get near the 30 amp load either, just want to be safe.

Clamp on meter showed a max of about 25 amps when tested, and that was inrush current.

As shown in a previous post, 50 amp socket and plug with a 15 amp plug for reference.

That socket is power for a 250 amp MIG welder in front of it.

Oh, I did in this process bypass the 600 amp main panel.

I have created a checklist of each step to bring the genset on line

and then offline for my daughter to follow for when I am incapable or I am gone.

18022

18023

Your 4 prong twist lock will work fine with this 3 prong 50 amp.

There are only two hot leads in the 4 prong, the two others are a ground and a neutral return.

The last two as in my case can be tied together with no problem.

The cable wire I used IIRC, #8 SO and #8 SOT. Last is for a short jumper.

The product of your intention is easy enough to do, no related to the solar at all unless you intend

to use the genset to also charge the batteries, that is a whole other world.

I have only used the big 3 phase genset once in 20 years, has more test time than work time.

MountainGirl
02-15-2022, 08:40 AM
Give these knuckleheads a call;
https://backwoodssolar.com

LOLOL!!
These folks are just north of Sandpoint ID - and who I bought all the components from for both systems on Peaceful Mountain! They are awesome folks and spent a lot of time answering my questions! Soon as I figure out which way I wanna go - I'll be contacting them to see if they ship to Texas.
If not - a road trip for us might be in order, lol. :impala:

Update: I called, they do. :thumb:

MountainGirl
02-15-2022, 09:08 AM
The cable would be easy enough to make but can you guarantee the juice coming from the inverter is only ever going to be a max of 30A?

At this point in the idea stage - Pretty much.

There'll be no heavy tools or start-up draw... and as long as the Inverter doesn't 'push' more than is asked for, it shouldn't come close to 30.
On the mountain - I knew what could be run at the same time and what couldn't, but what I'm designing for here is a bit different (no on welders - yes on AC units, lol) and I'm still gathering demand numbers.

Goal is to design a system big enough for our needs (wherever we end up) yet could power the few circuits we'd use while still here. Easy to size big; easy to size small; I'm trying to figure out how to use 'big' in a temporary 'small' location. Practical thing would be to wait till we're on our new place - but PO is really impatient; he wants everything RIGHT NOW! ( Just kidding, that's me. :) ) I don't need everything 'right now' - but it might not be a bad idea to have the components in hand... while a person can still actually get them. If you know what I mean.

MountainGirl
02-15-2022, 09:26 AM
My input wiring from my primary genset is 50 amp, I would do the same if I were you.

The increased cost is minimal for 30 to 50, less chance of cooking the cable.

I do back feed through a welding socket which is 50 amp, only had to make up a cable to match the genset.

I never even get near the 30 amp load either, just want to be safe.

Clamp on meter showed a max of about 25 amps when tested, and that was inrush current.

As shown in a previous post, 50 amp socket and plug with a 15 amp plug for reference.

That socket is power for a 250 amp MIG welder in front of it.

Oh, I did in this process bypass the 600 amp main panel.

I have created a checklist of each step to bring the genset on line

and then offline for my daughter to follow for when I am incapable or I am gone.

18022

18023

Your 4 prong twist lock will work fine with this 3 prong 50 amp.

There are only two hot leads in the 4 prong, the two others are a ground and a neutral return.

The last two as in my case can be tied together with no problem.

The cable wire I used IIRC, #8 SO and #8 SOT. Last is for a short jumper.

The product of your intention is easy enough to do, no related to the solar at all unless you intend

to use the genset to also charge the batteries, that is a whole other world.

I have only used the big 3 phase genset once in 20 years, has more test time than work time.

We talked about upping to a 50 amp before having the Inlet installed - but our power needs are relatively small compared to you guys, and PO already has a nice gen so we decided to just stay with 30 amp. AND - After we get outta here, the Solar will be the primary backup; the gen will be used as backup out there until the solar is in place; and then used to keep the batteries topped up, as needed, and the 30 amp I had on the mountain did just fine for that honkin system. Here's a pic of PO's gen:

18024

MountainGirl
02-15-2022, 09:40 AM
Just noticed this -




...

The product of your intention is easy enough to do, no related to the solar at all unless you intend

to use the genset to also charge the batteries, that is a whole other world.

...

Yes, that would be the other use, and is what I haven't wrapped my head around yet.

Mad Trapper
02-15-2022, 10:14 AM
Just noticed this -



Yes, that would be the other use, and is what I haven't wrapped my head around yet.

If you tie into grid with the solar, excess will make your meter spin backwards.

A good battery bank will get you power when sun ain't shining, and be grid independent. Bats will be expensive and you'll want a shed to house them/electronics/wiring in.

Not sure how the option of grid tie in, along with having a batt bank plays out. I'm sure others here can help with information on that.

SOCOM42
02-15-2022, 10:17 AM
A 50 amp system is not much more money, a few bucks only.

The unshown advantage is the larger current capacity, and less resistance in the wiring.

In rush currents can cause an overload like if a fridge and a oil burner come on at the same time.

Also, you had better figure in a well pump if you have not already have.

I have always opted for the next level of capacity, never regretted it either.

MountainGirl
02-15-2022, 10:32 AM
If you tie into grid with the solar, excess will make your meter spin backwards.

A good battery bank will get you power when sun ain't shining, and be grid independent. Bats will be expensive and you'll want a shed to house them/electronics/wiring in.

Not sure how the option of grid tie in, along with having a batt bank plays out. I'm sure others here can help with information on that.

Thanks, MT :)
Not tying into the grid, ever. I'm strongly considering LiFePo4 for the batts (not Lithium Ion);
the next time I buy a lead-acid battery will be never, lol.
Everything will be well protected - it's really nice to not worry about months of freezing temps.

MountainGirl
02-15-2022, 10:43 AM
A 50 amp system is not much more money, a few bucks only.

The unshown advantage is the larger current capacity, and less resistance in the wiring.

In rush currents can cause an overload like if a fridge and a oil burner come on at the same time.

Also, you had better figure in a well pump if you have not already have.

I have always opted for the next level of capacity, never regretted it either.

Agree. The mountain system was intentionally overbuilt so there was never a huge strain on it and I kept the batts topped above 85%. The biggest hog was the well pump... I know what a whole house needs; and would like to set it up here - and I'll likely buy the components before we move - I just dont want to do some things twice (small inverter for here, big inverter there) so I'm thinking a big inverter now... so if anything we can just add more panels after we move. Or, I'll keep them stacked up in the garage. If PO didn't already have the 30 we might have gone 50... but there's other things that need buying, and this was already on hand. I'm just glad we have something for backup here. Who knows what's coming. I never thought I'd be doing this again. :)

Mad Trapper
02-15-2022, 02:11 PM
Thanks, MT :)
Not tying into the grid, ever. I'm strongly considering LiFePo4 for the batts (not Lithium Ion);
the next time I buy a lead-acid battery will be never, lol.
Everything will be well protected - it's really nice to not worry about months of freezing temps.

MG, the grid tie in was just a suggestion to use excess solar when batts are fully charged.

Inor
02-15-2022, 02:40 PM
Thanks, MT :)
Not tying into the grid, ever. I'm strongly considering LiFePo4 for the batts (not Lithium Ion);
the next time I buy a lead-acid battery will be never, lol.
Everything will be well protected - it's really nice to not worry about months of freezing temps.

I helped a neighbor out assembling a pretty good sized solar system with LiFePo4 batteries. He had 64 cells at 275AH each. Those are AWESOME batteries, but... They are expensive to buy and a SERIOUS pain in the ass to get balanced. We tried to top-balance them 3 times (unsuccessfully). We finally had to drain each cell down individually to about 15%, then we made bars from copper tubing and wired them in parallel and let them sit for a week. Finally, we were able to bottom-balance them and do a real slow charge (from the grid at my place) to about 80%. The whole process took almost 2 weeks to get it right. Also getting the charge controller to recognize them as not standard lithium-ion was a bugger. (If you get them configured wrong or not balanced well, they overheat quick.)

I would go with them in a heartbeat, but be sure to allocate enough time to fiddle with them a lot before you actually NEED them.

Dwight55
02-15-2022, 02:53 PM
PO and I recently had the house's panel upgraded - to include a 30amp Inlet so our dual fuel gen could power some of the circuits during outages etc... and I'm wondering - as I'm starting to design the solar system for a new place - if there's such a beast (or if one could be made) that would enable us to also use solar here (on a more limited scale than later)..... sorry this is so convoluted, lemme try again.

What I want is a cord (4prong, 30amp) that would come out of an Inverter - and plug into the new house Inlet. I'm thinking something would have to be made up - and I'm just starting the research on that - but if any of you spark-heads have starting thoughts for me it would be very much appreciated!

Thanks in advance :)

No matter what else you do . . . one thing you MUST do . . . make sure with some kind of dead man switch or something . . . that you cannot have two power supplies going on at once. It is a sure way to get something burned down or fired up. And if you inadvertently do . . . and a lineman out there gets into your hot electricity . . . you will be in SOME KIND OF trouble.

I have mine on a double circuit breaker . . . when you move the handle . . . it turns the fist one off . . . before it turns the second one on.

People who do not think of or plan for that problem . . . generally wind up REALLY wishing they did.

May God bless,
Dwight

MountainGirl
02-15-2022, 03:09 PM
MG, the grid tie in was just a suggestion to use excess solar when batts are fully charged.

Ah - right!
After I saw how much 'excess solar' the panels were sending down on the mountain - the hot water tank got switched from propane to a 20gal 110 electric. That was pretty sweet. :)

MountainGirl
02-15-2022, 03:30 PM
I helped a neighbor out assembling a pretty good sized solar system with LiFePo4 batteries. He had 64 cells at 275AH each. Those are AWESOME batteries, but... They are expensive to buy and a SERIOUS pain in the ass to get balanced. We tried to top-balance them 3 times (unsuccessfully). We finally had to drain each cell down individually to about 15%, then we made bars from copper tubing and wired them in parallel and let them sit for a week. Finally, we were able to bottom-balance them and do a real slow charge (from the grid at my place) to about 80%. The whole process took almost 2 weeks to get it right. Also getting the charge controller to recognize them as not standard lithium-ion was a bugger. (If you get them configured wrong or not balanced well, they overheat quick.)

I would go with them in a heartbeat, but be sure to allocate enough time to fiddle with them a lot before you actually NEED them.
Thanks, they are expensive for sure. 64 cells @ 275AH each you say? Yeah, that would be a good sized system, lol.
Do you recall the manufacturer? What system voltage did he configure? 96? 192?
They make charge controllers specifically for the lithium-iron; maybe one of those would have helped.

MountainGirl
02-15-2022, 03:35 PM
No matter what else you do . . . one thing you MUST do . . . make sure with some kind of dead man switch or something . . . that you cannot have two power supplies going on at once. It is a sure way to get something burned down or fired up. And if you inadvertently do . . . and a lineman out there gets into your hot electricity . . . you will be in SOME KIND OF trouble.

I have mine on a double circuit breaker . . . when you move the handle . . . it turns the fist one off . . . before it turns the second one on.

People who do not think of or plan for that problem . . . generally wind up REALLY wishing they did.

May God bless,
Dwight

Thanks, and yes, absolutely. :)

We had an electrician wire up the panel; along with the 30amp Inlet he added an Interlock up on the Main so it's definitely a case of 'either/or'. Two power supplies at the same time is physically impossible and that's a good thing, too.

Middle of a hurricane is no time to wonder if you really did switch something off. :halo:

Dwight55
02-15-2022, 04:09 PM
Thanks, and yes, absolutely. :)

We had an electrician wire up the panel; along with the 30amp Inlet he added an Interlock up on the Main so it's definitely a case of 'either/or'. Two power supplies at the same time is physically impossible and that's a good thing, too.

Middle of a hurricane is no time to wonder if you really did switch something off. :halo:

Middle of a hurricane is a real good time to get on your cell phone . . . call a realtor . . . find another place to live . . . where they don't have them things.

I rode out a 4 day typhoon . . . (that's what they call em in the far east . . . instead of hurricanes) . . . on a 50 ft wide steel hulled Navy destroyer . . .

All can have them storms that want em . . . I would only live where they could happen . . . if I had an alternate safe space to go to when one comes in.

AND . . . had time to grab my stuff before it hit my place. I probably got too much stuff to put up with them things.

May God bless,
Dwight

Sparkyprep
02-15-2022, 04:36 PM
Middle of a hurricane is a real good time to get on your cell phone . . . call a realtor . . . find another place to live . . . where they don't have them things.

I rode out a 4 day typhoon . . . (that's what they call em in the far east . . . instead of hurricanes) . . . on a 50 ft wide steel hulled Navy destroyer . . .

All can have them storms that want em . . . I would only live where they could happen . . . if I had an alternate safe space to go to when one comes in.

AND . . . had time to grab my stuff before it hit my place. I probably got too much stuff to put up with them things.

May God bless,
Dwight

Pussy. :biglaugh::biglaugh::mocking:

Slippy
02-15-2022, 05:47 PM
Small world, they walked me thru some stuff a number of years ago and were extremely knowledgeable!


LOLOL!!
These folks are just north of Sandpoint ID - and who I bought all the components from for both systems on Peaceful Mountain! They are awesome folks and spent a lot of time answering my questions! Soon as I figure out which way I wanna go - I'll be contacting them to see if they ship to Texas.
If not - a road trip for us might be in order, lol. :impala:

Update: I called, they do. :thumb:

Inor
02-15-2022, 10:43 PM
Thanks, they are expensive for sure. 64 cells @ 275AH each you say? Yeah, that would be a good sized system, lol.
Do you recall the manufacturer? What system voltage did he configure? 96? 192?
They make charge controllers specifically for the lithium-iron; maybe one of those would have helped.

They set up a 48V system. I am not sure the brand of the batteries. (Wang's Pretty Good Batteries maybe?) They bought them from Alibaba and the batteries took several months to get here. When I was out on Alibaba looking around, it seemed to me like every brand looked like exactly the same thing with exactly the same specs. I am guessing somewhere in China is a huge factory where they make all the batteries for every brand?

I only got involved in the effort because they wanted me to bring my tractor by and dig the trenches from the solar panels to the shack where all the electronics are and to dig a couple trenches for some LONG AC runs to outside outlets on the far side of their homestead. But, I did get to inject myself in the whole process so I learned a bunch about setting the whole system up.

Slippy
02-16-2022, 04:27 AM
What attachment did you use to dig the trenches?


They set up a 48V system. I am not sure the brand of the batteries. (Wang's Pretty Good Batteries maybe?) They bought them from Alibaba and the batteries took several months to get here. When I was out on Alibaba looking around, it seemed to me like every brand looked like exactly the same thing with exactly the same specs. I am guessing somewhere in China is a huge factory where they make all the batteries for every brand?

I only got involved in the effort because they wanted me to bring my tractor by and dig the trenches from the solar panels to the shack where all the electronics are and to dig a couple trenches for some LONG AC runs to outside outlets on the far side of their homestead. But, I did get to inject myself in the whole process so I learned a bunch about setting the whole system up.

Inor
02-16-2022, 06:43 AM
What attachment did you use to dig the trenches?

Just the bucket. We only went down 3 feet, so on one side I just carved it out to be able to get the front wheels down about an extra foot.