Backup Generator Wiring

I stabilized our entire grid by dropping a few grand on a generac. Used to lose power relatively often for hour or two. Since I installed that badboy. Haven’t needed it to kick on for more then 10 min once in about 4 years.
 
benyflyguy said:
I stabilized our entire grid by dropping a few grand on a generac. Used to lose power relatively often for hour or two. Since I installed that badboy. Haven’t needed it to kick on for more then 10 min once in about 4 years.
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Same. The co-op here will come out and put in a transfer switch for free, so I bought a generator and got set up. The power hasn’t been out once in 8 years.
 
Jim Rosenow said:
You do nice work, Rich!

A parallel question for you master electricians, if Rich will permit the digression....

Our house was wired for a generator when we built it.... transfer switch/lock-out, etc with a lead to a 4-prong 220 box on the outside wall like Rich has. Works great with our 10kw gen. I got inquisitive the other day with all the storms, and realized that running the 10kw for 24 hours will burn a BUNCH of gas (we have no natural gas or LP tank).

So...I came up with plan B. A little Honda 2kw gen will run most of the stuff we need most of the time (all LED lights, one fridge, one freezer), and just sip fuel. Was thinking of getting one of those and only running the big gen when more power is needed for a short period (cooking, heating water, etc), in a prolonged outage.

The problem is getting juice from the 110 plugs in the little gen thru the 4-prong receptacle on the outside wall to the breaker box (after turning off all the 220 stuff in the breaker box of course). I suspect there's no commercially-available cable for this, as it's somewhat unique to our situation. I resist the double-ended male plug cord to a 110 outlet 'solution', although I hear that works, if you turn off the main breaker first.

Thoughts? Thanks!

Jim
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I just looked up a digital version of the spec sheet for the generator I bought to check on the fuel consumption. It has a seven-gallon tank and will run nine hours at half-load or seven hours at full load.

http://rsprdigital.com/aipower/spec...r_12VDC_Outlet_2018_spec_sheet.compressed.pdf

So it burns about 0.8 GPH at half load, or about 1 GPH at full load. I don't think that's too horrible. It translates into about 20 gallons of gas / 24 hours running at half-load most of the time with occasional higher loads. So 40 to 45 gallons -- eight cans -- should get me through two days. Outages longer than that are unusual here (but do happen from time to time).

I presently store 20 - 25 gallons of gasoline at any given time for the power equipment and other contingencies, so I suppose I need to add three gas cans to be good for two days. That's more gasoline than I'd care to store given the choice. But it's still better than sitting in the dark freezing my ass off like I did last winter when the power went out.

There's also a third-party modification to enable the generator to run on propane or natural gas (as well as gasoline), presumably with reduced output due to the lower energy density of those fuels (and likely violating the warranty). I'll consider that doohickey once the warranty expires (or sooner if the manufacturer comes out with an "official" version). I'd probably go with gasoline first for the higher output with the option to switch over to propane if need be during an extended outage. I already have propane for the heat, so I could tap off that supply with a regulator.

Rich
 
Greg Bockelman said:
ALUMINUM cable?!? I didn’t know you could get that crap anymore.
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Almost all larger sized cable is aluminum. There's NOTHING whatsoever wrong with Aluminum wiring provided you do it right. The problem came with using aluminum branch circuit wiring with connectors and devices that weren't designed for aluminum (as you may know from your airplane construction, aluminum forms a protective oxide very quickly, which also has much higher resistance than the metal.
 
RJM62 said:
option to switch over to propane if need be during an extended outage.
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Becareful on using propane. I've several gensets slightly larger than yours suck down a 120lb tank in no time at all.
 
I have a propane fueled 20kw Generac with auto start and transfer.

It burns 1.8 gallons of propane an hour under full load. The 500 gallon tank affords us 10 plus days of power.

I heat with propane and heat water with propane as well.

Kudos to the guy I bought this house from...
 
Kelvin said:
I have a propane fueled 20kw Generac with auto start and transfer.

It burns 1.8 gallons of propane an hour under full load. The 500 gallon tank affords us 10 plus days of power.

I heat with propane and heat water with propane as well.

Kudos to the guy I bought this house from...
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That sounds very similar to our setup. 500 gallon propane tank, 20 kW Generac with auto start and transfer. All put in by the people who built the house.

We don't heat with propane or heat water with propane, but our Wolf 6-burner double oven range uses propane. We added that so we ran the line for it, previously the tank was used strictly for the generator.

Heat is a heat pump, I'd rather use propane. Maybe when this heater goes out (hopefully not for a while).
 
flyingron said:
Almost all larger sized cable is aluminum. There's NOTHING whatsoever wrong with Aluminum wiring provided you do it right. The problem came with using aluminum branch circuit wiring with connectors and devices that weren't designed for aluminum (as you may know from your airplane construction, aluminum forms a protective oxide very quickly, which also has much higher resistance than the metal.
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I've seen lots of larger cable be made from aluminum. Didn't realize it was "almost all", but given the cost vs. copper that makes sense. I can't remember what they were running for the service to the house, didn't look closely enough.

Either way, it was the right price and did the job. Running it through the conduit (and especially through the wall) was not fun, but it's all hooked up and working now. Very satisfying to have no shortage of outlets in the garage now.
 
Nice set-up, Ted!

What I'd really, really like to do is buy a diesel-powered generator. I'm sitting on my couch looking out the window at a source of un-limited diesel (sumped jet-A) that I have a key to, with 20k gallons in reserve, if push really comes to shove some day. I balk at $4k for Generac's only (5kw) model, and have been unsuccessful as of yet finding something else I would trust for a longer-term outage (anyone heard of Duromax generators for example?). Any leads on a decent-priced 10kw or so diesel unit? 10kw is plenty, as we mostly heat with wood, so we just need to keep lights and refrigeration going.

A Craigslist search shows only one used 500 gallon LP tank fairly local for $750.... as much as the mini-gen, out the gate (if I wanted to modify my current gen for LP). Then you have to fill it :)

Jim
 
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Jim, keep in mind that Jet A and diesel aren't entirely equal. Jet A doesn't have the lubricity of diesel. Yeah, you can run diesels on Jet A, but you can run diesels on gasoline for a period of time as well before things go bad. On the aircraft diesel engines they've had to use different fuel pumps especially to handle the specifics of Jet A as opposed to diesel. Plus as everyone else has stated, once you get a generator you pretty much never need it. Propane is the best in my opinion because it doesn't go bad.
 
I’ve had a Northern Lights 6KW diesel genny for about 15 years. Mine’s for primary power at the cabin but they’re used as home back-up units, too. Hands down the best diesel gensets I’ve been around. Not portable, though. My home backup is a Honda and lives in the garage. I wheel it out and plug it in when needed. Simple and clean. A diesel unit needs a dedicated space and after a year or two the area will smell like diesel. Consider a separate gen shed if you go diesel. Mine burns #1 stove oil because that’s what I transport in. Winter, summer, not a problem.
 
Thanks, Ted....I learned something this morning.....lubricity....I love it! Early in the day for me, too :) Completely agree on never needing a gen after you have one. Our current one has worked that way for 7 years.

Does diesel go bad?...not a rhetorical question....I didn't know so, but don't know not. They put an anti-fugicide in our jet-a to prolong life, but it's constantly cycling thru the storage tanks, anyway.

Frankly, my concern is our aging electrical infrastructure and vulnerabilities to sabotage may make power outages more common as we go along, so trying to stay ahead of the curve.

Jim
 
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I use mine 2-3 times a year. Sometimes less. And with that, a pirep I’ve learned along the way. Maintain your starting batteries or you may be sad on that night when you have a back-up power system that won’t start.
 
Jim Rosenow said:
Nice set-up, Ted!

What I'd really, really like to do is buy a diesel-powered generator. I'm sitting on my couch looking out the window at a source of un-limited diesel (sumped jet-A) that I have a key to, with 20k gallons in reserve, if push really comes to shove some day. I balk at $4k for Generac's only (5kw) model, and have been unsuccessful as of yet finding something else I would trust for a longer-term outage (anyone heard of Duromax generators for example?). Any leads on a decent-priced 10kw or so diesel unit? 10kw is plenty, as we mostly heat with wood, so we just need to keep lights and refrigeration going.

A Craigslist search shows only one used 500 gallon LP tank fairly local for $750.... as much as the mini-gen, out the gate (if I wanted to modify my current gen for LP). Then you have to fill it :)

Jim
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Getting it inspected first wouldn't be a bad idea, either.

Rich
 
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Stewartb said:
I’ve had a Northern Lights 6KW diesel genny for about 15 years. Mine’s for primary power at the cabin but they’re used as home back-up units, too. Hands down the best diesel gensets I’ve been around. Not portable, though. My home backup is a Honda and lives in the garage. I wheel it out and plug it in when needed. Simple and clean. A diesel unit needs a dedicated space and after a year or two the area will smell like diesel. Consider a separate gen shed if you go diesel. Mine burns #1 stove oil because that’s what I transport in. Winter, summer, not a problem.
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That's one serious unit....love that it's 1800 rpm, and also variable rpm! Will look into that more. Don't care that it's not portable and smells like diesel...would sit in an un-attached second garage along with the wood supply. (If we're gonna have a fire, might as well make it impressive! :)

Also will be looking at the capability of the current gennie to be converted to gas/LP both. Two options for power are a GOOD thing, and LP is a good choice.

This truly is an amazing place to throw questions out and let the answers fly....thanks all!

Apologies for total thread drift, Rich!

Jim
 
Jim, I don't think letting diesel sit for extended periods is good. That said my D4 has some diesel that is very old and it's still running.
 
Add a water separating fuel filter and don’t worry about it. My generator’s fuel tank is a 30 gallon clear poly drum. Never any fuel quality issues.
 
Bell206 said:
Becareful on using propane. I've several gensets slightly larger than yours suck down a 120lb tank in no time at all.
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I have a thousand gallon tank feeding mine. Still even running constantly for several days doesn't seem to put much of a dent in it (and I've got an 80KVA generator).
 
I had a tank full of probably 8 year old diesel on my sailboat.. Ran the engine fine..
 
Jim Rosenow said:
That's one serious unit....love that it's 1800 rpm, and also variable rpm! Will look into that more. Don't care that it's not portable and smells like diesel...would sit in an un-attached second garage along with the wood supply. (If we're gonna have a fire, might as well make it impressive! :)

Also will be looking at the capability of the current gennie to be converted to gas/LP both. Two options for power are a GOOD thing, and LP is a good choice.

This truly is an amazing place to throw questions out and let the answers fly....thanks all!

Apologies for total thread drift, Rich!

Jim
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No drift that I can detect. Generators is generators.

Rich
 
Ted DuPuis said:
I've seen lots of larger cable be made from aluminum. Didn't realize it was "almost all", but given the cost vs. copper that makes sense. I can't remember what they were running for the service to the house, didn't look closely enough.

Either way, it was the right price and did the job. Running it through the conduit (and especially through the wall) was not fun, but it's all hooked up and working now. Very satisfying to have no shortage of outlets in the garage now.
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When I worked in the industry house feeds were aluminum. much lighter and easier to work with. The big underground stuff we put in was aluminum also, at least the direct buried stuff. Manhole to manhole stuff was copper. The most fun was sodium cable. :D
 
Jim Rosenow said:
Probably the easy way is just run a 110 extension cord to inside the house from a little gen, and split off from there to power what I want. Not as elegant, but It will, after all, be in an 'emergency' situation.
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That's what I do for hurricane outages. So far, so good. Fridges, fans, cell phones, lights. Good enough.

Now, you poor northerners who are looking at cold weather survival after the polar vortex freezes the dogs to the fire hydrant, maybe it would be not so much help.
 
For those of you that have a home backup generator that has the Evolution or Nexus controller (not just Generac) and you want some monitoring without paying for the manufacturer's wireless box/service check this out: https://github.com/jgyates/genmon
Pretty slick little setup w/ a Raspberry Pi. A little more involved than buying a Stratux setup from someone online but not too bad to cobble the hardware together. Someone offered to do some of the hardware legwork and is selling them on eBay but you can cobble it together for way less.
Hell, there's even a propane tank level monitoring solution: https://www.tankutility.com/
 
Well, y'all made me go get a generator now, should be just enough to run the refrigerator, septic tank and internet, I was going just going to put an inlet on the outside of the house and a couple outlets inside I can run extension cords from. Then I realized if I go through that trouble I should do it right, so a proper inlet and interlock was ordered, now need to go find some #6 locally, then I'll be set for future expansion.
 
chartbundle said:
Well, y'all made me go get a generator now, should be just enough to run the refrigerator, septic tank and internet, I was going just going to put an inlet on the outside of the house and a couple outlets inside I can run extension cords from. Then I realized if I go through that trouble I should do it right, so a proper inlet and interlock was ordered, now need to go find some #6 locally, then I'll be set for future expansion.
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If you can't find it locally, Amazon sells both NM 6/3 and THWN. They also sell a NEMA 14-50 box bundled with a 50A cord at a decent price. The box is a bit tight and the ground lug is too small for the included 6-gauge ground wire, but otherwise does the job well enough. After several failed attempts to make the ground wire stay put, I ditched that wire in favor of 10-gauge THWN (perfectly legal here). The cord is fine.

Lowes carries all the wire needed in-store around here, and they may be cheaper if you don't need much of it because they sell by-the-foot. You'll need the NM 6/3 w/ground for the interior work, and THWN for anything that will be outdoors, even if it's in conduit. Lowes also stocks all the conduit and doodads in-store around here, but not a 14-50r (50A) inlet box or cord. (They can ship those parts, though).

Rich
 
RJM62 said:
Lowes carries all the wire needed in-store around here, and they may be cheaper if you don't need much of it because they sell by-the-foot. You'll need the NM 6/3 w/ground for the interior work, and THWN for anything that will be outdoors, even if it's in conduit. Lowes also stocks all the conduit and doodads in-store around here, but not a 14-50r (50A) inlet box or cord. (They can ship those parts, though).
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I ordered what looks like a decent 50 amp locking inlet with an in-use style cover from Home Depot along with the matching cord receptacle and interlock for my panel. The in-use cover since it rains about 370 days/year here, and I always prefer locking plugs. I sort of have 2 options for placement. On the porch out of the weather and then can use the generator there or with a longer cord in the yard, or the inlet on the edge of the deck but that adds conduit/etc and puts the box always in the weather. I'm leaning towards the porch so if I want to switch it later I'll have enough NM in the crawl space to pull back to a junction box to run the conduit out, or if I want I can make a little generator doghouse a few feet farther and bury a conduit run to it.

We're now up to 4 non-big-box hardware stores, so I joke I have to remember which of the 4 have what I want, and I have no idea which of them carry #6 of any flavor, luckily I'm going to the big city on Saturday so I'll just grab it then.

20180926_095724.jpg
The porch location is next to the wheelbarrow, and the deck location would be at the left side. The main panel is on the other side of the wall from the meter so either run is still pretty short. Obviously this was taken during one of our brief 5 minutes of sun before the rain starts again. (I'm trying to encourage the tourists to never come here...)
 
Lubricity, baby!!!.....don't know why, but the word has struck a cord with me. :)

After Ted gave me the heads-up on the difference in lubricity between diesel and jet-a being an issue for use in generators, I did some more research, and he was (not to be surprised), completely correct. If you want something that will put you to sleep..... http://www.dtic.mil/dtic/tr/fulltext/u2/a326098.pdf. Pity they don't mention branding of the products.

Just stopped by and had a talk with the DOM for the jets, who also confirmed the issue. Upside....they use jet-a in the fuel truck and a couple other vehicles, so all the jet-a has a specific lubricity additive to ameliorate the problem, in addition to an algicide to keep tanks clean. One of the local pilots is a retired OSU chemistry prof, who researched the additive, and uses the jet-a in his tractor with the additive.

Now I've gone full circle, and again considering an upgrade to a diesel generator, from the current gas gen. As Roseanne Rosannnadanna said, "It's ALWAYS somethin'!!".

Jim
 
Back in PA they used sumped Jet-A in the fuel trucks as well, and put that additive in. By the way, both of those trucks ran like crap, but they were also modernish common rail direct injection engines that were unhappy with all the idling and short runs to start.

Like I said, I wouldn't do it myself, but I'm probably overly paranoid about that stuff since I used to run these things on dynos. :)
 
I suppose a mixture of jet-a and diesel would afford even more protection.....just thinkin' out loud.

Jim
 
Yup.....as long as diesel is available......it's an 'emergency' generator :)

Jim
 
My general thought is that I'd keep diesel in it as the norm. If you're talking about an apocalypse generator, that's a different story and you put in whatever you can that's combustible.

Except for alcohol. That we save.
 
Also, Jim, if you're thinking a diesel generator you want to be able to run on anything, you might want to look into a military spec one. My understanding (although someone who knows more than me about this stuff can comment) is that the military spec diesel equipment is designed to be able to run on JP-whatever and is built with components that can take whatever you throw in it. Doing a quick search on eBay the prices seem competitive on the used equipment too.
 
Ted DuPuis said:
Jim, I don't think letting diesel sit for extended periods is good. That said my D4 has some diesel that is very old and it's still running.
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You can get diesel fuel polished (and yes, that's the term) periodically.

The big commercial diesel generator users do this before storm season. It's cleaning, filtering, removing water & microbes, and replenishing additives.
 
Tribology, indeed, Rich!!! :) .....and yes, of course I had to look it up!

I like the mil spec idea, Ted! Makes sense...Will do some looking in that genre'.

Interesting about fuel polishing!

Jim
 
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