Offgrid Genset Transfer switch

[5030]

Depending on where the line is, there are trade offs between the longer lifetime of overhead wire compared to underground wire, vs the potentially maintenance costs of overhead wire (tree trimming, and pole/insulator inspections) vs lower maintenance costs, but higher costs of underground runs. At the end of the day, I suspect only the utility has the numbers for those trade offs, and new equipment or labor contractors could push things one way or the other.

Around here, capital investment is guaranteed a 10% ROI for utilities, labor just comes as a running cost. Hence the current push to underground wires at billion dollar prices in California. Warped would be a good adjective to use.

All the best,

Peter

Curious as to the expected life of buried electrical cable as all mine (from the generators) as well as between the shop and barns are buried. In fact the buried propane line from my bottles to the shop run in the same trench as the cables.

 

[ponytug]

Curious as to the expected life of buried electrical cable as all mine (from the generators) as well as between the shop and barns are buried. In fact the buried propane line from my bottles to the shop run in the same trench as the cables.

I guess I would ask;

• What exactly did you bury, e.g. cable type, or wire
• who manufactured the cable,
• how deep was the cable buried,
• what is your local soil and water table like,
• did the wire get unrolled during cold weather, and
• how exactly did you do it?

For obvious reasons, utilities use very high grade cable and install it to SOPs that they know work for their area. The general estimates nationally seem to be 40-50 years for utility underground lines, but I would bear in mind that a large percentage of those buried utility lines are under paved roads, where water, ground shifting, burrowing animals are a non-issue. Plus, many of the buried utility services are more than 600V and subject to different regulations compared to residential regulations, and those difference probably affect the longevity. Around here for instance there is a special grade of sand specifically for burying utilities, and protocols for how it is to be applied.

All the best,

Peter

 

[WinterDeere]

Curious as to the expected life of buried electrical cable as all mine (from the generators) as well as between the shop and barns are buried. In fact the buried propane line from my bottles to the shop run in the same trench as the cables.

Just be aware that there's a 24" separation requirement between gas and electric, for reasons that will become obvious to you the first time you need to dig across that trench. So, if putting both in the same trench, you're going to be digging a mighty wide one, to do it safely and legally.

With so many mini-ex's wearing little 12" buckets these days, it might be easier to just dig two parallel trenches, if doing this over today.

I've never looked into whether it's possible to achieve all or part of the required 24" separation using depth, as in vertical versus horizontal separation. Might be worth researching, for cases where it's easier to go deep than wide.

 

[ponytug]

Just be aware that there's a 24" separation requirement between gas and electric, for reasons that will become obvious to you the first time you need to dig across that trench. So, if putting both in the same trench, you're going to be digging a mighty wide one, to do it safely and legally.

With so many mini-ex's wearing little 12" buckets these days, it might be easier to just dig two parallel trenches, if doing this over today.

I've never looked into whether it's possible to achieve all or part of the required 24" separation using depth, as in vertical versus horizontal separation. Might be worth researching, for cases where it's easier to go deep than wide.

Is that a national standard? I thought that the NEC was silent on that one, but I'm not an expert. I do think separation is good practice, along with burial in sand, and warning tape in the trench to identify what is below, but I have seen it closer in many places. Do you have a link?

All the best,

Peter

 

[MAX-24-Dean]

Is that a national standard? I thought that the NEC was silent on that one, but I'm not an expert. I do think separation is good practice, along with burial in sand, and warning tape in the trench to identify what is below, but I have seen it closer in many places. Do you have a link?

All the best,

Peter

When we installed 4"HDPE NG lines the specification (standard) as provided by Southwest Gas in Arizona was a 12" horizontal seperation and a 12" vertical seperation. Or 24" horizontal seperation. That was 18 years ago.
Shading material in the trench was required to be 3/8" minus and make 90% compaction.
Low pressure lines can be installed in a joint utlity trench, with other utilities. Except for water and sewer. Due to flooding if water or sewer line break. EDIT: washout can cause the Gas line to become unsupported and could cause a leak when the pipe breaks.

There is a different seperation requirement for higher pressure lines that require more distance of seperation.

NFPA 54 applies to Gas lines under 125 psi.

 

[MAX-24-Dean]

Kind of curious about the FNDC in your system since my understanding is that a BMS (Battery Managment System) controls the charge state of the Simpli-Phi batteries. Correct me if I'm wrong here.
Does the FNDC function the same for the Simpli-Phi batteries as it would for lead acid batteries?
Have you had any problems setting up the Simpli-Phi batteries? And how do you like them?
Looking at them for my next set.

 

[WinterDeere]

Is that a national standard? I thought that the NEC was silent on that one, but I'm not an expert.

Good question, and I'm not sure. It's something that's been repeated to me many times, by the township inspector, by our gas company, and even by an excavator we had on-site two years ago. So, whether or not it's a code requirement, it seems to be the ubiquitously-accepted convention, at least around here.

I do think separation is good practice, along with burial in sand, and warning tape in the trench to identify what is below, but I have seen it closer in many places.

Yeah, I can't stand folks who bury utilities, and don't take the extra two minutes to lay some warning tape when back-filling. I spent most of the summer of 2023 digging utilities in our back yard, as part of a pool and patio expansion involving a lot of electric, plumbing, and low-volt wiring, and cursed every prior contractor who ever worked on this property, in the process.

Do you have a link?

I was actually repeating from memory, but going to Google and entering "buried gas electric separation" turned up several links repeating this 24 inch separation recommendation or requirement. Here's the first of a bunch:

Typical Trench Detail – Lane Electric Cooperative

laneelectric.com

 

[JRH02]

Kind of curious about the FNDC in your system since my understanding is that a BMS (Battery Managment System) controls the charge state of the Simpli-Phi batteries. Correct me if I'm wrong here.
Does the FNDC function the same for the Simpli-Phi batteries as it would for lead acid batteries?
Have you had any problems setting up the Simpli-Phi batteries? And how do you like them?
Looking at them for my next set.

@sodamo

 

[sodamo]

Sorry, I got behind.

Only cursory consideration of going underground back when we started but was told it would be even more expensive so I disregarded. 20 years of hind sight and maybe I should have considered a bit more. During that time I ran about 350ft of underground service from house to our cottage.
Back initially I didn’t even consider to ask if I could doing any of it, like the trenching, myself.
But reality, I still would have eventually added solar and likely a less robust system, so I’m currently happy.

 

[sodamo]

When we installed 4"HDPE NG lines the specification (standard) as provided by Southwest Gas in Arizona was a 12" horizontal seperation and a 12" vertical seperation. Or 24" horizontal seperation. That was 18 years ago.
Shading material in the trench was required to be 3/8" minus and make 90% compaction.
Low pressure lines can be installed in a joint utlity trench, with other utilities. Except for water and sewer. Due to flooding if water or sewer line break. EDIT: washout can cause the Gas line to become unsupported and could cause a leak when the pipe breaks.

There is a different seperation requirement for higher pressure lines that require more distance of seperation.

NFPA 54 applies to Gas lines under 125 psi.

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Kind of curious about the FNDC in your system since my understanding is that a BMS (Battery Managment System) controls the charge state of the Simpli-Phi batteries. Correct me if I'm wrong here.
Does the FNDC function the same for the Simpli-Phi batteries as it would for lead acid batteries?
Have you had any problems setting up the Simpli-Phi batteries? And how do you like them?
Looking at them for my next set.

FNDC has basically same shortcoming - SOC drifts. I’ve not had any issues who died and I do like my SimpliPhis. Set up very easy. All same length to a Midnight combiner with breakers. Mkes it easy to turn off when needed, also easy to add my secondary charging generator.
I am gentle with than preferring not to go under 30%