More backup generator discussion: Backing up well pump in a different structure

[rbstern]

I am a bit of a cheapskate so I have to ask. Aren't you spending an awful lot of money for a two hour outage? For two hours we can rely on bottled water.

Just asking.

RSKY

When Irma came along, we were surprised at how long it took the county and local EMC to get everyone back online. Also, for outages where power is down but phone is up, I can still be connected to the Internet for my work, and sometimes my responsibilities to my clients are urgent enough to bear the expense for backup power.

 

[MossRoad]

Since you have two meters, is it legal to run wiring between the two to run them both off of one generator?

If yes, you could probably run a feed between the two, and use a kirk key setup for lockout of utility power before being able to feed the old house from the new house.

KIRK(R) - The Leader in Trapped Key Interlocks

These were suggested a few years ago by member Aczlan in another generator thread. They seem like a really simple, yet elegant solution.

Put a kirk key in the old house to make it switchable between utility power OR new house power. It can't be fed from both at the same time due to the key. It's an on-off-on arrangement. No possible way to mix feeds.

 

[rbstern]

I like redundicy, I have 2 HVAC system on a house that only needs one. I have 3 generators, 2 freezers, ect.

If I were in this situation, I would install another well for the new house and run a pipe between the houses with necessary valves to feed both houses from either well in the event of a failure.

I would keep them independent and only tie together in an emergency.

Around here, a 4" well with pump and 80 gal tank is around $4500.
Not unreasonable if you are building a new house.

I do understand that wells can be considerably higher depending on geographic location. And this option may not be feasible for everyone.

It would definitely solve your backup power issue though!

Wells around us are typically 200 to 300' deep. Doubt that could get done for $4500. It's a possibility.

 

[rbstern]

I don't understand how a home run wire from the new house to the well will help. Isn't the well pump currently powered through the pressure switch in the old house, at the pressure tank? The new house would need a wire feeding directly to the pressure switch in the old house.

You are correct.

 

[Jcoon]

Don't want to distract too far from OP's question, but is one of your panels sub-fed from the other; this is very different than having 2 meters.
If sub-fed, only the main panel should have ground and neutral bonded with each other. The ground bus should be isolated from the neutral bus (green wires separated from white wires) in the sub-fed panel.

The issue/problem if ground and neutral are bonded in 2 places is the ground and neutral conductors between those 2 places are now essentially parallel conductors connecting the same points: so that the neutral current is split with some running through the (green) ground conductor. The problem with this is ohms law. A current running through a conductor (that has resistance) will create a voltage across that resistance (conductor), this is a problem because everything connected to the (green wire) ground conductors should be at 0 volts (grounded). These are things people touch. So now, because current is flowing on the ground conductor, everything people touch (metal enclosures, equipment cases, etc..) connected to the (green wires) ground has a voltage NOT zero. This could be a shock hazard (though most likely just a little trickle). A bigger problem becomes if a neutral or ground connection then fails and the whole ground system (and metal cases connected) goes to 120V.

I have a main panel out front, and a panel in the house and then A panel in the garage, all are neutral ground bonded. All are fed by 3 wire. 2 ground rods at each.

 

[Jcoon]

I don't understand how a home run wire from the new house to the well will help. Isn't the well pump currently powered through the pressure switch in the old house, at the pressure tank? The new house would need a wire feeding directly to the pressure switch in the old house.

Obviously that痴 what where all saying is power the pump by the new house with a wire in the new trench.

 

[rbstern]

Are you married to the idea of two separate meters? Another option is to just install a single 400a service, with 200a breakers to each house and a transfer switch on the main panel. That way both houses and the well have generator backup, and you only get a bill for one electrical service.

I could live with that solution. The only downside I can think of is, when we're dead and gone, somebody may want to sell this property as two homes. But I suppose that's not really any more problematic than both homes being on a single well.

I'll ask the power company engineer to weigh in on this when he/she comes to the property.

 

[CobyRupert]

I have a main panel out front, and a panel in the house and then A panel in the garage, all are neutral ground bonded. All are fed by 3 wire. 2 ground rods at each.

I assume the main panel feeds the house and garage panel. By code, the ground and neutral should only be bonded with each other at the main panel, and isolated from each other in the sub-panels.
While not to code, what helps in your case is the ground rods at each panel keeping "ground" close to 0 volts even though (normal) neutral current may be flowing on ground conductors.

Neutral current should only be on (white) neutral conductors.
Ground conductors (green) should have no current on them.
It's against code for neutral current to run on ground conductors.

 

[CobyRupert]

I don't understand how a home run wire from the new house to the well will help. Isn't the well pump currently powered through the pressure switch in the old house, at the pressure tank? The new house would need a wire feeding directly to the pressure switch in the old house.

Yes, it's assumed "power to the well or pump" means through the pressure switch, regardless of where the power source is.

 

[Jcoon]

I assume the main panel feeds the house and garage panel. By code, the ground and neutral should only be bonded with each other at the main panel, and isolated from each other in the sub-panels.
While not to code, what helps in your case is the ground rods at each panel keeping "ground" close to 0 volts even though (normal) neutral current may be flowing on ground conductors.

Neutral current should only be on (white) neutral conductors.
Ground conductors (green) should have no current on them.
It's against code for neutral current to run on ground conductors.

Well mine is to code it was inspected this summer of 17 by two different electrical inspectors. Again I do NOT have a 4th wire ground wire going to my panels connecting them.

 

[grsthegreat]

ok, ive run into this same situations on several occasions, as i install lots of whole house generators. first off, one generator cannot power up 2 separately derived houses (separate meters). not allowed. it would be ok only if the property was served by one 400 amp service then using 2 separate 200 amp transfer switches. but thats too crazy to even contemplate here, because the easiest and cheapest way to do this is to run a 4 wire circuit from the new house to the well panel. make sure the well panel is permanently marked with a placard stating where power is derived from. the well pressure switch acts as a dumb switch and can care less where power is derived from.

ive done this multiple times and it works fine.

 

[rbstern]

ok, ive run into this same situations on several occasions, as i install lots of whole house generators. first off, one generator cannot power up 2 separately derived houses (separate meters). not allowed. it would be ok only if the property was served by one 400 amp service then using 2 separate 200 amp transfer switches. but thats too crazy to even contemplate here, because the easiest and cheapest way to do this is to run a 4 wire circuit from the new house to the well panel. make sure the well panel is permanently marked with a placard stating where power is derived from. the well pressure switch acts as a dumb switch and can care less where power is derived from.

ive done this multiple times and it works fine.

Why four wires? If the well pump is isolated as a single branch circuit from the new house, wouldn't it just be the two hot 120v legs and ground?

 

[RSKY]

When Irma came along, we were surprised at how long it took the county and local EMC to get everyone back online. Also, for outages where power is down but phone is up, I can still be connected to the Internet for my work, and sometimes my responsibilities to my clients are urgent enough to bear the expense for backup power.

Okay, I understand. The guy two doors down from me also works at home on a computer. He gets frantic when the power is out. I am retired. So if the power goes out on us it is no big deal. We just cope with it and make do.

One of the reasons I was asking is because of what happened to some around here in after the 2009 ice storm. We didn't have power for more than two weeks and depended on a small 4000-watt generator. Others, and not all women, thought it was the end of the world. NO INTERNET, no Facebook, no chatting, OMG what will we do!!

I spent the first six years of my life in a house without inside plumbing (for water installed in 1960, for bathroom in 1961), no telephone (installed in 1961), no air conditioning (installed 1968), well you get the idea. So it is funny to me that some spent the equivalent of a couple months wages installing whole house generator systems for what they consider necessities that aren't really necessary.

As long as you can stay warm and have something to eat and drink you can survive without power for a while.

BUT if your livelihood depends on having power that puts everything in a different category.

RSKY

 

[CobyRupert]

Well mine is to code it was inspected this summer of 17 by two different electrical inspectors. Again I do NOT have a 4th wire ground wire going to my panels connecting them.

Distracting from OP once again, but : You may be to Code under a (IMHO) rarely used exception.
The 2017 Code (Article 250.35) allows an exception: No ground conductor is required from main panel, and bonding of ground/neutral at sub panels is allowed if "there are no continuous metallic paths..." between the buildings that connected their ground systems. Essentially they allow you not to have a ground conductor (or thinking of it another way, you can use the neutral conductor for a ground fault conductor back to the transformer) if there's no way normal neutral current can use a parallel continuous metallic "ground" path.

I assume you don't use metal conduits to sub panels?
While this exception is allowed, the problem of using this comes if a future metallic connection (water, gas pipes, duct work, etc..) is installed after the inspector leaves, or years down the road and normal neutral current uses it as a path.

 

[rbstern]

Okay, I understand. The guy two doors down from me also works at home on a computer. He gets frantic when the power is out. I am retired. So if the power goes out on us it is no big deal. We just cope with it and make do.

One of the reasons I was asking is because of what happened to some around here in after the 2009 ice storm. We didn't have power for more than two weeks and depended on a small 4000-watt generator. Others, and not all women, thought it was the end of the world. NO INTERNET, no Facebook, no chatting, OMG what will we do!!

I spent the first six years of my life in a house without inside plumbing (for water installed in 1960, for bathroom in 1961), no telephone (installed in 1961), no air conditioning (installed 1968), well you get the idea. So it is funny to me that some spent the equivalent of a couple months wages installing whole house generator systems for what they consider necessities that aren't really necessary.

As long as you can stay warm and have something to eat and drink you can survive without power for a while.

BUT if your livelihood depends on having power that puts everything in a different category.

RSKY

If I was retired, I'd be less inclined to worry about it. My favorite days are the ones where I'm outside all day, and blissfully unaware of what's happening in the rest of the world.

 

[CobyRupert]

So it is funny to me that some spent the equivalent of a couple months wages installing whole house generator systems for what they consider necessities that aren't really necessary.

RSKY

Most technology (even indoor plumbing, power etc..) goes through at least 3, and usually 4 phases: 1)Luxury, 2)Convenience 3)Necessity 4)Obsolescence.
Where you are in the cycle of a particular technology varies by individual.

 

[bcp]

I would like to see the replacement for electric power and indoor plumbing, when they are obsolete.

Lights and appliances with lifetime batteries? Matter transfer toilets and faucets?

Bruce

 

[CobyRupert]

I would like to see the replacement for electric power and indoor plumbing, when they are obsolete.

Lights and appliances with lifetime batteries? Matter transfer toilets and faucets?

Bruce

Replacement and obsolescence are two different things. Rome had indoor plumbing before it didn't. Plumbing discovery reveals the rise and fall of the Roman Empire | Ars Technica
The U.S. west has water (and plumbing) right now, but....

 

[RNeumann]

How about a simple automatic transfer switch that only feeds the well? Normal power comes from the old house and when the power goes out the transfer switch switches to a circuit off the generator.
You won’t need any of the gen start features in the transfer switch as that will be handles by the “main” transfer switch.
I’ve never done this nor have I studied code enough to see if an isolated circuit can be fed by a separate service entrance. But if that’s truly code this would be a work around that I assume would meet code.
If code isn’t an issue (and I don’t think it is) I’ll stand by my first thought in one of the first posts in the thread.

 

[rbstern]

Remove the well control circuit from the old house, and control it totally from the new house. The water connecting line from the new and old houses puts both water systems in parallel. Therefore, the well could be controlled from either place. You must account for any voltage drops. As a side note, you haven't given us the size of your current pump. You must also consider how many wires will be needed; ground, two hots (240V) and maybe a start wire as is used on many bigger pumps. With this setup, you don't have to be concerned with an automated (manual) transfer switch in the old house for the well.

Note sure you mean parallel. The new house is just treated as a fixture off the single water system, like any fixture in the existing house.

Don't recall the size of the current pump (and I'm 80 miles from it at the moment). It's on a 240v 30 amp breaker, 2 hots and ground. One other wrinkle in terms of wiring it to the new house panel is the distance. It's already about 300 feet from the existing house, and the new house is another 150 feet way.