Pump disconnect

[dkarst]

Constant Pressure systems vary. Franklins use a simple on/off pressure switch and not a transducer. I haven't taken the time to watch but my local pump installer says you can watch the pressure change ever so slightly as it cycles.

I believe my Franklin SubDrive (constant pressure system) uses a pressure transducer, not a simple on/off switch to control the VFD which controls the rpm of the motor which is down the well. As the pressure drops, the VFD spins the motor at higher rpms. The output spec is 30 - 80 Hz.

 

[Open Neutral]

For me, this has been an informative thread. Looks like my plan to put a padlockable breaker on the VFD will meet the letter of the Code as well as being safe, [IMHO].

I'll have to see (mechanically) how best to do that; maybe the 240 breaker that will feed the xfmr.

 

[gndrod]

VFD for homes

VFD for homes

I believe my Franklin SubDrive (constant pressure system) uses a pressure transducer, not a simple on/off switch to control the VFD which controls the rpm of the motor which is down the well. As the pressure drops, the VFD spins the motor at higher rpms. The output spec is 30 - 80 Hz.

That may be a 3 ph conversion AFD you are referring for a constant pressure system. If the energy source is 1 ph, this is not an efficient use for a submersible design. With economy in mind (unless the well is supplying a large agri irrigation system) most water supply configurations installed for a simple residential set up... the 1 ph pump and storage consisted of a 2 pole pressure on-off switch that controls filling a captive tank without a VFD or 3-wire conversion.

A 2-wire 1.0 hp 10 GPM pump-motor configuration matched to a sustained draw down well capacity can service a 2500 sf dwelling, water the horses and still irrigate the front lawn daily without any problems. The 40-60 setting on a captive 80 gal (220 gal equiv) tank maintains household line pressure down to 30 psi for minimum plumbing standard without constant pressure pump activity. I have set quite a few country homes over the years without any failures and maintain that overspending for installing McMansion systems as wasteful and only for the very rich who don't seem to give a concern.

I inspected one such residence in S. Cal recently and saw the domestic supply 35 GPM pump, with 3 ph VFD control, feed the 6 brm, 4 bath home using a constant pressure 12 gal captive tank for the system. The owner had money falling out of his pockets and was shocked when I told him his fancy system would fail during an energy outage after four flushes. A look of amazement on his face was indescribable. Every set up is different and depends on the professional experience of the installer and what the client is willing to spend.

 

[hurk27]

For me, this has been an informative thread. Looks like my plan to put a padlockable breaker on the VFD will meet the letter of the Code as well as being safe, [IMHO].

I'll have to see (mechanically) how best to do that; maybe the 240 breaker that will feed the xfmr.

Only if your breaker is within sight from the controller.
Nope you missed the part that also requires the disconnect to be within sight of the controller 430.102(A)

430.102 Location.​

(A) Controller.

An individual disconnecting means shall

be provided for each controller and shall disconnect the
controller. The disconnecting means shall be located in​

sight from the controller location.
​

so a disconnect has to be insight of the VFD controler
​

 

[gndrod]

The controller logic/VFD/etc is all in a mech room in the basement. The well is outside, with not much visible.

So if I can padlock the breaker, that's a plus.

SQ D's FSG2124 M4CP 2 pole pressure switch has a lockout option on the override handle that will be adequate at the tank location sans VFD.

 

[Open Neutral]

SQ D's FSG2124 M4CP 2 pole pressure switch has a lockout option on the override handle that will be adequate at the tank location sans VFD.

Only if your breaker is within sight from the controller.
Nope you missed the part that also requires the disconnect to be within sight of the controller 430.102(A)

The feeding panel, stepup xfmr and VFD shall be adjacent on the one wall of the electrical room in the house basement. As well the other panels, [3-4 of them] and other stuph.

There are no pressure switches involved. The 2HP Franklin pump fills the 20,000 gallons of unpressurized tank storage, about 25' above the house. Given we are pushing the pressure rating rather of the well pipe; there are zero valves in the outflow.

A float switch starts and stops the Franklin; a flow switch & timer provides no-flow/run dry protection.

A separate pump with internal VFD [likely "AquaBoost"] in the wet room uses that water for both domestic needs and the 13D interior sprinkler system.

 

[hurk27]

E'rrrr Fire system?

 

[hurk27]

not sure but these pumps could fall under the NEC 695 requirments?

 

[ptonsparky]

That may be a 3 ph conversion AFD you are referring for a constant pressure system. If the energy source is 1 ph, this is not an efficient use for a submersible design. With economy in mind (unless the well is supplying a large agri irrigation system) most water supply configurations installed for a simple residential set up... the 1 ph pump and storage consisted of a 2 pole pressure on-off switch that controls filling a captive tank without a VFD or 3-wire conversion.

A 2-wire 1.0 hp 10 GPM pump-motor configuration matched to a sustained draw down well capacity can service a 2500 sf dwelling, water the horses and still irrigate the front lawn daily without any problems. The 40-60 setting on a captive 80 gal (220 gal equiv) tank maintains household line pressure down to 30 psi for minimum plumbing standard without constant pressure pump activity. I have set quite a few country homes over the years without any failures and maintain that overspending for installing McMansion systems as wasteful and only for the very rich who don't seem to give a concern.

I inspected one such residence in S. Cal recently and saw the domestic supply 35 GPM pump, with 3 ph VFD control, feed the 6 brm, 4 bath home using a constant pressure 12 gal captive tank for the system. The owner had money falling out of his pockets and was shocked when I told him his fancy system would fail during an energy outage after four flushes. A look of amazement on his face was indescribable. Every set up is different and depends on the professional experience of the installer and what the client is willing to spend.

I don't see a problem, I see an opportunity to sell a gen with autotransfer.

 

[gndrod]

I don't see a problem, I see an opportunity to sell a gen with autotransfer.

I agree now that Open Neutral has fully disclosed the 20,000 gal static system used. Wayne brings up a good point about the fire system requirements. The storage may not have enough head for minimum pressure through a fire hose. As far as I can remember, the insurance company requires a 75 ft. stream from the nozzle for a qualifying rate from a 50' head. A secondary pump does fit the solution.

 

[Open Neutral]

perhaps more than you wanted to know.....

perhaps more than you wanted to know.....

A) CalFire requires the home have 10,000 gals on hand, unless you have city water. This house will have 20, really 30 if you include the rainwater tank, and 40+ if you count the pool. (CalFire does NOT, based on bad experiences...)

B) Califunny requires sprinklers in all new construction, and Santa Cruz County did so before the state requirement. This per NFPA 13D.

Further, since they soon found out no homeowner would ever maintain a fire pump; they require the sprinklers be fed off the potable system, with no valve to shut them off without also ixnaying the house H2O. (If you have enough static head, no pump is needed...) They also require spare heads and a wrench be on-site.

Since the sprinkler GPM requirement is far more than most domestic use; the SOP has become packaged VFD-driven systems, aka "Aquaboost" or competitors. They go into high speed when a few heads open. Our pump is ~30 ft below the tankage.

C) I can find no special requirements for backup power for the 13D pump, or other such rules. The Fire Marshal confirms that. Nevertheless, we will have the pump on the Priority 1 panel, where it gets fed by 20KW of backup inverters; those recharged by the solar array &/or a pad-mounted 25KW propane generator. THAT is backed up by a PTO-driven generator on a Diesel tractor.

D) This 13D pump is separate from my discussion on pump disconnects. THAT is about the 670 ft down, 2HP, 480v3ph. well pump that refills those 20K worth of tanks. (Well, it and the other well, driven by a solar array...)

E) As for fire streams, there's a 4" line from the tanks to the wharf-head hydrant, & it must be between 50 & 150 ft. from the house, and from 6-8 ft from the road, with a turnout for other apparatus to pass the engine at the hydrant. It shall be marked with a blue dot, etc. You can get started Here, if you are bored....

 

[weressl]

The controller logic/VFD/etc is all in a mech room in the basement. The well is outside, with not much visible.

So if I can padlock the breaker, that's a plus.

So if a well pump is hundreds of feet into the ground, how can you install a disconnect within sight of it?

 

[ptonsparky]

So if a well pump is hundreds of feet into the ground, how can you install a disconnect within sight of it?

I see two ways around this.

1: Put a lockable disconnect within sight of the controller as permited for this type of installation.

2: Put a disconnect at the well head. When you pull the pump up out of the hole it will be within sight of the motor. or refer back to 1.

 

[gndrod]

Super system..

Super system..

A) CalFire requires the home have 10,000 gals on hand, unless you have city water. This house will have 20, really 30 if you include the rainwater tank, and 40+ if you count the pool. (CalFire does NOT, based on bad experiences...)

VFD-driven systems, aka "Aquaboost" or competitors. They go into high speed when a few heads open. Our pump is ~30 ft below the tankage.

C) I can find no special requirements for backup power for the 13D pump, or other such rules. The Fire Marshal confirms that. Nevertheless, we will have the pump on the Priority 1 panel, where it gets fed by 20KW of backup inverters; those recharged by the solar array &/or a pad-mounted 25KW propane generator. THAT is backed up by a PTO-driven generator on a Diesel tractor.

(Well, it and the other well, driven by a solar array...)

if you are bored....

Open Neutral,

Not bored at all. Thanks for the additional data. Evidently this is no shack residence and probably up on Skyline. Things have really gotten high-Tech since I moved to the sticks some time ago. Just curious...Is the solar backup well a stand-alone and is it a dc direct or conversion driven? I had no idea of how things changed. I feel like a hick now that you described the project. My days of being economical have been overshadowed by what you are doing. Best of luck. Tx

 

[Open Neutral]

First, it's not "my" work. The builder-owner is hands-on; he built his last two houses himself; as in: bought skidloader, dug foundations, took the local tests [w/spouse] then did did own wiring & plumbing and roofing and windows....This time around, he's less able - he hurt his back badly on that one, and has far less time thanks to his Day Job responsibility.

There's a local licensed contractor, electrician, architect, coordinator;....and then the [literally] $100K worth of experts and plans Santa Cruz County requires before he gets a building permit. They alone are more money then the last house cost the two of them.

He's a friend, he trusts me to ask [sometimes blunt] questions, and maybe answer them. He pays me well enough; but I can tell & do him he's wrong.

This is in a redwood forest/treefarm in NorCal; carefully set to cause no trees to be cut. There's an attached poolhouse. [Dijaknow that an interior pool, with concrete/tile deck, must be sprinkled to meet 13D? I was worried the water would catch on fire was how he put it...] The power part is only a fraction of the tasks; there's also the water, the HVAC and comms -- he and his spouse's jobs are highly dependent on good 'net access but that's making the PG&E issues look easy. He's 5 miles from a 1600 ft antenna on a 2000 ft. mountain, and we can't see it....

He really hates it when the water fails at his current suburban house. Even if ALL power fails, or the 13D pump; at least the 1st fl and basement toilets will flush, and with 20K of water reserve, you don't go thirsty.

Best part may be the neighbors; basically the decadents of the old man who homesteaded the area in ?1860? There is a collective "tool library" where you can borrow things.....things like a Fiat-Allis HD 30 {~Cat D6}, a road grader, backhoe, 9000# offroad forklift, Ditchwitch, and such.

The solar system... There will be SMA Sunny Boy backup inverters 4x5KW. Then somewhere around that of Sunny Island grid-tie units, SMA promises that after PG&E takes the day off, and the ATS has swung over; the grid-tie units will come back up and get in sync with the backup ones, recharging the battery bank even without the generators, iffen there's sun enough. And if the generator is commanded on, the SMA's get in sync with it, reducing its loading.

We were doing it all in 3ph, with 480/277 from PG&E, but the PG&E connection charges plus other issues forced us back to 240/120, saving ~$40K. Even so... Today I was told they will not accept 2" Schedule 80 HDPE for the primary feed; it has to be the far weaker DB120 PVC. The pullbox they require, a 025601, is $2500. I think the concrete is laced with gold. Plus, their Greenbook's links, every one, are broken.

But it's fun to learn so many new things.

 

[gndrod]

Wellhead 1...controller 0

Wellhead 1...controller 0

I see two ways around this.

1: Put a lockable disconnect within sight of the controller as permited for this type of installation.

2: Put a disconnect at the well head. When you pull the pump up out of the hole it will be within sight of the motor. or refer back to 1.

Definitely a difficult answer to get past the CMP. I would choose door no. 2 for a simple solution. There seems to be a very important concern for describing the different definition of 'controllers' that exist also.