So far the only 230VAC single-phase, two-wire controller I've found that's designed to retrofit existing systems like mine is a Franklin SubDrive2W. It's not a soft-start controller, but a constant-pressure VFD that has soft-start. (I think. That is unclear. But their other SubDrive models do.)

Problem is: The manufacturer doesn't talk to Joe Homeowners and their only sales references are to well companies--one of which is the one we use.

I downloaded and examined the installation manual. It's pretty straight-forward.

There's one for sale, NIB, on eBay, for $400, but I expect I'd be buying an item with no technical or other support at all--incl. warranty support.

quote:

Originally posted by Rustpot:
While the industrial pricing for a 1hp ABB VFD might be <$500 the plumber is likely not sourcing from OEM industrial supply shops and is paying closer to list price. I don't think $1400 is bad at all, considering he might be making $200 on it.

I like Grundfos pumps. Depending on size and features $1400 probably isn't too bad of a price. They make pretty much all of their pumps with integral VFD options now, it's noted by an extra 'e' on the model. For instance CR are their vertical multistage inline, CRe is another model line but is the same pump with a VFD motor on it. I have OEM pricing through them. I can at least look to see how bad of a price you're getting, or potentially sell you the pump when you're ready (depending on several things) since you're somewhat local. At the very least I can get the full performance characteristics and diagrams for it.

I don't have a ton of familiarity with home systems and single phase setups, but I design water circulation and heat transfer systems for industrial equipment and customers. Pressure, flow, piping, pumps, all that I can do. I have a dedicated team for controls, so I'm not well versed in getting soft starts and VFDs configured.

This sounds like the way to go...… Replace the 22 year old pump and Install a new Grunfos with build in VFD.

Another possibility, are there any 240 volt variable speed pumps? They start up very slow and then start cranking as more flow is needed to meet pressure provided you have an appropriately sized expansion tank.

I spoke to the GM of our water co, we use Grundfos pumps with Yaskawa VFDs. Not sure we knew you could get an integrated pump VFD.

I would've sworn I followed-up and thanked you, Rustpot

Thanks for the info and the offer, but I think we're just going to let the current pump live out its life and replace it with a Grundfos soft-start pump when the time comes. At that point it'll only be about a $600 difference from replacing with the equivalent to the pump we've had, and that's tolerable.

I've talked to my well guy about Grundfos VFD models. We could put in a 2-wire VFD-capable model and add the VFD later. It'd be soft-start only until then. But he and many of the other well guys around here apparently had a very bad time with Grundfos VFD controls the first few years they made them. He said one local distributor even dumped Grundfos entirely over the problems. He'll quote it, but, if we want a VFD system he'd feel more comfortable with a Goulds three-phase system.

This decision may come sooner, rather than later. Asked him "If our pump is going, will we get any advance warning?" "In my experience they usually just up and die, with no warning. Usually at the worst possible time," he replied. So I asked, "Ok: What, in your experience, is the average lifetime of a residential submersible well pump?" "Both my dad's experience and mine, from 2 in. metal jet wells to 5 in. plastic, regardless of pump, about 15-17 years," was his answer.

If he's right, we're on about five years borrowed time.

Now there's a comforting thought

Pump life comes down to three things - the wet end, the motor, or the seal.

Anything in the wet end, meaning the actual parts that see water, would be limited to corrosion or excess wear. Things just eroding away, falling apart or seizing up.

Similarly, the motor, to include it's shaft into the pump, typically runs until it just burns out or seizes. More commonly something like a bearing will go out, but pumps can run a long time on bad bearings. Small motors of that type are typically permanently lubricated, and if run clean with minimal exposure to moisture (no internal corrosion), and staying at or below operating temperature (no degradation of the insulation on the windings), can run for 50+ years. There are a ton of motors in service in industrial applications that are very similar that are from the 60's and 70's.

The biggest failing point of pumps is the seal between the motor and wet end. Water getting in the motor is bad. Pump designs are all different for different reasons, a lot of variations on designs are just different ways to treat the seal. Depending on the design of the pump, this seal can play a very important mechanical role, and in other cases this seal is as simple as an o-ring.

It could be a motor that's starting to go that's causing a high current draw and prolonged strain on your generator. It could be leaking like a sieve but still doing enough work to serve your needs. No way to tell without going and taking a look and measuring.

As for brands I don't really care to get involved in endorsements or recommendations. I'm not servicing your equipment, I don't know the local reps and how good they are. I know my OEM support staff and I have a team of professionals to take care of issues I have, so my experience is worth very little to you. For what it's worth, Goulds is a Xylem brand, and I have an account with Xylem. I buy from them somewhat often, mostly their Bell & Gossett products. My Goulds guy takes forever to answer email questions and issues, that's part of why I don't use them as much .

quote:

Originally posted by Rustpot:
Small motors of that type are typically permanently lubricated, and if run clean with minimal exposure to moisture (no internal corrosion), and staying at or below operating temperature (no degradation of the insulation on the windings), can run for 50+ years. There are a ton of motors in service in industrial applications that are very similar that are from the 60's and 70's.

Yeah. He said "I'm not trying to sell you on anything. That pump could easily run for another ten years or more."

I think he's being straight with me. Hell, he had the opportunity to sell us a new pump three years ago when, due to the way the system was sounding and acting, we thought the pump was dying. It wasn't. The bladder in the expansion tank had sprung a leak. So it was just a new expansion tank. And, because we bought the new tank from him and had him install it, he waived the initial service call fee.

I've talked it over with the family CFO. We're thinking on it. I suspect the longer we think about it the more likely "rolling the dice" will be our decision

Yesterday I placed an order with our well guy for a Goulds 3AS20 Aquavar SOLO2 VFD controller with in-line transducer and 18GS10 pump (WE) with M10432 three-phase, 240VAC motor.

Was quoted a bit over $4k, installed.

Our existing 18GPM, 1HP, 240VAC, single-phase pump maintains 61 PSI with six 3 GPM irrigation heads running, and the new pump, with the VFD controller, should be fine with our 4KW constant, 5KW surge generator.

I finally decided to bite the bullet and pay for the more expensive solution when I determined that only two of our eight irrigation zones had high enough flow rates to keep the pump from cycling. The VFD controller will eliminate that problem entirely--saving energy and wear-and-tear on the pump.

I'll update once it's all in and let y'all know how it works out.

In my building all of our fan and pump motors are VFD drives. Most ran perfectly from the initial set up. For the ones that didn't our issues have been fairly minor over amp issues with the problem being the timing of the acceleration curve. It's an easy thing to adjust and it's done through the touch pad. From a standpoint of power consumption if you run a motor off a VFD you will see an increase in power consumption if you run it over 90%. You probably won't notice it if you well pump is the only thing that's on a VFD. In a commercial application like the one I work in it amounts to big bucks.

quote:

Originally posted by SgtGold:
From a standpoint of power consumption if you run a motor off a VFD you will see an increase in power consumption if you run it over 90%.

We actually expect to see a decrease in energy consumption, since it's that big surge in an on/off pump system that costs the most, and that will go away.

The only time the pump will run at or near 100% capacity is when three of our eight irrigation zones are running. Two of them consume 18 GPM. A third used to, until I replaced a 3 GPM head with a 1.5 GPM mister. (That's a worst-case scenario: A zone that almost, but not quite, runs the system at capacity.)

quote:

Originally posted by ensigmatic:

quote:

Originally posted by SgtGold:
From a standpoint of power consumption if you run a motor off a VFD you will see an increase in power consumption if you run it over 90%.

We actually expect to see a decrease in energy consumption, since it's that big surge in an on/off pump system that costs the most, and that will go away.

The only time the pump will run at or near 100% capacity is when three of our eight irrigation zones are running. Two of them consume 18 GPM. A third used to, until I replaced a 3 GPM head with a 1.5 GPM mister. (That's a worst-case scenario: A zone that almost, but not quite, runs the system at capacity.)

One of the things that's been discovered with mass VFD conversions is just how many devices don't need to run at even 90% to satisfy load or safety switches. You might want to take this time to determine exactly how big of a motor you need to satisfy 100% of your demand, then up size the motor to the point where running it at or just below 90% gives you what you need. The overall cost might not be worth it, or take too long to amortize, but now's the time to do the math.

quote:

Originally posted by SgtGold:
You might want to take this time to determine exactly how big of a motor you need to satisfy 100% of your demand, then up size the motor ...

I already know these things.

On paper, two of our three irrigation zones run the pump at 100%. 18 GPM pump. 6 x 3 GPM heads. So, on paper, going up to a 1.5 HP, 20 GPM pump would've been ideal. Except there's the little problem of our emergency generator, which is rated at 4KVA, 5KVA surge. The 1.5 HP pump would exceed the generator's capacity.

See my OP in this thread for a refresher on the generator issue.

You are failing to take into account that a VFD eliminates the locked rotor amperage (LRA) that occurs when you hard start. It's the LRA that determines how many amps draw that the circuit needs to safely run under. Your new pump only needs about 10a to run at maximum output, but can draw almost 50a on startup.

Edited because my math was wrong.

quote:

Originally posted by ensigmatic:
On paper, two of our three irrigation zones run the pump at 100%. 18 GPM pump. 6 x 3 GPM heads. So, on paper, going up to a 1.5 HP, 20 GPM pump would've been ideal. Except there's the little problem of our emergency generator, which is rated at 4KVA, 5KVA surge. The 1.5 HP pump would exceed the generator's capacity.

See my OP in this thread for a refresher on the generator issue.

This message has been edited. Last edited by: SgtGold,

quote:

Originally posted by SgtGold:
You are failing to take into account that a VFD eliminates the locked rotor amperage (LRA) that occurs when you hard start.

No, I am taking that into account. Again: Please see my OP.

The original idea was to switch to a soft-start pump to eliminate that huge current surge regular pump motors have. It was after further discussion I found that I could both eliminate that and the repetitive on/off cycles during irrigation that I went with a VFD solution.

quote:

Originally posted by SgtGold:
Your new pump only needs about 10a to run at maximum output, but can draw almost 50a on startup.

Both new and old pumps are 1HP, 18GPM pumps. Only difference is the current one is 240VAC single-phase and the new one is 240VAC three-phase. The only increase in energy budget will be whatever efficiency losses are incurred by the VFD electronics. I expect that may be offset by the increased energy efficiency of the three-phase motor.

I don't know where you're getting a 50A starting surge on the new system. It's a soft-start controller. Gould's own docs say my 4KVA generator with 5KVA surge will be sufficient.

A 50A starting surge would require a 12KVA generator.

quote:

Originally posted by ensigmatic:
I don't know where you're getting a 50A starting surge on the new system. It's a soft-start controller. Gould's own docs say my 4KVA generator with 5KVA surge will be sufficient.

A 50A starting surge would require a 12KVA generator.

I missed the post where you ordered the system. You will like the ability to tune the VFD controller.

quote:

Originally posted by SgtGold:
I missed the post where you ordered the system.

Yeah. I did lots of research, then confirmed my findings with my well guy, who'd talked to the application engineers at Xylem/Goulds.

quote:

Originally posted by SgtGold:
You will like the ability to tune the VFD controller.

There are a number of tunable parameters, but soft start isn't one of them. This VFD always soft-starts the motor.

Gould's installation doc for this controller recommends a minimum 3500 VA generator for a 1HP, 18GPM, 3-phase motor. The 1-1/2 HP motor recommendation is a minimum 4400 VA generator. I felt that would have been pushing my luck, and 18 GPM is all we really need, anyway.

The only time we'd possibly exceed that capacity is on mornings the irrigation system's running, one of the two zones that actually consumes 18 GPM is running, and the water softener is back-flushing. Even then we'd only exceed system capability by 1-1/2 GPM.

Unless somebody gets up and flushes a toilet, too

Update

Day-before-yesterday our well guy got out here to replace our 22-year-old Goulds 240VAC, single-phase, 1 HP, 18 GPM pump with a Goulds 3-phase, 1 HP, 18 GPM pump and a Goulds VFD.

This new system rocks! Even running full-out, on an irrigation zone with which it can just keep up, it's drawing only slightly less than 6A on the single-phase supply side. Since it's a soft-start controller, that's about the most it'll ever draw. So Goal Number 1: Fixing our past problem with start-up while on generator should be a thing of the past.

I also verified the pump starts up and runs when the first zone starts, and never stops again until the entire program of eight zones ends. That should save us electricity and wear-and-tear on the pump.

Bonus: Even though on paper the new pump is rated the same as the old (1 HP, 18 GPM), it's delivering more water, at higher pressure than the old pump was. I can see it in how far the bigger irrigation zones are throwing water and we can tell in the showers.

Showering is especially nice, now that pressure is limited to a max of a 5 PSI swing, rather than the 20 PSI swing with the old, mechanical pressure switch

The new pump starts and runs so smoothly, so quietly, that, were it not for the blinking light that tells you it's running you wouldn't know unless you listened real carefully.

Another bonus: As part of the pump replacement the well guy was able to inspect the condition of the pump he removed, flush-out the well point, and test the well's capacity. He was amazed at the condition the old pump was in after being down there 22 years ("You have an exceptionally clean well," he told us). Pumping high-pressure air down there to flush the well point and gauge well capacity, he told us the capacity of the well was well beyond any demand we could ever reasonably put on it, so that was good news, as well.

I'm very glad we did this.

Oh, third bonus: Because I helped, he knocked $150 off the bill

Update The Second

We had storms come through just about two hours ago. Power blinked three times, then a fourth time and stayed out.

Fired-up the trusty old Generac gasoline-powered generator--made back in the day Generac still made good portable generators.

The original goal for the water well pump has been realized: The new well pump comes on so gracefully you can barely hear the difference in the generator's running

What's truly wonderful about this is that, not only do we not have to upgrade the generator, but this smaller generator, being more fuel efficient, runs longer on less fuel than would a bigger generator. This 4000W/5000W generator will run 13-1/2 hours on four gallons of gasoline at half load, and it's usually loaded far more lightly than that

I missed this thread as I was out of CONUS when it was posted but found it very interesting. Our Gould’s pump (don’t remember the size (1.5 hp?) has been in our well for 22 years so I guess it’s living on borrowed time...but I will keep the soft start option in mind when that day comes. Thanks.

I have a Gould 1 1/2 HP irrigation pump that has been in use since 1961. I will run four sprinklers at 6 GPM.