Pump just died, panic mode engaged.

[Bperry]

That's not strictly true though is it? If I run my single speed pump for 4 hours at 2850 rpm to get a single turn over, I'd need to run a VS pump at 1425rpm for 8 hours to achieve the same, no?

“Turnover” is an old industry term that’s more myth than reality. You run the pump for specific reasons:
1. Skim debris from the surface into the filter
2. Mix chemicals/generate chlorine
3. Enable water features/cleaning tools

The amount of time and at what speed is dependent on those things, not an arbitrary amount of “turnovers”.

Agreed, that's why I gave two savings of 50% and 75% and to see what that monitory saving would look like.


Am I though? If I had rushed out and bought the first VS pump I could find (any VS pump it would seem), I'd have to return it because it was single phase and I have 3 phase.

I simply meant that if you are ok with the current setup that there’s nothing wrong with it. You obviously can’t just go out a purchase ANY pump at all without ANY thought. You mentioned having an electrician doing the work so I assumed he was competent enough to know the difference in phase requirements. You have somewhat unique requirements/limitations.

 

[Darin]

I said something earlier about "why would I buy a VS pump + VFD if I can buy a SSP + VFD and achieve the same outcome for considerably less $?". Well, talking to my electrician yesterday, he wasn't very keen on installing a VFD for my 3 phase single speed pump because "the pump wasn't designed to be run at slower speeds". I initially dismissed this (in my head) as some of you guys have been doing this for years but then I read that VS pumps are built differently, with permanent magnet motors. Hmm, so maybe just reducing the power has drawbacks? Why would they design a completely new motor if all they had to do was add a box of tricks that reduced the power?

The pump does not care what speed it runs as long as it is primed. Obviously you can over speed it but not under speed it. I don't run my motor less than 25 hertz (60 Hz in USA) on my pool because that is what it needs and my motor always has enough fan cooling. All you need to do is run it fast enough to make sure your skimmers work and if you have a SWG fast enough to generate chlorine.

Pumps are not built differently. The pump does not care what type of motor is driving it. Single speed, dual speed, or VS.

The standard motor can be used on small pool pumps without the insulation class "F" as many are. The static build up frequently written about are in HVAC situations where the motors are constantly ramping up and down for HVAC efficiency HVAC is where the bearing static problems occur. This does not happen in our situation because pool owners with a VFD on a three phase motor don't adjust speed much because we are after slowest speed we can operate to keep the pool equipment functioning properly. Every pool needs a little bit different speed and thus the speed is controlled by adjusting hertz in the VFD. Again, slowest speed means savings on electrical meter. The only time i run wide open is on initial pump start up after maintenance and vacuuming then i slow it down.

The only down side to operating this way is money savings and a quiet pump.

Permanent magnet motors are a bit more efficient than the standard motors, but i cant tell you how much because i don't have one to swap in to measure with an amp clamp.

So again you are back to the three options to save money.
1. buy a like motor and add a VFD
2. buy a new add on motor that has VS included like a V-Green as sold here in the USA.
3. buy a complete new VS pump and motor package to replace you motor and pump. There has to be something sold in your market. Otherwise import one from USA and use a step down transformer. ($$)

By the way what three phase voltage do you have to the pump?

 

[Desiato]

“Turnover” is an old industry term that’s more myth than reality.

Fair enough. I keep seeing it though out there in the pool world but it does vary between 2 to 3 turnovers but most on here were saying way back when that 1 turnover / 4 hours was enough.

You mentioned having an electrician doing the work so I assumed he was competent enough to know the difference in phase requirements.

I mentioned that my friendly electrician was trying to fix the pump and when he returned with it yesterday we talked about VFD's and if that was a viable option. I don't see anywhere that I said I'd talked to the electrician about phase requirements, he doesn't even know I'm thinking about changing the pump yet so it hasn't cropped up in the conversation.

You have somewhat unique requirements/limitations.

I have a 3 phase supply, that's pretty much my only limitation. I would like a variable speed pump, is that a unique requirement? The two don't seem to fit hand in hand very well though, that's my problem.

 

[Desiato]

The pump does not care what speed it runs as long as it is primed...Pumps are not built differently. The pump does not care what type of motor is driving it. Single speed, dual speed, or VS....Permanent magnet motors are a bit more efficient than the standard motors, but i cant tell you how much because i don't have one

Ah, right. The article I read stated that VR pumps had magnets and stated it as a matter of fact as if they were all that way.

So again you are back to the thee options to save money.
1. buy a like motor and add a VFD
2. buy a new add on motor that has VS included like a V-Green as sold here in the USA.
3. buy a complete new VS pump and motor package to replace you motor and pump. There has to be something sold in your market. Otherwise import one from USA and use a step down transformer. ($$)

Number 1 looks to be the obvious choice.

2 and 3 just leads to more questions. Can I get an add on motor that has VS included for an Astralpool Victoria Plus 38774? How would I know if it was compatible? Are there different sizes and different power requirements? Am I overthinking this? Yes! If I don't ask these questions will I get it wrong? Absolutely! Number 3 brings me back to the 3 phase/VS pump incompatibility. I did eventually find one here...£3735 (from the UK) So they do exist but, yeah, no.

I now know that one end of the pump is the motor, the other end is the pump. It's only easy when you know and if you don't know, you don't know...now I know.

By the way what three phase voltage do you have to the pump?

I had to change the cheap Chinese timer clock last year and it had to be 220v. That's the best I can do at the moment as the electrician is busy elsewhere. I've never seen any documentation mentioning 400v, I've never heard anyone talking about 400v, I've only ever seen 220v mentioned on any appliance but I can't say with 100% certainty that there isn't 400v going to the pump because I don't know. Does that help?

 

[Darin]

Sounds like you have three phase 220V since your appliances and your timer is that. My motor is a three phase 220V.
Turnover is still a myth that is repeated over and over. Ignore it.

 

[Bperry]

Fair enough. I keep seeing it though out there in the pool world but it does vary between 2 to 3 turnovers but most on here were saying way back when that 1 turnover / 4 hours was enough.

I mentioned that my friendly electrician was trying to fix the pump and when he returned with it yesterday we talked about VFD's and if that was a viable option. I don't see anywhere that I said I'd talked to the electrician about phase requirements, he doesn't even know I'm thinking about changing the pump yet so it hasn't cropped up in the conversation.

I have a 3 phase supply, that's pretty much my only limitation. I would like a variable speed pump, is that a unique requirement? The two don't seem to fit hand in hand very well though, that's my problem.

I didn’t mean any offense. I just assumed the electrician would be advising what the requirements are, not that you are acting as the contractor and just asking him to wire it up. I don’t know anything about pool pump availability in Spain and it sounds like from your research that there aren’t any variable speed pumps that run on 3phase power, but I haven’t researched that to know. That’s all I meant about a unique requirement.