Need Pool Pump VFD

[bellington]

I have a 5 HP pool filter pump running on 208. I would like a smart VFD to maximize flow rate and electrical usage. AND I want to control start/stop with a 120 volt AC signal. What are some dependable VCDs that will do that?

Thanks,

Byron

 

[bellington]

VFD, not VCD.

 

[zbang]

You'll need more than just a VFD if you really want to control things. Wanna expand on the plan for us?

 

[bellington]

The pool system will be operated by a Jandy Aqualink RS Model RS-P8 with 120 volt feed. The 5 HP pump motor is a Baldor 3 phase pump. Specs list a CES PFDx-5-4X-2XX-196 as the VFD. I can't find anything information on that number. So, I can't get a replacement. I want something that will operate the pump at the optimum, with no other input than the start/stop 120 from the Jandy Aqualink RS.

 

[ptonsparky]

About any of them. AB, Yaskawa, several options from Automaton Direct. All low voltage digital and analog IO, plus other options. Anywhere from a few hundred on up to hold your breath.

 

[ptonsparky]

The pool system will be operated by a Jandy Aqualink RS Model RS-P8 with 120 volt feed. The 5 HP pump motor is a Baldor 3 phase pump. Specs list a CES PFDx-5-4X-2XX-196 as the VFD. I can't find anything information on that number. So, I can't get a replacement. I want something that will operate the pump at the optimum, with no other input than the start/stop 120 from the Jandy Aqualink RS.

Any VFD will do what you want it to do, but I don’t think you know yet. You need feed back of some sort.

 

[kwired]

How will you know what is optimum?

Seems the pump should been selected for what is needed for the size of the pool.

Or are you wanting to get say 4 HP of work out of it because that is all that calculations say are needed and you can only get a 5 HP motor and maybe limited or no selection on what impeller goes on the pump?

Does one need to vary speed of such a pump or would it always run at a pre determined speed?

 

[Jraef]

Specs list a CES PFDx-5-4X-2XX-196 as the VFD.

CES is (was) a supplier, recently taken over by a larger company called Aquafinity, but they don't make the VFDs. Their VFDs are Yaskawa and although CES packaged them for their equipment, the drives inside were no different from what Yaskawa sells direct. But that series is no longer supported anyway.

But that Jandy unit only turns the pump on and off, it doesn't have any capability of deciding what speed it should run at, so just having a VFD is not going to accomplish that on its own. That's likely what the CES packaged unit was going to do. So unless you want to engineer that part of this with a PLC or microcontroller of some sort, I suggest you contact Aquafinity and find out what the replacement for that CES unit is now. I'd post a link, but my company security platform is not allowing me to get to their site, so they may have been hacked or something.

 

[petersonra]

It is unlikely you will see much difference in efficiency running the motor at full speed versus on a vfd unless the motor is grossly oversized.

You need to filter a certain number of gallons of water. It does not make all that much difference whether you do it at four gpm or five gpm..if you don't at the lower flow rate you just have to run longer.

 

[bellington]

CES is (was) a supplier, recently taken over by a larger company called Aquafinity, but they don't make the VFDs. Their VFDs are Yaskawa and although CES packaged them for their equipment, the drives inside were no different from what Yaskawa sells direct. But that series is no longer supported anyway.

But that Jandy unit only turns the pump on and off, it doesn't have any capability of deciding what speed it should run at, so just having a VFD is not going to accomplish that on its own. That's likely what the CES packaged unit was going to do. So unless you want to engineer that part of this with a PLC or microcontroller of some sort, I suggest you contact Aquafinity and find out what the replacement for that CES unit is now. I'd post a link, but my company security platform is not allowing me to get to their site, so they may have been hacked or something.

Thank you. I was hoping there was a VFD that could be programmed to control the process with possibly filter pressure inputs, or flow rate, that would provide good filtering with minimum power. I certainly don't know enough to engineer it. I will attempt to contact Aquafinity. Thanks again!

 

[kwired]

It is unlikely you will see much difference in efficiency running the motor at full speed versus on a vfd unless the motor is grossly oversized.

You need to filter a certain number of gallons of water. It does not make all that much difference whether you do it at four gpm or five gpm..if you don't at the lower flow rate you just have to run longer.

That was what I was thinking when I asked my questions a couple posts back. Slowing pump down just makes it do same work over more time. Something like pool filter pump that likely runs either constantly or for certain times a day is going to be sized and or timed to do what needs to be done as a general rule. Like you said the only real advantage most the time would be to slow down an oversized pump.

 

[kwired]

Thank you. I was hoping there was a VFD that could be programmed to control the process with possibly filter pressure inputs, or flow rate, that would provide good filtering with minimum power. I certainly don't know enough to engineer it. I will attempt to contact Aquafinity. Thanks again!

Again, if you need to move 25 gallons a minute, it should take X number of watt hours to do so.

If your pump is grossly oversized then slowing it down may save you some energy use as it won't work as hard at the slower speed. But that IMO is poor design unless there actually is a reason you need more flow at certain times, but I don't think that is typical for a pool pump.

Plugged filter actually will lessen the load on a centrifugal pump as it restricts flow (centrifugal pumps are loaded by flow rate and little of the loading is because of pressure) but at same time you get less filtering done. If anything you want pressure sensing to indicate filter is plugged so you can clean filter to get back to design flow/pressure.

 

[Jraef]

The usual application of variable speed in pools and spas is for when there is some operation that needs more flow than others, such as when you need low flow for a long time for filtering, but high flow during sweeping /vacuuming of the pool, or jets in the spa.

 

[bellington]

Thanks to all of you. It is possible that all I need is a soft start function that also serves as a 3 phase switch so I don't run the 5 HP 3 phase motor's 3 wires through the Jandy relays. So, what is a very basic VFD that is highly reliable, that will allow ramp up/down, will allow me to set desired rpm, and use start/stop signal from the Jandy? Thanks again!

 

[ptonsparky]

Thanks to all of you. It is possible that all I need is a soft start function that also serves as a 3 phase switch so I don't run the 5 HP 3 phase motor's 3 wires through the Jandy relays. So, what is a very basic VFD that is highly reliable, that will allow ramp up/down, will allow me to set desired rpm, and use start/stop signal from the Jandy? Thanks again!

Anything that fits your budget. Yaskawa is good, but that is one of many. You will need to know or learn how to interface it with the existing control along with the additional requirements for VFDs.

eta: Your equipment is a good place to start. Can't more than have to replace everything. Is the significant an understanding person?

 

[Mystic Pools]

A pump size is based on the flow rate required for its given application. Whether it's for filtration or for an accessory water feature, spa jets, etc...

A pump curve will give the flow rate at different speeds at a certain foot of head (TDH) for off the shelf VS pumps. Around 50 feet of head is a good benchmark. Single speed pumps will also have different flow rates at certain TDH.

After installing a VFD on your set up, it's up to the contractor to select the speed to work at the required GPM needed. Hopefully they chose the correct pump size and equally important the correct size piping. Without that balance, is all for naught.

I used an Emotron VFD on a commercial project about 12 years ago, for (3) separate filtration pumps. I "dialed in" if you will, the flow rate needed on each set up. I honestly forget how many speeds it offers. I know the owner of the company as they offer other pool related items and have great customer support.

Off the shelf VS pumps generally have 4 speed settings.

 

[garbo]

I would go with a VFD Made in USA. We had hundreds of Danfoss & ABB drives where I retired from. Allen Bradley also had great tech support but have not dealt with them in last 15 years Danfoss had great tech support & ABB techs always gave me a hard time. Just loved ( ya loved to reach out & choke em ) when ABB asked " why do you want to know that". A drive will not maximize flow rate. Most pumps are two pole motors so operate around 3,530 RPM. We had a few pump stations where the maximum speed was set at 70 Hertz but while PM'ing them never saw speed running over 55 Hertz. I'm old school and believe that running motors over rated speed probably shortens motor life. We usually set the minimum speed for pump motors at 20 %. Not sure what type of control you would need for such a pump. Years ago we did it on the cheap by installing a 7 day timer to power a relay. Relay had a speed pot on No & NC contacts. During the weekdays pump would around 55 Hertz and at night & entire weekend around 40 Hertz. We had Johnson control ( JCI ) & Siemens handle all of the controls but not sure if they will sell you or come out for just one drive.

 

[bellington]

Thanks guys. The drive in question is a Yaskawa iQpump Micro Drive. TB1-1 terminal strip has S1 through S7, and an SC. Can those 7 terminals be connected to 7 relays and configured for start/start (S1 and SC), and S2-S7 to SC for various speeds?

 

[ptonsparky]

I don't have the micro drive manual handy but am taking a SEWAG that they are similar to the larger drives.

Thanks guys. The drive in question is a Yaskawa iQpump Micro Drive. TB1-1 terminal strip has S1 through S7, and an SC. Can those 7 terminals be connected to 7 relays and configured for start/start (S1 and SC), and S2-S7 to SC for various speeds?

Yes. Depends on what you set those terminals to do.

 

[ptonsparky]

By default those are set for pressure. It may be a bit more complicated than I suggested.
Do a search.

Basic Programming for Pressure Control with 1000 Series iQpump Drives​