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Can it be rewired to be 2 speed
- Thread starter pegitt
- Start date
Hi,
Modifying your current 1ph motor for 2 speed operation is not very practical. There are some options however;
1). Change out your current motor to one designed for 2-speed operation and modify your existing controls
2). Install a gearbox.
3). Install a drive and replace your current motor with a 3-ph.
Since most all (if not all) 240V drives these days will except a 1-ph input and deliver a 3-ph output. I think I would opt for #3. That way you could "tinker" around and find whatever speeds you require.
There might be some other ways to go but, those are the three that come to mind right now.
Take it easy
Ed
Modifying your current 1ph motor for 2 speed operation is not very practical. There are some options however;
1). Change out your current motor to one designed for 2-speed operation and modify your existing controls
2). Install a gearbox.
3). Install a drive and replace your current motor with a 3-ph.
Since most all (if not all) 240V drives these days will except a 1-ph input and deliver a 3-ph output. I think I would opt for #3. That way you could "tinker" around and find whatever speeds you require.
There might be some other ways to go but, those are the three that come to mind right now.
Take it easy
Ed
- Thread starter
- #4
Hay52 is is right that if it is a permanent split capacitor motor you can lower the RPM. If the motor has a centrifugal switch you wont be able too since the mechanism will think the motor is slowing and will try to power the start windings again.
Take a look at these options... (This is just an example)
Take a look at these options... (This is just an example)
Woops.
This link should work...notice the 2 speed models...
This link should work...notice the 2 speed models...
No, don't do that. Reducing the voltage with a variac or any solid state "dimmer" will reduce the torque, which may cause the load to slow down, but it will not reduce the "power" if the load is the same. So the motor will draw more current attempting to maintain speed and overload. That method only works on low torque shaded pole motors such as ceiling fans, but are unlikely to be used on any pump applications.
"Venditori de oleum-vipera non vigere excordis populi"
"Venditori de oleum-vipera non vigere excordis populi"
Not to be too negative, but rewinding that motor would be far more expensive than replacing it. And either way, you will need a control system capable of deciding which speed to run, and switching around the separate windings to change it. If this is, as I suspect, a spa pump as indicated in this link , your existing spa controller will not have that capability. If you look down on that catalog to the next version, the 440 Series, it IS a 2 speed motor, just for the purpose you mentioned. But it still must be coordinated with a controller made for that, and mentions that in the catalog.
Find out what kind of motor it is. If it is a PSC (Permanent Split Capacitor) design, there are speed controllers that will work. If it is any type that has an external capacitor on it there is no way to reduce speed. You must either replace it with a 2 speed version as he showed, or reduce the speed externally as aolalde said. The catalog information does not indicate what type it is, and that box on top of it could be big enough to hold external capacitors. Open it up and take a look. If you don't know what a capacitpor looks like, look at the label for any designations that include the term "mf" (for microfarads). That would indicate it is a capacitor. if there is nothing but wires insidethere, it may be a PSC motor and you could put a VFD on it and use an external pot to change speed.
If all this sounds too complicated for you, live with it like it is.
"Venditori de oleum-vipera non vigere excordis populi"
Find out what kind of motor it is. If it is a PSC (Permanent Split Capacitor) design, there are speed controllers that will work. If it is any type that has an external capacitor on it there is no way to reduce speed. You must either replace it with a 2 speed version as he showed, or reduce the speed externally as aolalde said. The catalog information does not indicate what type it is, and that box on top of it could be big enough to hold external capacitors. Open it up and take a look. If you don't know what a capacitpor looks like, look at the label for any designations that include the term "mf" (for microfarads). That would indicate it is a capacitor. if there is nothing but wires insidethere, it may be a PSC motor and you could put a VFD on it and use an external pot to change speed.
If all this sounds too complicated for you, live with it like it is.
"Venditori de oleum-vipera non vigere excordis populi"
I know it is a bit "Mickey Mouse" but could you use a second smaller motor to drive the same shaft through a suitable pulley reduction ?
The idea is that the big motor can run at normal full speed, and the small motor drive the load at reduced speed. When running at normal speed the small motor would be significantly overspeeded, but that might not be a serious issue. I suppose it depends on how far apart the two required speeds need to be.
I realise this is not a terribly brilliant idea, but it may still be practical and workable in some situations with a bit of care.
The idea is that the big motor can run at normal full speed, and the small motor drive the load at reduced speed. When running at normal speed the small motor would be significantly overspeeded, but that might not be a serious issue. I suppose it depends on how far apart the two required speeds need to be.
I realise this is not a terribly brilliant idea, but it may still be practical and workable in some situations with a bit of care.
I doubt it. That looks to be a close coupled pump for a spa. I have one like it, but mine is the 2 speed version. The low speed is used twice per day to run water through the filter when not in use. But when it is play time, the high speed provides the jet pressure and required suction for the aerator venturis.
Another aspect of what I said about your existing controls is the issue of "flick a switch" as you put it. That is a tricky prospect in spa controls. There needs to be carefull attention paid to human safety when dealing with switches and being wet.
"Venditori de oleum-vipera non vigere excordis populi"
Another aspect of what I said about your existing controls is the issue of "flick a switch" as you put it. That is a tricky prospect in spa controls. There needs to be carefull attention paid to human safety when dealing with switches and being wet.
"Venditori de oleum-vipera non vigere excordis populi"
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