115v motor actuator drive

[thekman]

I need to control a 1/2HP 115v motor...nothing fancy, just want to accel and decel - repeatably. I'm driving a 1500# load with an actuator (Duff Norton SPA6420). I found the perfect drive, a Leeson 175322. I need it in 3 weeks, I can't get it for 10. After scouring the

http://WWW on

and off for 3 days I cannot find a similar model, thought maybe you guys knew of a place that sells a 115v 1/2HP drive. It doesn't even have to be new at this point, as long as it works. Unless I'm missing some obvious alternate solution. My experience with softstarters has been non-repeatability, so I'd rather not go down that road. Would appreciate any help.

 

[itsmoked]

Might I suggest you get a more normal 230V 3ph motor and drive it with a more normal voltage doubling 1ph-input VFD? You could probably do it for half the money and order all of the stuff off-the-shelf in an hour or less. You'd get a lot more control too and at least twice the reliability.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[thekman]

Would love to! Not an option. Plenty of 3ph actuators out there but won't fit in space we have. Looks like we're going to switch to a DC Motor. Kind of hard to believe Leeson is the one and only company that makes such a drive. What's the big deal?

 

[itsmoked]

Single phase drives have a lot of iffy aspects about them that make them harder to successfully implement, they also have operational limitations owing to the single phase motors, hence the higher cost and availability aspects.

Regular VFDs are so competitively crammed with the latest tech and lowest prices, I'd guess they're the best bang-for-the-buck item in all of industry. What you get for the money astounds me every time I crack one open and every time I press "Buy Now". I look at the cast heatsinks and wonder how they can even sell that for the out the door price of the entire drive! Then on top of the casting you have a digital signal processor and all it's ecosystem and probably more than a 100 man-years of engineering stuffed in the firmware. For your application you can get all that in a standard VFD for probably $70 new. Why would one bother with single phase? Other than I guess you, with the size issue.

You know you can buy small 3ph motors with VFDs built into them?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[thekman]

A motor with a built in VFD?? Have not seen that! The drive isn't the space killer, it's the actuator configuration using a 3ph motor...mechanical limits, always mechanical limits!

 

[waross]

The other option is to contact your supplier and ask what is available that will drive your motor.
Possibly a 1 HP drive.
Possibly a 230 Volt drive programmed for 115 Volts.
Possibly a different series drive.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[jraef]

You would not have been able to use that Leeson drive anyway. With single phase motors and VFDs, the motors can ONLY be either Shaded Pole (which don't really need them) and Permanent Split Capacitor (PSC) type. The document you posted clearly states this, I suspect you were not familiar with what that means.

The motors in those actuators appear to be Capacitor Start / Induction Run (CSIR) type. The capacitor would have fried your little VFD, or the VFD would have popped the capacitor; it's a race to failure between the two. Bottom line, you cannot use a VFD on those actuators, they can ONLY be fixed speed.

So now, why is variable speed critical for this? These things don't exactly move fast!


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

 

[waross]

I believe that the motor is a permanent split capacitor motor Jeff.
Link

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[itsmoked]

Some examples of integrated units:

Integrated1

Integrated2

Integrated3

Integrated4


Keith Cress
kcress -

http://www.flaminsystems.com

 

[thekman]

Jraef,
I did notice that right away, and asked the mfr what type of motor it is and he told me PSC. Additionally, it says in the manual that for reversing, the capacitor must "be disconnected". I haven't gotten my hands on it yet, but am pretty sure I can get into it and disconnect it.
I'm sure I'll get yelled at for asking, but can you explain why? I deal with this stuff on a much higher level.
The variable speed will only be used to reduce it to a slower speed before coming to a stop. I pretty much just need a 2-speed, it's not going to vary much more than that, other than the accel.

Keith - thanks!

 

[waross]

I found a diagram online.
It showed three wires. Two windings arranged in a V with the capacitor connected between the ends of the windings.
Label the wire where the two windings connect as "1" and the two ends that are bridged by the capacitor as "2" and "3",
Then applying power between "1" and "2" will give rotation in one direction.
Applying power between "1" and "3" will give rotation in the other direction.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[ScottyUK]

That assumes the windings are equal. That's not always the case, but it's an elegant solution where you can use it.

 

[waross]

In my experience:
A non-reversible PSC motor will have two wires.
A reversible PSC motor with equal windings will have three wires.
A reversbile PSC motor with unequal windings will have four wires.
The diagram that I found for the OP's actuator was the diagram I have seen for a PSC motor with equal windings.
The diagram that I found for the OP's actuator showed three wires.
I have seen a number of small PSC motors using equal windings and three wire reversing.
These are usually fractional HP and small fractions. I have not seen this done with large motors.

This is worry-some;

Additionally, it says in the manual that for reversing, the capacitor must "be disconnected"

A motor runs forward with a capacitor and runs backwards without the capacitor???
Well, maybe.
There are a lot of small motors that use a high resistance start rather than a capacitorwinding to develop a phase shift relative to the running winding to develop starting torque.
I imagine that one of these motors may be loaded up with enough capacity on the run winding to cause it to start in the opposite direction.
Have I ever seen this? No.
I wonder if a winding can be designed to work this way, develop enough starting torque in both directions and withstand continuous running in either direction without overheating.
Maybe....

Additionally, it says in the manual that for reversing, the capacitor must "be disconnected"

Should this read; "Reversing with a VFD"?

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[LionelHutz]

I find it hard to believe that linear actuator 3-phase motors are bigger than their 1-phase counterparts when 3-phase motors are either the same size or smaller for every other application.

If you need fine control, then I think you may want to look at using a linear servomotor.

 

[thekman]

I found another mfr of singlephase motor drives....they seem much more informed and have more reasonable current ratings...just wanted to share..

http://anaconsystems.com/single-phase/

 

[jraef]

Just so you know, Anacon is not the actual mfr of those drives, they are made by another company in the UK called Invertek. You can also buy those drives from another US supplier named Bardac. But truth be told, the VFD for a single phase motor is likely going to cost you MORE than a VFD for an equivalent 3 phase motor, just because of shear volume of the available market.


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

 

[thekman]

Ya, I've got the Invertek data sheet, Anacon is a vendor here in Texas. Thanks, I'll definitely look at those too.

 

[btrueblood]

I've built and run a lot of equipment that use 3-phase motors, controlled with a VFD running on 115v single phase. So, if you can swap out that motor for a real one, this drive might work:

https://www.automationdirect.com/ad...l)/GS1_Drive_Units_(120_-z-_230_VAC)/GS1-10P5

Fuji electric makes similar drives, for a bit more money, and is the more usual brand I look for.