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Meidinger Pipe Organ Blower Hook up

Meidinger Pipe Organ Blower Hook up

Meidinger Pipe Organ Blower Hook up

(OP)
Greetings!

I have a Swiss built Meidinger blower designed for use in a pipe organ. It came set up with a 80mf capacitor to facilitate operation on 110 VAC SINGLE PHASE supply even though this is technically a six wire three phase motor.
The boiler plate indicates 110 VAC with a symbol like an inverted letter "T" which I am interpreting to mean that the winding should be placed into STAR formation. When I opened the terminal box it appears to have actually been set up in DELTA configuration with the capacitor between L1 and the third phase winding to create the necessary bias for operation from a single phase supply at 110VAC. The motor actually starts and runs in this configuration but I am not sure if it is correct or safe given that the nameplate appears to call for STAR config.

I would like to do away with the capacitor and run this from a VFD That provides three actual phases. I would like to power the input of the VFD from 120VAC single phase. Is this possible given the spec of the motor? How should this motor be connected? STAR or DELTA? and what supply voltage should be supplied from the VFD output? Can this be run on 240VAC? Any recommendations as to specific VFD and other needed equipment would be most appreciated. More specs below:

Meidinger blower Model MFO 1202 NIKX 33 Uv
H.P. 1/2
Period 60Hz
3360 RPM
110 VAC STAR?
5 amp

Checking with an OHM meter shows each individual winding to have impedance of 1.8 ohm end to end or 3.6 ohm per phase in STAR formation as there are always 2 windings in series.

Many thanks
Allen

RE: Meidinger Pipe Organ Blower Hook up

Hi Allen,

Any chance of a photo of the maker's plate on the motor? You can upload pictures using the green square blobs between the bullet point drop-down and the smiley face.

If you use a VFD then in principle you could program it to suit the motor provided the motor requires a lower voltage than the VFD is capable of producing (i.e. you can "turn the VFD down" a bit).

RE: Meidinger Pipe Organ Blower Hook up

(OP)

RE: Meidinger Pipe Organ Blower Hook up

That looks like a 1 (one) signifying single phase.
110 Volts x 5 Amps = 550 VA. That's about right for a 0.5 HP motor.
You won't find much three phase power at 110 Volts, 60 Hertz.
Measure the current. It it takes close to 5 Amps it is probably OK.

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

RE: Meidinger Pipe Organ Blower Hook up

I thought that was a "1" as well, but look above it on the plate, there are other 1s depicted and they look different.

I think this is what that symbol might mean:



Or... maybe this...
http://www.organsupply.com/assets/Help-Center-Inst...



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

RE: Meidinger Pipe Organ Blower Hook up

Meidinger are still in business, it can't do any harm to ask if they have a datasheet on their old products. I can't find anything close to it on the current website, but they claim to have data on all their older types. There's an online contact form, or perhaps email them that photo.

https://www.meidinger.ch/en/contact/

info@meidinger.ch

RE: Meidinger Pipe Organ Blower Hook up

I'm skeptical the inverted "T" represents information related to the motor winding connection.
It does not appear to be an International Electrotechnical Commission symbol after searching through IEC 60034-8 (Edition 3.1 2014-03)

The stamp that made the mark is also different than the letter T stamped in the top line of the motor name plate.

The URL jraef has posted above pretty much answers the OP's question.

Remove the capacitor and hook it up as shown in the PDF above for a 208-240 three phase connection.

It could be making music tonight!

John

RE: Meidinger Pipe Organ Blower Hook up

Almost. The OP wants to power from 120 VAC, so the 108 Volt, delta connection would be the one to use.
If the motor current (as reported by the VFD) is a little too high with the motor configured for 108 Volts, the motor is also rated for 208-240 VAC so the low voltage connection will be suitable for configuration as 120 VAC. That should drop the motor current a little if required.

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

RE: Meidinger Pipe Organ Blower Hook up

(OP)
Hello All,
Thanks for the replies. Bill to clarify your response and make sure I am understanding all of this correctly. I plan to run this from a VFD that accepts power from a 120V line. Even so, it seems all the VFD's I can find seem to output in 240VAC regardless of the 120V input voltage. Does this mean that I should try the motor first in the 208-240V STAR configuration in the diagram omitting the capacitor? I doubt I will be able to find a VFD that outputs in 120V three phase so the winding will have to be able to accept 240V it seems. Wouldn't the high voltage STAR config be the safe zone for such an experiment. Please forgive my ignorance in all of this as I don't have any experience with the implementation of a VFD. Is there any other equipment recommended to protect the motor like output filters or something? I understand that these VFD's can be a little "spiky" on the output side. This is an older motor that I am sure was never designed specifically with a VFD in mind and I want to protect it if I can. It is very difficult to find a motor shop that will rewind these if something happens.

Allen

RE: Meidinger Pipe Organ Blower Hook up

A VFD can always be programmed to put out any voltage LOWER than the line voltage, just not higher. A VFD converts the incoming AC to DC then recreates an output that the motor "sees" as AC, but it is wholly artificial, so it can be whatever you tell it to be. So yes, you can tell a VFD to put out 110VAC 3 phase.

Now whether or not that motor is really 110V 3 phase is another question. There is no such thing as 110V 3 phase anywhere, so I find it hard to believe anyone would have made a motor like that.


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

RE: Meidinger Pipe Organ Blower Hook up

If it had been intended to install the organ on a submarine it would be appropriate to have a 110V 3-phase motor. Otherwise not likely.

RE: Meidinger Pipe Organ Blower Hook up

Despite the rating the VFD can not output more voltage than the input.
You can configure the VFD to output the voltage that you need.
If the motor is rated for 240 Volts in star then each winding should be good for up to 139 Volts in delta.
It should be safe to run at 120 Volts despite the 108 Volt rating.
You bring up a good point about VFDs and older motors.
One way to mitigate this is to use a transformer to change the output voltage. 1:2 or 120:240 Volts may work.
Jeff is the one to take it from here. He is much more familiar with filtering methods for VFD outputs.

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

RE: Meidinger Pipe Organ Blower Hook up

Quote:

If it had been intended to install the organ on a submarine it would be appropriate to have a 110V 3-phase motor. Otherwise not likely.

Or 40's era rail cars.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Meidinger Pipe Organ Blower Hook up

I want to know how a VFD with 320V on its DC link could possibly ever put out 120V? I don't believe the ON/OFF pwm can come close to doing that. All it can put out is 0V or 320V. The hideous output waveform may end up delivering something (under the V/Hz curve) to the confused motor iron that leaves it thinking it was seeing something less than 320V but it's not. I don't believe there's any output sensors in drives or even capable of sorting out all the gibberish leaving the drive to come up with a guess about the average voltage let alone someway to control it.

Any motor you're trying to drive will see spikes of at least what the DC link is charged to. If you don't want the windings thrashed with those level of spikes you will need to use an interposed transformer to numerically reduce the 320V spikes to what a 110V would expect. (~155V)

Keith Cress
kcress - http://www.flaminsystems.com

RE: Meidinger Pipe Organ Blower Hook up

He's inputting 120 Volts Keith. He will be seeing 170 Volt peaks.
Keith is correct that the instantaneous Volts out will be either the DC buss voltage or zero volts.
However the effect of the Pulse Width Modulation combined with the VFD source impedance and the motor resistance and impedance will result in an adjustable effective voltage to the motor.
The Pulse Width Modulation will produce an effective sine wave at any frequency and effective voltage within its ratings.

Back in the early 80's I ran across a small portable generator (maybe 3 KVA) that was 110 Volts, three phase delta. That's the only time I have seen it.

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

RE: Meidinger Pipe Organ Blower Hook up

First, a VFD that accepts 120V input will have a voltage doubler on the rectifier so that the DC bus voltage becomes 338VDC, facilitating an output of up to 230VAC PWM.

Second, the output RMS voltage is ALWAYS being artificially manipulated by the drive. Think about it; if a 230V VFD is maintaining a constant V/Hz ratio for a 60Hz motor, what’s the V at 30Hz? All you need do in the VFD programming is tell it that you want 110V at 60Hz and the algorithm calculates the Necessary PWM pattern to deliver that.

One thing that is true is that the peaks of each DC pulse in the PWM output will remain at the DC bus level, in this case 338V. That can sometimes be problematic for older motors that were not built to be run from inverters and made with very low insulation voltage. But that tends to not be an issue on motors designed for 230V.


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

RE: Meidinger Pipe Organ Blower Hook up

Thanks Jeff.

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

RE: Meidinger Pipe Organ Blower Hook up

Thanks Jeff that was my point exactly as I'm a bit concerned about this ancient motor's insulation. I'd use a transformer at the very least.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Meidinger Pipe Organ Blower Hook up

(OP)
Does the suggested "transformer" refer to a device called a "load line reactor" perhaps of the high frequency compensated variety? Is this what is meant by "transformer". I ask out of ignorance because I don't know what all these names for things actually mean.

RE: Meidinger Pipe Organ Blower Hook up

Nope allencga.

A transformer actually changes the voltage by stepping (transforming) it up or down as desired.

A reactor removes or reduces fast current changes. They use them to help prevent VFD electrical noise from going back to the source. They help the VFD rectifiers by stretching out the conduction angles reducing the current peaks the rectifiers see. They reduce what the rest of your power systems sees when a VFD is on line. They can protect the VFD from spikes coming in from the supply. Someone may have more VFD application uses too.

Reactors do not change the voltage other than causing some amount of loss, a few volts - they tend to get quite warm.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Meidinger Pipe Organ Blower Hook up

And the transformer windings act as a reactor.
At one plant I was at, there were a series of SAGD well pads. Each well pad had a large VFD driving a submersible pump down the hole. With the long lead lengths harmonic overvoltages were a serious concern.
Some pads had filters which included reactors.
Some pads had transformers to match the supply voltage (480 Volts) to the pump voltages (4160 volts).
None of the pads had both a filter and a reactor.

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

RE: Meidinger Pipe Organ Blower Hook up

(OP)
I would probably like to use reactors going in and out with perhaps high frequency compensation on the output side reactor. Is there a recommended supplier for these?

RE: Meidinger Pipe Organ Blower Hook up

(OP)
This has been a fascinating and informative discussion and I appreciate the input from everyone.
There is yet another point of interest here that I cannot get my head around.

This truly seems to be a three phase motor with three independent identifiable windings terminating in 6 wires in the terminal box and the windings do not seem interconnected in any way. This is as expected.

I am familiar with the trick of providing TWO AC supply lines of 230V each offset one from the other by 180 electrical degress augmented by a capacitor to bias one of the hot legs to create a "third phase" of sorts. These motors run ok if a little hot in this config due to unavoidable imbalance because of the sign waves not being equidistantly phased.

This motor on the other hand seems purposely designated for operation on 110v meaning literally one hot leg carrying the 110V sign wave, a neutral, and a capacitor and it really does start and run this way. How is this even possible? How is it coming up with three phase functionality having only one hot leg, a neutral and a single capacitor? I would be interesting to know what is going on here.

Incidentally, the inverted "T" from earlier in this thread does appear in a table of electrical symbols and is associated with a special transformer connection featuring center tapping of windings. This is known as a "Scott" transformer and was apparently designed to make old 2 phase motors operable on three phase power systems. I am sure this method languishes in obsolescence by now and doesn't seem applicable to this situation.

Anyway, what's up with this whole set up being operable as it is with a neutral and only one hot leg?

RE: Meidinger Pipe Organ Blower Hook up

First do a little reading.
Try the Cowern Papers.
Cowern papers
Perhaps someone else can suggest a good basic text online for three phase systems and vector relationships.
By the way, the capacitor seldom results in a 90 degree phase shift, and the phase shift angle will vary as the value of the capacitor varies.
Once the motor spins up, the back EMF pulls the angle close to 90 degrees for a single phase motor and 120 degrees for a three phase motor.
The motors run hot because one or two phase windings are doing the work of three phase windings.
The winding powered by the capacitor may not be doing its full share.
It depends.

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

RE: Meidinger Pipe Organ Blower Hook up

Century had a line of single phase motors with poly-phase lap windings in them.
It's been too long ago to remember specifically what models they were.
I kind of remember they were in cast iron frame configurations.

I agree with Bill. One needs to read up on the subject of motors to understand what makes them run.

If you had the means... one could take a modest size 3-phase motor out of a box,
(say 1 HP or below for purposes of experimentation) and by connecting a motor run capacitor in the proper circuit location,
make it run upon applying a source of single phase alternating current.

It'd be called a Permanent Split-Capacitor Run motor at that point.
PSC motors don't have a lot of locked-rotor torque but they are generally found in fan and blower applications
which correlates with what this pipe organ motor appears to be.

As for that upside down T on the name plate? I do not know what it is intended to represent.
I'll express again it's doubtful it means anything related to how the motor is connected.

(The symbol could be construed as a split winding I guess... for the vertical line is splitting
the horizontal line in half....) Again, I doubt this guess even.

What I want to know is... when you get this thing up and running... after all this discussion...
what URL do we go to... to hear the music?

John ; )

RE: Meidinger Pipe Organ Blower Hook up

And what sort of organ is it? Tracker? Or something else? Is the tuning Baroque, Classical, mean tone temperament, or something else? How many speaking ranks and what are their voices? What is their disposition? How many manuals? Pedal board or not? What wind pressure does it operate under? Existing instrument or new opus? Who is/was the builder?

The blower size suggests more of a chamber, or chapel, or residence organ rather than something in a church sanctuary of any significant size...

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: Meidinger Pipe Organ Blower Hook up

The Op's going to have a research project on his hands to answer the additional questions
posed by crshears. (All great questions by the way ; )

For even more insight or "clouding" into this conversation... another thought comes to mind.
(Not for purposes of hi-jacking the thread.)

The organ motor in topic could also be "loosely" described as a rotary phase converter.

Don't have a lot of time to reference the perfect description because it will interrupt my Cabin Fever,
but if one wants to spend all day surfing the U.S. Patent site, you will eventually find a phase converter
circuit configured similar to the motor in discussion complete, with an authentic description of how it "works".

Here's one URL to get you started: https://patents.google.com/patent/US4792740?oq=rot...

Opinion: A while back, I remember mentioning that an electric motor today has become
a perfectly designed item, and that the bulk of interest or focus now is in all the complex
electronics that's been invented to run them.

Before the advent of electronic control there were lots of creative [ingenious] ways of powering an insulated conductor
wrapped around a ferrous metal to achieve a mechanical rotation of a member.
Many of these methods fall into the category of lost or forgotten art.

An example of another motor that can rack the brain of the brilliant is the Split-Series D.C. Motor.
It's a reversible direct current motor with 3 exposed connection leads that when powered,
only one field pole is energized.

John

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