Scully owners, what kind of motors do you have?

[Virtalahde]

I'm just interested in what you're using. Mine is a synchronous motor (dual hysteresis motor) from Electronic Specialty Co. 9/1800 RPM, 115vac/60Hz, 0.95A. Driven by a Siemens Micromaster 410.

The system came with a 230-115vac step-down transformer, huge beast. Since I'm stripping this thing down anyway and the only part that needs 115vac/60Hz is the motor, can't I just do the conversion with the inverter and skip using the transformer altogether?

[audadvnc]

Bodine 1/4 hp motor:

[skyonion]

I remember my motor is a 1800 rpm synchronous hysteresis motor, I don't have more details. Unfortunately it has to be removed to see the information plate on it's side, and I didn't take a good picture before I installed it.

I'm not sure what you mean about driving the motor off of the inverter. One thought I had is that synchronous motors want a true sine wave at 60hz to lock into their stated RPM, and many inverters don't generate a true sine wave. So that may be why the motor is driven off of a huge transformer.

[Virtalahde]

No, there was a step-down transformer before the inverter and the Siemens Micromaster was hooked up straight to the motor (well, there was a simple 1st order L filter after it). I believe that at least with the Siemens inverters, they don't even like anything between the outputs and the motor.

http://www.lencoheaven.net/forum/index.php?topic=11817.0
http://www.lencoheaven.net/forum/index.php?topic=11817.0
http://www.tnt-audio.com/accessories/siemens_micromaster_420_e.html

Here's something I've been reading about those inverters.

Next Tuesday I'm taking my motor + gearbox to a good motor repair shop for general checking of the condition.

[dubcutter89]

Haven't read all posts, but I have worked with a Siemens-Micromaster on a Presto 8D... (member Bancho knows more about)
The thing is that most(all) inverters are made for 3 phase motors, but most lathes run from 1 phase with add of cap.
ANother thing is that those units are very clever, sensing currents etc. so it's not so easy to use them for other (wrong) applications such as 1 phase for motor and the other 2 left open...
Normally you can set the voltage to 110V and don't need a transformer...
Look if your motor is a 3 phase motor that is wired to work from one - asfaik the lyrecs can wired for 3 phase operation...


Lukas

[Virtalahde]

This thing seems to be a 3-phase motor. No caps, and was hooked up like a 3-phase motor would be.

[bancho]

I use bodine 1/4 hp Bodine motor just as in the picture of audadvnc. I have Siemens microcontroller 420. First i thought the motor is 3 phase also but then I found out it has actually 4 wires... and it is 1 phase with cap. so I just coupled two wires and made it "look like" 3 phase and siemens "didn't notice". I just followed the setup instructions and it works. The only thing is the motor is getting quite hot while running. I asked a friend who has more knowledge in all this electro stuff and he said he would ground everything he could on this lathe because of tricking the microcontroller and the risk of burning the motor and electrical shock. So I did it.
He sugested me to use another (real 3 phase) motor. There should be no problem in pitch of the platter because there is the screw and the clutch which absorb all the speed irregularities... I have this in mind but didn't try it.
I hope this helps (at least just a bit)

[leo gonzalez]

I He sugested me to use another (real 3 phase) motor. There should be no problem in pitch of the platter because there is the screw and the clutch which absorb all the speed irregularities... I have this in mind but didn't try it.
I hope this helps (at least just a bit)

that's interesting. i think there are tachometers that you hold on the output shaft while it spins to measure the speed.
in my case im having a hard time figuring out how the gearbox behaves with coupled to the 1800 motor.

I have a spare arcturus motor very similar to the others posted but with a TURNER CO 1/4 hp 1800rpm 5A single phase motor.
Its hard to tell with this configuration of motor and gearbox what is the wow/flutter source.

a lovejoy coupler between the motor and the gearbox could work.

Im actually ordering an olham coupler to deal with slight shaft misalignment.

Virtalahde: you should be ok with a 1800 1/4 "48Y" 120 V
look for motors withing the 48Y frame size.

[leo gonzalez]

asfaik the lyrecs can wired for 3 phase operation...


Lukas

I don't know about that....

there are 2 windings per speed... not 3.

unless im missing something i dont know how you would feed 3 phases into a lyrec

[dubcutter89]

with the phase shifter (capacitor) you are somehow trying to make a "3 phase system"...
i guess it works good enough for everyone
and i guess there are not that many cutting rooms having a 3 phase power plug in the wall...
but you are right the lyrec is a bit strange 3 phase motor with only 2 coils - don't know the exact physical layout
that would be needed to see the realtion between electrical phase and mechanical phase (don't know if this are the correct terms in tech. english...)

but since you're asking:

[leo gonzalez]

hehe, im not asking...

what i'd like to know about the lyrec is if there is a member here that has ran them feeding the 2 winding from a regular 3 phase feed and if it does run quieter than with the cap cheat..

even though.. this would make more sense towards the direction of this thread, which is if 3 phase motors can produce a more constant speed and run quieter than a single phase one.

by the way, that schematic does not prove your point... it's not telling you that the feed is 3 phase, hehe.

L.

[flozki]

with regular 3 phase, well actually 2 phases and all voltages the same the the motor would run perfect.
but the voltage is way to high. so best way is to use a frequency converter. with variable voltage output.
if both voltages are equal and the windings the same it will run super quiet.

[leo gonzalez]

but before the micromaster, shouldn't this way of creating 2-phase be better than with the cap-cheat:

http://en.wikipedia.org/wiki/Split-phase_electric_power

here in the states you can add a 240V breaker to the electric panel and then come down from it to a split phase trafo.
should work better than a cap for this application in terms of synching the voltage and the current flow of the 2 phases?

anyways.. here's the lyrec monopolizing threads again...

back to regular gearbox-motor oldies!