i would like 230VAC 1ph, to drive 380VAC 3ph simonet motor, with vfd
Close
Login to Your Account
Page 1 of 2 12 LastLast
Results 1 to 20 of 26
  1. #1
    Join Date
    Aug 2016
    Country
    GREECE
    Posts
    16
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default i would like 230VAC 1ph, to drive 380VAC 3ph simonet motor, with vfd

    Hi,

    I am wondering for quite some time now, how i will be able to run the simonet motor, of my schaublin/simonet 102 hybrid lathe. The motor is a 380VAC, three phase motor, and it is not possible for me to have 3phase power supply out of the wall. By reading, i understood that using a vfd would be the best way to run the motor, but after contacting some dealers and looking on the web, i cannot say if it is actually possible to do this appliance properly or not.

    Most of the dealers say that it is not possible at all to do this. That i want for example to have a three phase 230VAC motor in order to run it from an one phase 230 power supply through a vfd. I was looking to buy a santerno sinus n, since it is quite affordable and available in the greek market, but i seem to get a reply that this unit wouldn't work with my motor. Some fewer dealers suggest that their units would work, but since most of them suggest that what i am looking for is technically impossible, i ve been kinda left wondering. I also look to some chinese makes, which are quite cheap, and i see in the user manual, that i would need to change the 380V star connection to 220 delta connection. I am not sure how easy it is, if it would work and if by doing this i would alter/decrease the power characteristics of the motor.

    Ideally, i would prefer a method, where the inverter would just provide the power needed from the motor. Kinda plug n play. I don't care for any programming of the inverter unit. I mean, the changing frequency and so changing speed effect, by means of a pot would be nice, but rather than that i don't need something more.

    I have an allen bradley vfd unit, model 1332, CAN. As i understand it is 5KW rated. More than enough for my max 800W motor. But this vfd needs a 3 phase supply. I even tried to input 380VAC, 2phase to it, from a transformer, but the test motor didn't spin..

    I attach a picture with the simonet motor details.

    Would there be an "easy", proper, vfd way, to drive my motor?
    Attached Thumbnails Attached Thumbnails kartelaki_moter_tornou.jpg  

  2. #2
    Join Date
    Jun 2001
    Location
    St Louis
    Posts
    17,384
    Post Thanks / Like
    Likes (Given)
    1591
    Likes (Received)
    2761

    Default

    One question first: Is it possible to wire the motor for 220V instead?

    The best way to answer this is to see a clear picture of the wires in the motor wiring box.

    The reason for this is that it is possible to have a motor made so that by a simple re-connection of wires, it can be run on either 220V or else on 380V. But not all motors are made that way. If the motor can be wired for either voltage, then you will have 6 wires in the wiring box. If not, there may be only 3 wires coming from inside the motor.

  3. #3
    Join Date
    Aug 2016
    Country
    GREECE
    Posts
    16
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    thanks for the reply JST.

    Here is a picture of the wires where you suggest.

    Attachment 234808

    There are 6 wires, plus the ground seven. It is a two speed motor though. I am not sure how this would affect your suggested modification.

    I also measured the resistance between the cables. I have named the cables of the box on the attached photo from 1 to 6. and so:

    1-2 = 28,4 Ohm 2-3 = 28,5 Ohm 1-3 = 28,4 Ohm
    4-5 = 28,3 Ohm 5-6 = 28,4 Ohm 4-6 = 28,5 Ohm

    1-4 = 32,1 Ohm 1-5 = 17,8 Ohm 1-6 = 17,9 Ohm
    2-4 = 17,9 Ohm 2-5 = 17,9 Ohm 2-6 = 32,2 Ohm
    3-4 = 17,8 Ohm 3-5 = 32 Ohm 3-6 = 17,8 Ohm

    I 'm not sure how much these measurements can help.

    These wires are connected to this box here:

    Attachment 234809

    which i think is for speed change. #1, 2 and 3 cables are connected from one side and #4 to 6 are connected from the other. The other cables visible in the latest image attached, lead to a three phase male socket.

    Does it look like it can be easily rewired to 220VAC?

  4. #4
    Join Date
    Aug 2014
    Location
    bainbridge island
    Posts
    940
    Post Thanks / Like
    Likes (Given)
    159
    Likes (Received)
    229

    Default

    your motor has 6 coils of 21 ohms each and to connect that motor for 220 volts you would need to rewire it for delta, which cannot be done without taking the motor apart and bringing out all 12 wires. and you could still preserve the two speed functionality but it would require another pair of contractors also known as 3 pole relays.

    my 2hp 1305 allen bradley 480v vfd runs from a single phase supply just fine, but i cannot remember if it will run from only a 380v single phase supply (voltage may be too low), they are old but still available. and you do not need to look for a 380v vfd, 480v is fine but the voltage it produces is very high and may shorten the life of the motor.

    You can run that motor from a 240v vfd and get up to nameplate torque from it up through 30hz or 1700 rpm. it will at least be usable but won't produce as much torque above that rpm. reprogram the vfd to deliver 240v at 29Hz, not 240/60hz.

    if you buy a 240v vfd and use a buck boost transformer to push the voltage on the single phase input voltage up to its limit, say 260 volts, you can get nameplate torque from your 380v motor all the way up to 34Hz. this will shorten the life of the vfd a bit but the extra torque at 34hz and above might be worth it to you.

    if 1/2th hp is enough you would never know if you only had 220v supplied to the motor instead of the 380 it needs to develop full torque.

  5. #5
    Join Date
    Jul 2014
    Location
    MI USA
    Posts
    800
    Post Thanks / Like
    Likes (Given)
    193
    Likes (Received)
    333

    Default

    Quote Originally Posted by spirous View Post
    Here is a picture of the wires where you suggest.

    Attachment 234808

    Attachment 234809

    There are 6 wires, plus the ground seven. It is a two speed motor though. I am not sure how this would affect your suggested modification.
    The picture links are not working. The nameplate one, in the first post is working, but not the ones in your second post.

    There are a few types of two speed windings. A single winding, reconnected differently for each speed. or a dual winding, where one winding at a time is connected. It's hard to tell what you have without seeing the connection diagram.

    The bad part is, most two speed 6 lead motors are only compatible for a single voltage.

    See if you can get the picture attachments working, post the connection diagram from the motor if possible.

  6. #6
    Join Date
    Aug 2014
    Location
    bainbridge island
    Posts
    940
    Post Thanks / Like
    Likes (Given)
    159
    Likes (Received)
    229

    Default

    Quote Originally Posted by SAF View Post
    There are a few types of two speed windings. A single winding, reconnected differently for each speed.
    I was able to figure it out from his ohms readings. His motor is the type that for high-speed has 3 wires connected and the other three shorted together, and for low speed the 3 wires that are shorted are connected to the line and the other 3 left open.

    probably a lot of work to bring all 12 wires out and connect it for delta, but its definitely not impossible.

  7. #7
    Join Date
    Jun 2001
    Location
    St Louis
    Posts
    17,384
    Post Thanks / Like
    Likes (Given)
    1591
    Likes (Received)
    2761

    Default

    Yes, the question is "how important is this?".

    Motor is evidently a Dahlander type winding, which does not have enough wires coming out of the motor to do the change. One has to take apart the motor, find the wires, and bring them out individually, which is somewhat difficult and technical.

    It may be possible to find a transformer which can make this conversion at a suitable power level. That is simpler, but more expensive.

  8. #8
    Join Date
    Aug 2016
    Country
    GREECE
    Posts
    16
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    Here i attach the pictures again.

    Unfortunately, i do not have a schematic of the motor and by looking online for more info, i couldn't find something helpful. At the front side of the motor, there is a nameplate that says it is a "TV" type motor.

    So to begin with, to make it clear for me, it is not possible to use some type of external converter/inverter to supply to the motor what it asks for, as it stands. Or could a combination of vfd-transformer, or something else might do it?

    If the motor is taken out, the 12 leads found and connected to delta, along with these kind of 3 pole relays, it would be usable with 230Vac input, but it would loose rpm and torque.

    The allen brandley unit i have is 380Vac rated, not 480. 380 volt versions of the 1332 unit, are not covered in the manual, so i guess it must be some sort of special edition. If i had the standard European 3phase supply, this vfd would be great for my motor.. How did you connect 480V one phase to your AB 1305 johansen? Did you use the connectors L2 and L3 as suggested in the manual? When i connected to L2 and L3 the cables out of the 380V transformer, sadly i had 1 to 1,5 volt at the vfd output, where the motor cables are meant to be connected.

    I would like to understand what is technically possible and which option would be more proper/efficient, examining also the costs related to them.

    In the beginning i was thinking to drive the motor/gearbox with an external washing machine motor, but after i realised that i would like to find a better/more proper solution, since this is a nice lathe and i wouldn't want to destroy it by applying weird modifications. Better to set it up properly from the beginning if possible..
    Attached Thumbnails Attached Thumbnails speed_box_simonet.jpg   simonet_wire_box.jpg  

  9. #9
    Join Date
    Jun 2001
    Location
    St Louis
    Posts
    17,384
    Post Thanks / Like
    Likes (Given)
    1591
    Likes (Received)
    2761

    Default

    VFD and transformer would work.

    Possibly best to use a 380V class VFD and use the transformer to supply the proper input. But, it would be best to stay in one speed for the motor, and use the VFD, since some VFDs do not accept switching on their output, according to their manuals.

  10. Likes CalG liked this post
  11. #10
    Join Date
    Aug 2014
    Location
    bainbridge island
    Posts
    940
    Post Thanks / Like
    Likes (Given)
    159
    Likes (Received)
    229

    Default

    Quote Originally Posted by spirous View Post
    If the motor is taken out, the 12 leads found and connected to delta, along with these kind of 3 pole relays, it would be usable with 230Vac input, but it would loose rpm and torque.

    How did you connect 480V one phase to your AB 1305 johansen? Did you use the connectors L2 and L3 as suggested in the manual? When i connected to L2 and L3 the cables out of the 380V transformer, sadly i had 1 to 1,5 volt at the vfd output, where the motor cables are meant to be connected.

    I would like to understand what is technically possible and which option would be more proper/efficient, examining also the costs related to them.
    if you rewire that motor for delta the best option is leave it in the high speed configuration and drive it from a 240v vfd, and it will deliver full torque. while you could add another set of contactors to enable two speed operation, that is a lot of work and there is no point to doing so if you have to have a vfd anyways.

    my ab 1305 doesn't care how dc volts end up on the dc bus. I have wired it for voltage doubling and can run it from a 240v line as well. L1 2 or 3 it doesn't care.

    if your 1332 vfd powered on and didn't fault out for low input voltage or lack of 3 phase (there are ways to fool it) you should be able to get it to work unless its broken.

    if you drive that motor in high speed directly from a 240volt vfd as it is wired now, you'll get full torque up to 30hz, above this speed it will drop to something like 40% of nameplate torque for the same slip. in practice you might be able to get 50-60% of nameplate torque before the motor stalls or the current rises to an unacceptable level.

  12. #11
    Join Date
    Aug 2004
    Location
    San Ramon, CA USA
    Posts
    2,579
    Post Thanks / Like
    Likes (Given)
    23
    Likes (Received)
    561

    Default

    Since you are in Greece and UL listing is not an issue for you, there is a company in the UK that modifies VFDs to take in 240V single phase and put out 415V 3 phase, using what's called a "voltage boost" technology. They don't make the VFDs themselves, they modify VFDs made by other companies. They only sell via eBay now but they sell them up to 10HP (7.5kW). Don't worry about the 415 vs 380V issue, it's all just nominal. You will be able to set the output voltage to exactly 380V if you need to.

    Great deals from Drives Direct Inverters LTD in DIGITAL-24-TO-415-INVERTERS- | eBay Shops

  13. Likes CalG liked this post
  14. #12
    Join Date
    Aug 2016
    Country
    GREECE
    Posts
    16
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    Thank you for your replies,

    The ebay shop suggested looks like it could have exactly what i could use, but for a 2hp unit, i would need to spend more than 500 euros, which kinda exceeds my margin.

    The transformer and 380V vfd, capable of producing three phase out of one phase solution, is something to consider. Although by looking around, i couldn't locate a vfd unit like this. I find single phase 220 to three phase 380 or single phase 220 to three phase 220. Maybe the 380 Volt rated vfd is not advertised as capable of inputing 380 one phase, because this voltage is not available in any type of power supply coming out of a wall. I already did try to supply my vfd with 380 Vac, by a transformer, which the manufacturer informing that it practically produces two phases, because of some square roots of something reason (didn't explain further and probably i wouldn't understand). Anyway this experiment didn't give any usable results. So maybe another vfd could be able to use the power of a transformer like this.

    But something that looks interesting to me at this point, is what johansen states about his usage of the ab unit:
    my ab 1305 doesn't care how dc volts end up on the dc bus. I have wired it for voltage doubling and can run it from a 240v line as well. L1 2 or 3 it doesn't care.
    How this wiring can be done? It sounds kinda simple. Is it? Maybe i could also fool my ab

    I did some test with my vfd and here there are the videos of them.
    For starters, the vfd looks like operating properly under the normal conditions that it is rated for.



    In the second video, i measured the voltage on the vfd output, while powering it with 3 phase 400V. (probably not a good thing that i have it in "run" mode with no load..)



    In this third video, i supplied the vfd with one phase 230 Vac. I do have the "low voltage" indication light on, and i also have a dc fluctuation at the output, going up all the way to 400. I m not sure what this means.. As for AC, it gives about 1,3 volts out.



    In the last video, i connected the motor at the vfd's output, while providing 230 Vac at the input. First of all the motor does not spin at all. Second, i don't have the dc voltage fluctuation that i had with no load connected. And something else that doesn't look good, is a weird sound when it is plugged in mains. Sounds like it is having a bad time instantly..



    In every case, a red LED lamp gets light when power is on, which is indicated as "LED BUS CHARGED".

    It would be quite nice if i could get the motor working with this vfd for starters, even if i wouldn't get the full torque. As far as i understood, using a transformer with this unit, will not do the trick. Unless i didn't connect properly. I connected the transformers output to L2 and L3 on the vfd's terminals.

    The next option, is to find a technician to rewire the motor to delta, keeping only the high speed, and purchasing a 220 one phase to 220 three phase vfd. This is something i did find available, and as far as i understand it will not degrade the torque or speed of the motor. So if using the vfd i have proves to be worthless, this seems like the easiest way to proceed. I 'm already seeing some videos about this procedure and i will have to contact a motor technician to ask about this soon.

  15. #13
    Join Date
    May 2006
    Location
    Seattle
    Posts
    1,696
    Post Thanks / Like
    Likes (Given)
    31
    Likes (Received)
    299

    Default

    I'm guessing your motor is Dahlander wound and as such can only be used at one voltage.

    I have seen a single phase transformer 240->480 feed a VFD which puts out 480 VAC (as mentioned above, you can set it for exact voltage desired) and also a VFD 240 single phase -> 240 3 phase feeding a 3 phase transformer 240->480. Either works. 480 volt VFDs are generally cheaper on ebay, and single phase transformers are almost always cheaper than 3 phase transformers.

  16. #14
    Join Date
    Aug 2014
    Location
    bainbridge island
    Posts
    940
    Post Thanks / Like
    Likes (Given)
    159
    Likes (Received)
    229

    Default

    480vac vfds usually have (2x) 400volts capacitors in series. 380vac vfds might have 600vdc capacitors and this wont work.

    To make a voltage doubler, connect your 240vac line 1 to the midpoint of the 400v capacitors (solder it to the circuit board) the other line to the rectifier input. You will then get 650 to 700 volts on the dc bus. The vfd capacity might only be 30% of nameplate. Yes you can buy some 400v capacitors and some diodes and a box to throw them in, some high voltaage rated wire and run the vfd from the dc directly.

    the derating is because the capacitors are highly stressed with ripple current, so are the diodes but you can connect line 2 to all three input terminals of the vfd so all the diodes are used. you can also add more capacitors or replace them with newer better ones (there have been significant improvements in the last 10 years)
    Last edited by johansen; 08-14-2018 at 03:31 AM.

  17. #15
    Join Date
    Jan 2005
    Location
    The Netherlands
    Posts
    5,491
    Post Thanks / Like
    Likes (Given)
    235
    Likes (Received)
    1298

    Default

    Get another single speed dual voltage motor
    They must be arround used Even in Greece
    You can set the speeds with the VDF
    Easiest way

    Peter

  18. #16
    Join Date
    Aug 2016
    Country
    GREECE
    Posts
    16
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    I have seen a single phase transformer 240->480 feed a VFD which puts out 480 VAC (as mentioned above, you can set it for exact voltage desired) and also a VFD 240 single phase -> 240 3 phase feeding a 3 phase transformer 240->480. Either works. 480 volt VFDs are generally cheaper on ebay, and single phase transformers are almost always cheaper than 3 phase transformers.
    If i would go with a setup like this, why wouldn't i go for a 380V vfd or transformer instead of 480, since the motor is 380?

  19. #17
    Join Date
    Aug 2016
    Country
    GREECE
    Posts
    16
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    Quote Originally Posted by johansen View Post
    480vac vfds usually have (2x) 400volts capacitors in series. 380vac vfds might have 600vdc capacitors and this wont work.

    To make a voltage doubler, connect your 240vac line 1 to the midpoint of the 400v capacitors (solder it to the circuit board) the other line to the rectifier input. You will then get 650 to 700 volts on the dc bus. The vfd capacity might only be 30% of nameplate. Yes you can buy some 400v capacitors and some diodes and a box to throw them in, some high voltaage rated wire and run the vfd from the dc directly.

    the derating is because the capacitors are highly stressed with ripple current, so are the diodes but you can connect line 2 to all three input terminals of the vfd so all the diodes are used. you can also add more capacitors or replace them with newer better ones (there have been significant improvements in the last 10 years)
    If i understand correctly, there is a bank of dc bus capacitors of 8 pieces of 260μF 400WV capacitors. The big ones shown in the photo.
    bus_capacitor_bank.jpg

    On the same board an LED bus charged is placed, which turns on as soon as the capacitors get charged and goes off when there is a voltage drop below about 50 volts, as i read in the manual.
    led_bus_charged.jpg

    By looking below the capacitors pcb, i think that they are four pairs connected in series, which all share a common point between them, as shown in the image below.
    bus_capacitors_common_point.jpg

    Your suggestion would be to connect one of the neutral of the mains to this point and the live to connections L1, L2 and L3?

    What about the 650 to 700 volts that will run through the components as you say? Wouldn't they be damaged of this high voltage, since these capacitors, for example, are rated to be used at maximum 400V?

    About the vfd capacity that would drop to 30%, you mean about the power rating? If so, this wouldn't be a problem since it is rated for 3,7KW and i only need about 800W.

    And what if a voltage doubler were to be made in a separate box? Where would the leads get connected? I already tried to supply 400Vac from a transformer, with no luck..

    Sorry for all of these questions, as you understand i am not really well educated in electronics.
    Maybe it is not a good idea to attempt to do it myself, rather than asking some professional help, but i cannot resist, having this diy disease since years now..

  20. #18
    Join Date
    Aug 2016
    Country
    GREECE
    Posts
    16
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    Quote Originally Posted by Peter from Holland View Post
    Get another single speed dual voltage motor
    They must be arround used Even in Greece
    You can set the speeds with the VDF
    Easiest way

    Peter
    It could be possible to replace completely the motor,
    but i would then need to find one that fits good in the case where it is placed below the gearbox, have an axis that extends the correct amount, in order for the weight to be centered in the casing and have an axis of the correct diameter in order to press in the v-belt disc that gives power to the gearbox, which would have to be taken out of the original motor. I might as well have a look around, but for all of these to apply, it could be that it turns out no being such an easy task.
    simonet_motor.jpg

  21. #19
    Join Date
    Aug 2014
    Location
    bainbridge island
    Posts
    940
    Post Thanks / Like
    Likes (Given)
    159
    Likes (Received)
    229

    Default

    If your vfd did not already work with 400vac, i suspect it is broken but read the manual to see what the undervoltage limit is.

    As for voltage doubleing, yeah you connect line 1 of your 240vac single phase to the midpoint of that capacitor bank and the other line to your input terminals. The diodes alternatively charge half of the bank to 340vdc, then the other half for 700vdc total. Google full wave voltage doubler to see the schematic.

  22. #20
    Join Date
    Aug 2016
    Country
    GREECE
    Posts
    16
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    It's been a while with this project. I was not able to drive the motor with the AB vfd, so i took the whole motor and gearbox assembly to a motor rewiring professional in order to rewire it to for a 3x 220 delta output. Although he is not an expert with lathes he suggests that keeping the low motor speed (1400rpm) would maybe be more appropriate for use with a vfd considering torque outputs. Reading in the forum, my understanding is that i would achieve more desirable results with rewiring to the high speed (2740rpm) and adjusting lower speed by reducing the frequency with the vfd. I do not have experience using lathes, so i am not aware of what kind of needs i will have when i begin working with it. Are there any suggestions about which speed to choose?


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
2