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School me on frequency convertors and VSDs please


moparmuppet

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 Who are the clever electrical boffins on here? There was a tyre machine topic 3 years ago but looks like the O.P. has left our fine company.  I have an 2nd hand 3 phase tyre machine on the way and a single phase supply.  Can anyone school me on 230V single phase  to 3 ph 400V thingeys and terminology. The 3 phase motor is 0.75 kW.  I have 230v 15Amps available. For a tyre machine that you would want to start and stop instantly ( and reverse on its rotary switch) I guess I want a frequency converter? not a VSD?  Guess they are cheaper too?  Or use a VSD and make the starting and stopping ramps as vertical as allowed? What is the recomended way of sizing the units for fairly high load instant running applications like the tyre machine?   @00quattro00 does Mum still work for ABB?  I also have a work card that worked bloody well last time I bought at IDEAL electrical. Depending on the neds I figure a brand name sourced from this once-great nation will be a better bet than one from the buttplug builders. As you can see I know nothing.

School me please. Hugs, Vaughan.

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a single phase 230v input  to  3 phase output VSD will work fine for what you  need providing that the 3 phase motor can be wired in 230v star configuration( some motors are wired for 400v only) a 1.5kw rated vsd should handle the 0.75kw load with lots of starts and stops fine,  but for such a small motor it would be worth pricing up a single phase one 

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I'm no expert but I run a few of my machines on VSD's, as above you need to check the motor can be wired for both delta(400v) and star (230V), most modern stuff is and you can see it on the name plate, like this pic below.

All my VSD's i've got from trademe, mine are all 2.2kw so popular size and harder to find, but you see the smaller ones pop up on trademe from time to time for cheap($100ish), having a full ramp and setting up a reverse switch should work how you want, but i'd oversize the unit a little because start-up torque could draw higher current than nameplate suggests and I never want my electrical equipment sitting on the limit.

Depends on how the machine is setup but have you considered swapping the motor out for a single phase? the second hand sub 1kw motors don't seem to hold much value...

Three-phase-induction-motor-nameplate-As-seen-in-delta-connection-it-uses-240V-37-A.jpg

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Thanks @vk327  @drftnmazI was  thinking about all the control side and wanting to reverse the motor too, thinking it might have been in the too hard basket with single phase. I will ring the old agents and see if they have any info. You mention star,  most of these 3 phase tyre machines are 2 speed turntables and assume the first 1/2 press of the pedal runs star, a full press will go delta so I am guessing that means the motor will be happy running star all day without overheating. 

 Drftnmaz. Looking at your motor plate it is 220V on delta and 380 on star?  not the other way round as you mention at the top of your reply? Does that mean it is rated for 3 x 220v in  Delta   Are your machines running 220 or 380? Hooked up star or delta?  Do the 220V x 1 input VSDs output 3 x 220v or 3 x 380v?  Just trying to get my head around it all. I will be home mid weekend and will look at the motor plate.  Cheers, Vaughan.

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2 minutes ago, moparmuppet said:

Thanks @vk327  @drftnmazI was  thinking about all the control side and wanting to reverse the motor too, thinking it might have been in the too hard basket with single phase. I will ring the old agents and see if they have any info. You mention star,  most of these 3 phase tyre machines are 2 speed turntables and assume the first 1/2 press of the pedal runs star, a full press will go delta so I am guessing that means the motor will be happy running star all day without overheating. 

 Drftnmaz. Looking at your motor plate it is 220V on delta and 380 on star?  not the other way round as you mention at the top of your reply? Does that mean it is rated for 3 x 220v in  Delta   Are your machines running 220 or 380? Hooked up star or delta?  Do the 220V x 1 input VSDs output 3 x 220v or 3 x 380v?  Just trying to get my head around it all. I will be home mid weekend and will look at the motor plate.  Cheers, Vaughan.

I reckon Drftnmaz just made an error. The Delta option will always be the lowest voltage the motor will run on.

I am not clued up on how the speed control would work for your current setup. But I would imagine that if your motor was 380v delta and you wired a 380v 3PH supply to it in Star, it would run slower.... but I'm no electrologist.

I've looked into VFDs to get my head around it for a big motor I am installing on my lathe.

Most VSD/VFD will be 220v 1PH in and 220v 3ph out. If your motor plate has a 220v Delta(the triangle) option, you can use that kind of VSD/VFD. These are the reasonably inexpensive ones.

If the Delta option on your motor plate says 380v, then the Star(upside down Y) will be ~600v, you cannot run it on the above type VFD. But you can get a VFD/VSD that does 220v 1PH in and 380v 3PH out, but they cost much more and they are not nearly as common.

I have ordered a 7.5KW VFD from AliExpress, to run a 5.5KW 380v 3PH(Delta) Motor. The VFD was ~$600. It's on longtime shipping. I ordered it at the end of April... it's been "on a plane" since June 23rd. Still got another month left on the order guarantee thingo. Hopefully I have not wasted my money.

If you don't want to wait a million years... There is a VFD guy on Trademe. I'm pretty sure he is just reselling the Aliexpress VFDs and he has a hefty markup. Last time I looked he did have some of the 220v 1PH to 380v 3PH VFD.  

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Cheers @Adoom That plane must be getting low on fuel. If it runs out it will be stuck up there forever.  If it turns up I would be keen on your review of it (Mauser lathe right?)

Just seen this on T.M. but it sure seems arse about face with the wiring. https://www.trademe.co.nz/Browse/Listing.aspx?id=2725788388   230 1 phase to the motor and converter out the other side?  I just want a VFD with a PDL plug on the output I would think.

Do you have a link to the VFD you allegedly bought?  Thanks for clearing some of the muddle up. Seems like if I am rated 230V Delta it shouldnt be too hard. (easier than getting a single phase and making it reverse. Gonna email the agents as well though. Nothing like doing it once, poorly eh?

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59 minutes ago, moparmuppet said:

Cheers @Adoom That plane must be getting low on fuel. If it runs out it will be stuck up there forever.  If it turns up I would be keen on your review of it (Mauser lathe right?)

Just seen this on T.M. but it sure seems arse about face with the wiring. https://www.trademe.co.nz/Browse/Listing.aspx?id=2725788388   230 1 phase to the motor and converter out the other side?  I just want a VFD with a PDL plug on the output I would think.

Do you have a link to the VFD you allegedly bought?  Thanks for clearing some of the muddle up. Seems like if I am rated 230V Delta it shouldnt be too hard. (easier than getting a single phase and making it reverse. Gonna email the agents as well though. Nothing like doing it once, poorly eh?

Meuser.

"Mauser" is a... gun?

That mystery white box is probably just full of big capacitors. An oldschool way  to run a 3ph motor on 1ph. I believe there are downsides to doing it that way.  But that is the same trademe seller I mentioned that has the VFDs too.

This is what I ordered. The 7.5KW option. https://www.aliexpress.com/item/4000927690757.html?spm=a2g0s.9042311.0.0.48194c4dFSZbhp

 

Remember, I'm not an electrologist, this is just from the research I did before ordering my VFD.

 

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Gidday Yowzer. I just got a hoist, new, single phase. 2.2kW,( 4200kg) so about 3 times the size of the tyre machine motor . I understand there will be a bit of torque loss with a VFD converter but I am hoping it takes less ergs to turn a tyre than to lift a yank tank. They did build this machine as 230V 1 ph but who knows what gearing differences to achieve it etc. Bodging it myself with a motor from under someones bench would probably end up with a sub-optimal result so if I went single phase it would need to be as per factory, especially with your input there. kinda has me leaning toward VFD.  Cheers

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Yea sorry, mistype on the star/delta thing...
Most VSD will go from 1ph 230v to 3ph 230V, If you want 400V then it will also need a step-up transformer, but going up voltage and to 3ph would cause massive current draws due to losses in the conversion and likely max out your available shed wiring.

So check if your motor has Delta  230V option and if so then you can wire it to suit and run off a normal 230v vsd, most vsd's have input triggers, IE my Picodrive unit has option for external reverse trigger (but i've never used it) however I have wired in a external potentiometer so I can change speed on demand form the front of the machine while working, it also has current limits and start frequency and ramp rate (I have this set low, but if i plug into my compressor when it's already got pressure then it can't re-start it)

As mentioned above there are other more ghetto ways to make it work but they will draw huge current and make low torque so don't seem suitable to your requirements, (caps added to run, or using a bigger dummy 3ph motor to create the extra phases)

I had a friend try a vsd on a hoist but said it would barely lift the car so then he fitted a replacement single phase motor, I never asked how well it works now, but know he uses it daily.
 

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