Is this motor compatible with using a vfd

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tangogeko

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Hi all the is my first post so not sure if this is the right forum . But I have this felder table saw which is 3 phase I would like to run it off 1 phase I was thinking to use a vfd.
Done a bit of research but still not 100% sure open to other options as well. Here is a photo of the motor plate

any help would be much apricated,

motor specs on saw are as follows

V 400
Kw 3
A 5
Hz 50

it is a 2005 felder winner so there's no warranty on it
 
If you go the jfk route above, they are a clever device and a good choice, but you must buy one big enough. It isn't a 3kW drive for a 3kW motor. You need to size up, substantially.
Best way is to contact the seller, explain your application and ask them to recommend the right drive.
Also, download the manual and read it carefully beforehand so you understand what you are buying and how to install it.

Good hunting.
 
It isn't a 3kW drive for a 3kW motor. You need to size up, substantially.
Yes an important point because you have the one input producing three outputs. So you need the square root of three or 1.73 times which is around a 5kW convertor but most will just double the motor rating to have plenty of spare capacity and give the convertor less stress. But you might want to buy an even larger one so as you have the capacity to run what you have not yet purchased because you can get a lot of machine cheaper if it is three phase.
 
Yes an important point because you have the one input producing three outputs. So you need the square root of three or 1.73 times which is around a 5kW convertor but most will just double the motor rating to have plenty of spare capacity and give the convertor less stress. But you might want to buy an even larger one so as you have the capacity to run what you have not yet purchased because you can get a lot of machine cheaper if it is three phase.
motor plate needs to read 240V - 380V
Motor plate reads 220/440
 
If that is the case you could use an invertor but my preference has always been the convertor simply because it can run much larger loads and you do not need to alter anything on the machine. Also never buy a cheap invertor, there are many around but buy branded.
 
but I’ll only really be running this one machine off 3 phase
You say that now but maybe next week a nice three phase spindle moulder comes up at a good price or something else that you cannot turn down, it happens and these older machines are in a different league to what we get now.

A decent invertor is not cheap, plus 3kW is the limit wheras with convertors it is your electrical supply.
 
You say that now but maybe next week a nice three phase spindle moulder comes up at a good price or something else that you cannot turn down, it happens and these older machines are in a different league to what we get now.

A decent invertor is not cheap, plus 3kW is the limit wheras with convertors it is your electrical supply.
Is the inverter/converter choice influenced by the high probability that only one machine will be powered up at any one time?
Brian
 
Is the inverter/converter choice influenced by the high probability that only one machine will be powered up at any one time?
An invertor is wired to a single machine, it cannot be used to supply sockets because it cannot be powered up without a load connected, ie cannot have the outputs open circuit which often applies to many hifi power amps. The convertor on the other hand can be used to power up sockets and therefore you might have several machines connected because the convertor can be run without a load. A convertor can also power machines greater than 3kW unlike the invertor so opens up the market to bigger machines but this is all dependant on your electrical supply. The best option is a true three phase supply, next would be a three phase generator then a convertor and as a last resort an invertor. Invertors work much better when handling three phase in and three phase out and are used in many renewable energy systems.
 
A digital phase converter is a great convenience in allowing you to just plug in and run any old 415v / 3ph machine. And indeed more than one at a time.
You will be paying a good few hundred £ for it but it is a one off. Think of it like buyi g a transwave converter, just better in every respect.

If you go VFD, then you need to buy a drive and amend the wiring for every individual motor.
That might cost as much in the long term. I think I've got about 6, including a couple of 2.2kW and a couple of 4kW, whose total cost would definitely be more than a 5 and maybe even 7kW digital phase converter.

VFD is better in that I have the option of variable speed and custom tuning on every motor which a DPC can't do unless you "waste" it by dedicating it to one motor only. But DPC is easier long term.

Just watch out. 415V is much more dangerous than 240V so do your wiring rigorously - no amateur bodging - or get a professional in.

And the specific difference. VFD turns 240v domestic mains into 240V 3 phase so it only works with "dual voltage" motors that can be wired to run at 240V.
Digital phase converter has an additional stage in the electronics so it increases the 240V mains upto 415V 3 phase so you don't need a dual voltage motor.
 
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If that is the case you could use an invertor but my preference has always been the convertor simply because it can run much larger loads and you do not need to alter anything on the machine. Also never buy a cheap invertor, there are many around but buy branded.
Ok I’ll just take the one off hit of the price
A digital phase converter is a great convenience in allowing you to just plug in and run any old 415v / 3ph machine. And indeed more than one at a time.
You will be paying a good few hundred £ for it but it is a one off. Think of it like buyi g a transwave converter, just better in every respect.

If you go VFD, then you need to buy a drive and amend the wiring for every individual motor.
That might cost as much in the long term. I think I've got about 6, including a couple of 2.2kW and a couple of 4kW, whose total cost would definitely be more than a 5 and maybe even 7kW digital phase converter.

VFD is better in that I have the option of variable speed and custom tuning on every motor which a DPC can't do unless you "waste" it by dedicating it to one motor only. But DPC is easier long term.

Just watch out. 415V is much more dangerous than 240V so do your wiring rigorously - no amateur bodging - or get a professional in.

And the specific difference. VFD turns 240v domestic mains into 240V 3 phase so it only works with "dual voltage" motors that can be wired to run at 240V.
Digital phase converter has an additional stage in the electronics so it increases the 240V mains upto 415V 3 phase so you don't need a dual voltage motor.
how are the converters wired in just from the mains supply then put 3 phase sockets to it
 
how are the converters wired in just from the mains supply then put 3 phase to it ?

Basically yes.
You will need a MCB circuit breaker dedicated to this in the consumer unit, so unless you have a spare one of the right size, that is an electricians job as it is notifiable work.

Correctly sized breaker and supply cable to the Phase Converter, then connect a number of 3 ph 415v sockets back to the converter. Just follow the manual. It's chinglish but pretty good and contains many pages of detail, unlike the cheap chinese VFDs.
 
I used to have a winner it has some intemediate electronics. It needs some big oompf on startup the single plase version needed a 20 amp slow trip fuse ( i think that is right terminology) so i can imagine it needing a poweful convertor. Great saw i swapped mine after 12 years for a smaller felder and i sold the hammer for the same money as the felder. Not a massive upgrade but i liked the felder green and the smaller table was better for me.
 
Just use the right equipment for the job, buy a convertor and not an invertor and your machine will run without any modifications. Also it can run multiple machines unlike the VFD which has to be dedicated to a single machine.

https://www.jfkelectricalni.com/product/digital-phase-converter-4kw-5-5hp-240v-in-400v-out/
The link says it will works as VSD as well so that that mean that it can control the RPM on say a 3ph spindle moulder or a lathe.
Thanks as always
 
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