New housing builds are being wired up with distribution cables that are about 3x the cross sectional area of the legacy stuff according to a recent chat with an engineer from my DNO. I wonder if 3x will be enough ?
Phase convertor
- Thread starter Hpps
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Hpps
Established Member
So after watching the video posted by Housey210 I think VFD is possibly the way forward. I'm not interested in getting a 3ph suply put in, I just want to run two machines I currently own, any future purchases will be 240v single phase, simple as that.
I'm not interested in future proofing incase I get an electric car, and I live in a listed house which is in a conservation area within a national park, who have said we are not permitted to instal ground source, air sourse, solar or wind power - they don't even want us to have outside lighting (but thats another topic altogether).
So keeping it simple is where I'm at.
If I were to buy VFD's for these machines, I assume due to the different hp ratings on the two motors I'd need two VFD's. So that being said, can someone point me in the right direction for which ones to look at as I expect they'd be different?
Secondly, would this then require the motors to be adjusted or altered to make them work with the VFD's?
I'm not interested in future proofing incase I get an electric car, and I live in a listed house which is in a conservation area within a national park, who have said we are not permitted to instal ground source, air sourse, solar or wind power - they don't even want us to have outside lighting (but thats another topic altogether).
So keeping it simple is where I'm at.
If I were to buy VFD's for these machines, I assume due to the different hp ratings on the two motors I'd need two VFD's. So that being said, can someone point me in the right direction for which ones to look at as I expect they'd be different?
Secondly, would this then require the motors to be adjusted or altered to make them work with the VFD's?
Ttrees
Iroko loco!
You could start by stating what single phase supply you've got.
Do you have 16a outlets, some would suggest that being required for the tablesaw,
as it's a three horse motor.
Is it just the 13a household you've got, that has you lookin up VFD's?
If so, then it's slightly frowned upon, regarding some mentioning the supply for the VFD needing double the FLA (fully loaded amp) rating of the motor.
It seems from what I can understand, that would be bad for the VFD's internal bits,
(how bout the motor folks?, school me more please on this)
I've not messed about with motors which were only 380/400v, just strictly dual voltage as of yet..
but from what I've seen online, I'd reckon there might be a chance, that its worth taking the time to pop off the lid on the terminal box, to see if you had options.
i.e six connections like what you'd have seen on Bob Minchin's Induction_ motors_Issue3.pdf
Not sure if I said that loud enough, perhaps outlining it might do the trick.
That will explain the basics, as in for motors which are "dual voltage", that's...
240v low voltage option, which usually has the triangle Delta/Triangle symbol,
but this isn't the case for your tablesaw motor, and looks strange to a Joe Soap like me.
That's along with the higher 380v Star/Wye option,
the configuration of the three brass straps like on my Startrite motor denotes this.
I'd speculate since you've suggested doing this on a shoestring, that a recommended VFD to
provide 400v might be viewed as a bit spendy.
Perhaps not so much with the lathes 1 horsepower motor?...
Not looked up the cost of 400v inverters, though there are some on the Ozzy forum using the cheap ones without issues.
That's, should it be the case it ain't actually"dual voltage" after all.
The lathe motor nameplate might just turn out to have information regarding the 380/400v
but perhaps some schematics for 240v voltage configuration under the lid.
Should the lathe motor not be dual voltage....
There are likely options to dig the windings out from the lathe motor, but it looks a delicate dicey procedure to find the three ends of the windings, dig them out and bring em out to the terminal box to convert the motor into dual voltage.
Guessing the lathe might be the first to get setup, should you not have the option of using it,
and you wish to swap out motors on the TS.
Sorry can't suggest much beyond that.
Good luck
Tom
Do you have 16a outlets, some would suggest that being required for the tablesaw,
as it's a three horse motor.
Is it just the 13a household you've got, that has you lookin up VFD's?
If so, then it's slightly frowned upon, regarding some mentioning the supply for the VFD needing double the FLA (fully loaded amp) rating of the motor.
It seems from what I can understand, that would be bad for the VFD's internal bits,
(how bout the motor folks?, school me more please on this)
I've not messed about with motors which were only 380/400v, just strictly dual voltage as of yet..
but from what I've seen online, I'd reckon there might be a chance, that its worth taking the time to pop off the lid on the terminal box, to see if you had options.
i.e six connections like what you'd have seen on Bob Minchin's Induction_ motors_Issue3.pdf
Not sure if I said that loud enough, perhaps outlining it might do the trick.
That will explain the basics, as in for motors which are "dual voltage", that's...
240v low voltage option, which usually has the triangle Delta/Triangle symbol,
but this isn't the case for your tablesaw motor, and looks strange to a Joe Soap like me.
That's along with the higher 380v Star/Wye option,
the configuration of the three brass straps like on my Startrite motor denotes this.
I'd speculate since you've suggested doing this on a shoestring, that a recommended VFD to
provide 400v might be viewed as a bit spendy.
Perhaps not so much with the lathes 1 horsepower motor?...
Not looked up the cost of 400v inverters, though there are some on the Ozzy forum using the cheap ones without issues.
That's, should it be the case it ain't actually"dual voltage" after all.
The lathe motor nameplate might just turn out to have information regarding the 380/400v
but perhaps some schematics for 240v voltage configuration under the lid.
Should the lathe motor not be dual voltage....
There are likely options to dig the windings out from the lathe motor, but it looks a delicate dicey procedure to find the three ends of the windings, dig them out and bring em out to the terminal box to convert the motor into dual voltage.
Guessing the lathe might be the first to get setup, should you not have the option of using it,
and you wish to swap out motors on the TS.
Sorry can't suggest much beyond that.
Good luck
Tom
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But as you know that is just a small part of the issue, I was informed that they will not only require larger csa cables but will also have more cables because each run from the sub can only supply so many houses if they are connected across all three phases. This now raises further issues because with existing supplies the infrastructure, ie ducts etc will also need to be larger and somewhere I read an article explaining that in many heavily populated areas the local subs would need to be put onto 33Kv rather than the existing 11Kv which then need larger footprints so as deema has said
is all to true, some little oock in some government department had some weird dream without any concept of reality or electrical understanding, probably the type who would happily plug extension leads into extension leads and then wonder why they are smoking, but not wacky baky.
guineafowl21
Established Member
Both the saw and lathe will need a step-up, or two-stage, VFD as they both require 400V 3ph as they are.
- Table saw will need a 3kW two-stage one (quite a beast). Since it doesn’t particularly need 3ph, I would swap for a single phase motor. Try TEC motors for advice - they’re very helpful.
- Lathe needs a 500W VFD, no harm in increasing to 750W (1 hp). A lathe definitely benefits from 3ph (smoother, and easy speed control).
Option 1: Two stage 1hp VFD. Try Drives Direct. Quite expensive. There are cheaper ones available, but I think these are normal ones that have been ‘hacked’ to put out the higher voltage.
https://www.ebay.co.uk/itm/154157585407?epid=21006216835&hash=item23e48213ff:g:qU0AAOSwPfhbhVQd
Option 2: Get the motor star point extracted at a motor shop, and use a cheaper, standard VFD. Newton Tesla do good all-in kits.
Option 3: New 3ph motor and VFD kit, either Newton Tesla or TEC will set you up. The lathe will be a different machine with controllable 3ph.
Option 4: Swap in single phase motor + control gear. Cheap and simple.
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