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View Full Version : 240v to 220v cheap solution? For china stuff



j3dprints
20th Dec 2017, 01:22 PM
The servos and China gear I'm looking at online looks like it's not rated to 240v AC Aus mains. Is there a cheap 240v to 220v transformer or electrical solution I can use?

Looking at some of these servos, I would be a bit worried about powering them straight off my powerpoint:
https://www.aliexpress.com/item/AC-Servo-Drive-Motor-750W-2-39NM-220V-3000R-Min-NEMA32-Material-Conveying-New-1/32721780790.html?spm=a2g0s.13010208.99999999.273.bNJKSF

Wallerawang
20th Dec 2017, 01:44 PM
I have 5 of these or similar to these servo motors - 3 in my mill and 2 in my lathe and they run fine on 240V. I don't think you will need a transformer. I use my machines most weekends sometimes for 8 hours with no issues. Our supply transformer is just outside my shed and it gives me 253 volts at my machine and they still run cool with no issues for over 3 years now.
Steve

BobL
20th Dec 2017, 02:25 PM
Interestingly the specs on one part of that page do say

AC Voltage:208-230 / 240 V !


I wouldn't worry about it.

j3dprints
20th Dec 2017, 03:14 PM
I have 5 of these or similar to these servo motors - 3 in my mill and 2 in my lathe and they run fine on 240V. I don't think you will need a transformer. I use my machines most weekends sometimes for 8 hours with no issues. Our supply transformer is just outside my shed and it gives me 253 volts at my machine and they still run cool with no issues for over 3 years now.
Steve
These chinese ones from aliexpress? A lot do look the same

And yep thanks BobL, I was just a little paranoid cause I read some posts before about suppliers who put on 240v with VFDs but they won't guarantee them with Australian conditions. My electrical knowledge esp. AC is limited.

KBs PensNmore
20th Dec 2017, 09:30 PM
If you're really concerned I have a 240 -220 volt transformer, you can have for the cost of postage, you'd be doing me a favor taking it.
Kryn

BaronJ
21st Dec 2017, 01:52 AM
If you're really concerned I have a 240 -220 volt transformer, you can have for the cost of postage, you'd be doing me a favor taking it.
Kryn


Hi Kryn,

I have an isolation transformer like that, 50 - 60 Hz, 220, 230, 240, 250, in and out ! 5Kw though, needs a sack barrow to shift it !!! :oo:

KBs PensNmore
21st Dec 2017, 06:00 PM
Hi Baron, the one I have is about 2 kg, came out of some apparatus that I pulled apart from the local vet. Might have been an Xray machine, rings a couple of bells in the brain box. No variables switches or anything, 240 in 220 outlet plug.
It's FREE, plus Postage if anyone wants/needs it.
Will do a pic of it when I go out to the shed shortly.
Kryn

NedsHead
21st Dec 2017, 08:19 PM
If you really do need 220v maybe a variac is another option

j3dprints
21st Dec 2017, 09:47 PM
If you're really concerned I have a 240 -220 volt transformer, you can have for the cost of postage, you'd be doing me a favor taking it.
Kryn
Thank you Kryn, I'd really appreciate that. I'm about to pull the trigger on buying the servos.

Servos are roughly 1200
Steppers with feedback are 1000 (but Leadshine, a bit less random of a brand).
Umming and ahhhrrring a little still.

BaronJ
21st Dec 2017, 09:59 PM
Hi Guys,

Kryn, the transformer I have has removable end plates and you have to move the input and / or output cable ends to a marked tapping. It could also be used at 110/110 V as well. These transformers used to cost a lot of money, its probably worth more in scrap copper today.

Re: Variac, I have one of those as well ! Another monster, 20 amp if I remember correctly, that weighs around 50 or 60 kilo. It used to have a motor attached to the shaft, but I re-purposed that years ago.

NedsHead
21st Dec 2017, 11:41 PM
My Variac is only a baby (10amp) and about 20 kilo, it occupies a milk crate on a low shelf in the garage.

It has a Bakelite wheel on top to adjust the voltage, I feel like Dr Frankenstein every time I use the thing!