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Slasher102
26-01-2023, 10:30 PM
Hi all i have a quick one that i just need clearing up by someone with more vfd and motor knowledge than me.
i was told that to use a vfd on a 3 phase motor it had to be 220v/380v compatible not just 380v

can anyone shed any light on this for me please.

i know about star and delta, it was more about the label on the motor without the 220v/380v

Cheers

m_c
26-01-2023, 11:55 PM
It depends on what output voltage the VFD is.

Generally VFDs output a 3 phase version of whatever voltage you feed in, so if you want to run one from typical 240V single phase, you'd need a motor that can be wired to accept 240V 3 phase. Which for a typical* induction motor, means wiring it as delta, as opposed to star which you would do typical UK 380/415V 3 phase. These motors will usually have a plate that gives dual voltage/current ratings for 230 and 380V.


However, you can get 'boost' VFDs, that will take 240V single phase, and output 380V 3 phase.



I say typical, as I have come across induction motors (generally older ones), that are internally connected as delta but are rated for 380/415V.

Slasher102
27-01-2023, 09:20 PM
Many thanks the motor i have is just 380/415v so i would need the boosted vfd i think.

Thanks again

m_c
27-01-2023, 10:57 PM
It all depends on if the motor can be changed between delta and star.

Some motors are only labelled for a single voltage, but are changeable. It depends on the manufacturer, and how the purchaser spec'ed the motors.

Slasher102
27-01-2023, 11:10 PM
Many thanks the motor i have is just 380/415v so i would need the boosted vfd i think.

Thanks again

Slasher102
27-01-2023, 11:32 PM
i have a picture of the plate, what would you recommend



31682, ?

Slasher102
27-01-2023, 11:36 PM
i see you have replied to members about the conect 121 don't suppose you have any details on the controller board pinouts.

m_c
28-01-2023, 12:27 AM
i have a picture of the plate, what would you recommend



31682, ?

That's a two speed motor which complicates things, but also means it's likely to only run on 380V.
Dual voltage/dual speed motors are theoretically possible, but it involves switching 12 coils.

Easiest option is a boost VFD. Have a search for them on Aliexpress.
I personally use CNCWeiken ones - https://cnweiken.aliexpress.com/store/group/220V-to-380V-VFD/5248031_516106264.html but there is another brand others on here have used however I can't remember the name.

You'll want to eliminate any switching in the wiring between the VFD and motor.

m_c
28-01-2023, 12:29 AM
i see you have replied to members about the conect 121 don't suppose you have any details on the controller board pinouts.

No, but from what I remember the main board had a processor built in, so there wasn't really much in the way of pinouts. Just motor/spindle controller connections, along with the serial connector.
There was an upgrade option for some of thier machines, but a full retrofit would be a better option now.