VFD question

[NevNZ]

I'm looking for some advice for my Optimum TM3110 lathe, purchased new last week from Scott's Machinery New Zealand. It's not making anywhere near full RPM.

It seems that the lathes are modified in China with a VFD added so the 3 phase motor can be run on single phase. The lathe achieves close to the stated RPM in most gears (+/- 50 RPM) except the top gear where it should 2000 RPM, but only gets about 160RPM. It's not a mechanical gear ratio issue as such. It appears to be that the motor is stalling, like a car trying to go uphill in gear that's too high.

I don't have a lot of knowledge in this area. Scotts have tested the other lathes in stock and found the same issue. A label on the lathe states 400v, 1.1kw 2000RPM, but another label states 230v, so I presume they've been modified to better suit the home hobby market and our normal power supply which is 230v.

So I'm wondering whether the cause is likely to be the VFD and its settings, or the motor ? Is it likely to be fixed by changing the settings ?

Any advice appreciated.

 

[tq60]

Since you contacted the vendor and they confirmed same issue in theirs, do nothing. Period!

The vendor can work with the supplier to get the issue corrected.

Assuming it is simple programming, the vendor can work on the stock machines until he confirms the fix, then he coukd supply simple instructions for you to follow.

Or, on a bad side, it coukd be not correct something, wrong motor or VFD.

You already contacted the vendor, if by email be sure it has your serial number and everything else.

Do a follow up email to confirm your reported issue, and ask them to confirm in the email what the lathe was sold to do.

Remind the vendor that you will wait for them to solve the issue, but will expect it to be corrected under warranty.

Ask them to confirm that you can use the late as is without risk to yourself or warranty.

If using the lathe risks warranty, then that changes things.

Also of note, in most states, the warranty clock stops when a warranty covered item is reported during warranty period.



Sent from my SM-G781V using Tapatalk

 

[markba633csi]

I assume you meant to type 1600 not 160?
The VFD settings may not be optimized for the motor power demand at the highest speed- some improvement may be possible
it may take some experimenting
Be sure to record the original settings if you decide to adjust any

 

[NevNZ]

I assume you meant to type 1600 not 160?
The VFD settings may not be optimized for the motor power demand at the highest speed- some improvement may be possible
it may take some experimenting
Be sure to record the original settings if you decide to adjust any

Um.....no, I wish it was . It makes quite a loud "electrical" whining, and very reluctantly turns over slowly. I guess that being the highest gear ratio there's just not enough umphh in the motor to turn that gearing. The next lowest gear speed is 1000 RPM, which it does achieve, but it takes about 30 seconds to wind up to speed. The other gearings are all fine and get up and going quickly.

 

[markba633csi]

Oh then there is definitely something wrong with the programming I think
Some of the ramp up and current limiting settings need to be checked- the VFD is throttling back and it shouldn't be
Do you have a link to the VFD manual for that unit?

 

[mksj]

Motor appears to be 400V version, as it is indicating 2.8A, a 230VAC 1.1kW (1.5Hp) motor would run 2X that so around 4.8-5.2A. The VFD is rated for single or 3 phase input with an output rating of 7.5A so is correct. Wrong motor voltage, and does not appear to be a dual voltage motor that could be rewired for 230VAC 3 phase input.

 

[NevNZ]

Oh then there is definitely something wrong with the programming I think
Some of the ramp up and current limiting settings need to be checked- the VFD is throttling back and it shouldn't be
Do you have a link to the VFD manual for that unit?

Here's a link to the manual.

Thanks.

 

[markba633csi]

Is the motor truly a 400 volt rated unit? What does the motor nameplate give for voltage?
I'm going to check the manual but I am skeptical that the VFD is expected to step up the incoming from 230v to 400v three phase
They must have changed out the motor or something is really mismatched like Mark said in post#6

 

[NevNZ]

Wrong motor voltage, and does not appear to be a dual voltage motor that could be rewired for 230VAC 3 phase input.

So (to check my understanding) would this mean that the motor is not correct for the purpose? In other words that it's not a more simple case of adjusting the settings to better suit.

Much appreciated.

 

[NevNZ]

Is the motor truly a 400 volt rated unit? What does the motor nameplate give for voltage?
I'm going to check the manual but I am skeptical that the VFD is expected to step up the incoming from 230v to 400v three phase
They must have changed out the motor or something is really mismatched like Mark said in post#6

Let me check and get back to you. The far end of the name plate is a bit more difficult to access.