View Full Version : VFDs?

02-06-2010, 08:30 PM
I bought a secondhand Omron 3G3MV AB040.

I have to test the VFD as soon as it arrives, after some time waiting for the bloke to answer my email he asked me to send him an email saying I wouldn't ask for my money
back if it didn't work; which I obviously refused to do. So I need to test it
works as soon as I get it.

I haven't ever run a VFD before.
Can I just wire it up and switch it on?
Should I leave the motor wires off and switch it on and peruse the menus and set stuff prior to connecting the motor and switching on?
The motor it will be running is a Yaskawa spindle motor (http://www.yaskawa.com/site/dmspindle.nsf/link2/TKUR-5EKT25/$file/SIE-S626-1.2D.pdf)
Or are they well protected and fault or complain in some way if the settings are wrong?

02-06-2010, 10:42 PM
Most modern VFDs are pretty well protected, but NEVER run one without the motor connected. In general the factory defaul settings will usually work OK, but you would then tune them to work with the motor (things like ramp up, min and max speeds, etc.) Wiring up is easy, but you'll need some suitably rated 4-core cable, preferably screened and ideally a line filter.

When you switch it on the motor wont run until you press the run button... you can usually program it all then before starting the motor....

I assume you have the setup guide (http://www.datasheetarchive.com/pdf/Datasheet-078/DSAE0060346.pdf) for the Omron 3G3MV-AB040? This is single phase to 3-phase at 4Kw (approx 5HP), and I assume you have the smallest spindle motor which is listed at 3.75kW.

03-06-2010, 01:16 AM
I assume you have the setup guide (http://www.datasheetarchive.com/pdf/Datasheet-078/DSAE0060346.pdf) for the Omron 3G3MV-AB040? This is single phase to 3-phase at 4Kw (approx 5HP), and I assume you have the smallest spindle motor which is listed at 3.75kW.

I have the same pdf, well it's got 21 pages more and is twice the size, strange!
Yes i have the small spindle motor, I was looking for a 7.5 hp inverter but the people at inverter.co.uk
reconed a 4kw would do, if i wasn't going to cane the spindle. The motors are listed 3.7 continuous and 5.5 for 30 mins.
So i just plug it in and press buttons.

I have several filters from the original setup, how do they work? they would be for three phase.

03-06-2010, 09:03 AM
The filter you need is a single phase one (http://cgi.ebay.co.uk/Rasmi-Single-Phase-RFI-Filter-3G3JVPFI-1020-E-NEW-/150382093362), at the input to the VFD as shown in 2.2.5 of the manual (although that shows a 3-phase filter but the idea is the same). Ideally the output wire should be wrapped through a ferrite ring (http://cgi.ebay.co.uk/13mm-Ferrite-CLAMP-Choke-Filter-Reduce-RFI-EMI-TVI-/390193924941)(of the right size for the cable) to kill high frequency harmonics. It will work quite happily wthout either but you may get noise back into the ring main (not that you are going to run this off the ring main with an input current of 16A, needs a direct connect back to the board on a 20A MCB)

That PDF is issue 2, maybe yours is a different issue - use the later of the two.

06-06-2010, 06:07 AM
Well all didn't go well.
I connected it to the motor it will be running. Set the parameters listed in the 'simpletons guide to getting
started' bit of the pdf. That's just re-setting the V/f parameters to default[which would be a 5kw motor]
and setting a maximum current.
Hit run and the spindle accelerated very slowly to maybe 25 or 30 rpm before an oL2 error appeared. oL2 is
inverter overload. played with the V/f settings, upping the voltage as 12V at 1.5 hz didn't seem a lot.
It accelerated a bit better on the next go, but still really slugish and oL2 error again.
So I whacked it on my coolant pump, I set the max current a lot lower but left every thing else as it was.
The pump doesn't have a plate, probably got washed off, but the motor is a good 6" diam by 6inch long.
It accelerated nice and smooth took it up to 200Hz still pretty good.

So not very promising.

06-06-2010, 03:45 PM
and this inverter is definitely a 5kW jobbie, has the right markings etc? The other question is how is the motor wired, star or delta? There is very little data on the 'approved' controller for that motor on the Yaskawa web site so its hard to tell if there something unusual going on. Clearly the inverter is working tho...

06-06-2010, 11:30 PM
It's a 4KW inverter. I mailed inverter.co.uk last year about one and they thought a 4kw would be OK with the motor as long as I
wasn't pushing it to hard.
The motor has three wires, very thin wires, coming out of it. But it's a jap motor and the nameplate states:

07-06-2010, 12:25 AM
Are you using the inverter in vector or v/f mode (see section 5.1.2 of manual). I think it needs to be in v/f mode (n002 = 0, which is the default), however because this motor is not designed to run below 1500rpm some of the other defaults are inappropriate. You'll need to set values n011=205, n012=173, n014=53 , n016=53, n017= 127

07-06-2010, 01:31 AM
I am running it in V/F mode. I set all the parameters available in V/F mode. I set the ones you mentioned as you suggested.
and N036[max current] as default which is 19, I also tried 16 and 25 no difference.
The motor is run so it gives spindle speeds from 40 to 4000, then for the optional 60 to 6000 they supply a bigger motor pulley
and for xxx to 10,000 they come and re-set a parameter and charger you $1200 so I am told;-) So the motor should be ok down
to 2hz.
I tried upping the low voltage, ie the 2hz voltage from 12V to 24V and it improved, but still overloaded at a similar point.
They show a graph where they suggest to set n011-n017, not sure if it's just for clarity but they show it with a lot of slope.
If you graphed my figures there wouldn't be a lot of slope?
Email Yaskawa time?

30-06-2010, 05:42 AM
Well spoke to a bloke at a place that advertises as a yaskawa motor and drive supplier, reconed
the drive and motor were developed for matsuura and they had mended original drives as they couldn't get
them working with new drives!
Had an email today from yaskawa, I had outlined the problem and asked about solutions, bloke suggested
either installing the original drive, or fitting a generic 3phase motor and vfd.
So looks like I am going to be fitting another motor.