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View Full Version : more VFD help - Me Electrically STUPID



KiddZimaHater
02-16-2010, 06:55 PM
Ok guys, Please help. (again)
I have my new toys. (VFD, 3-phase motor) And I'm ready to wire them up.
I'm also electrically ignorant. I couldn't tell a volt from a jiggawatt, and I really-really-really don't want to fry/screw-up my new goodies.
So here are my questions:
1) Can I use the 220 outlet that I plug my welder into for my VFD? Instead of having a dedicated on/off switch? Can I just unplug it when not in use?
2)About connecting my 220 to the VFD- There are 3 connections (U1-L,V1-N,W1), W1 is without a screw. So I connect my two wires into the two available screws (U1 and V1 obviously). But, do I need to wire them Live and Neutral, or can I just connect them either way? (See Photo with U1/L, V1/N)
http://img6.imageshack.us/img6/7995/vfdz.jpg
3) Motor wiring- Here's the wiring diagram below: This means I should twist wires 4,5,&6 together, and leave them isolated. Twist wires 9 & 3 together and connect to one incoming line. Twist wires 8 & 2 together and connect to one incoming line. And twist wires 1 & 7 together and connect to the third incoming line. Correct?
http://img10.imageshack.us/img10/330/motordia.jpg
Thanks for being patient and helping me. This is my first VFD.:)

gvasale
02-16-2010, 08:04 PM
When I got my first and only vfd (AC Technology) I wired it with a twistlock plug on the input. This one is for 220 vac, and unplug it when not in use. Don't use it on the mill, as I put a single phase motor on it. If you got directions, follow them. You must use the vfd for on/off, and there will be no instant reverse. Ramp up, ramp down. Depending on the size of your machine and the startup mass, leaving it on full (60, so to speak) may not be the best thing to do. Hope this helps.

Dawai
02-16-2010, 08:27 PM
Model and brand inverter?? series number?
Got a link to the pdf or manual?
Okay.. is it a 120 input inverter, or 220?

Not enough information to help from here.

psomero
02-16-2010, 09:13 PM
Ok guys, Please help. (again)
I have my new toys. (VFD, 3-phase motor) And I'm ready to wire them up.
I'm also electrically ignorant. I couldn't tell a volt from a jiggawatt, and I really-really-really don't want to fry/screw-up my new goodies.
So here are my questions:
1) Can I use the 220 outlet that I plug my welder into for my VFD? Instead of having a dedicated on/off switch? Can I just unplug it when not in use?




if you put a disconnect in there to kill the VFD with before plugging/unplugging it, absolutely. that's exactly how my mill and welder are set up.

KiddZimaHater
02-16-2010, 09:57 PM
Brand: ABB AC Drives
Model: ACS150
220 volt
.5 - 5.0 Hp
Link to User's Manual:http://www05.abb.com/global/scot/scot201.nsf/veritydisplay/4347a4759b348013c12576a500313486/$File/EN_ACS150%20UM_rev%20B.pdf

lazlo
02-16-2010, 11:11 PM
The 2 hots on the 240V line go to U1 and V1.

U-V-W go to T3, T2, T1 on the motor as you've got it wired in your diagram (T3/T9-T2/T8-T1/T7). Tie T4,5,6 together.
If the motor rotates the wrong way, switch any 2 of the outputs.

KiddZimaHater
02-16-2010, 11:43 PM
Thank You Lazlo. You've cleared it up for me.

Stuart Br
02-17-2010, 02:44 PM
Due to the large capacitors on the VFD, they can hold a high level of potentially lethal charge, which can be exposed to the pins of any plug on the input. This can remain for many minutes after shutdown. For this reason most VFD installation manuals will advise that they should be hardwired for safety.

Stuart

japcas
02-17-2010, 03:03 PM
The 2 hots on the 240V line go to U1 and V1.

U-V-W go to T3, T2, T1 on the motor as you've got it wired in your diagram (T3/T9-T2/T8-T1/T7). Tie T4,5,6 together.
If the motor rotates the wrong way, switch any 2 of the outputs.

You can also change the settings in the parameters versus manually switching two wires. I know you probably know this Lazlo but I wasn't sure if
KiddZimaHater did. After you get used to moving around through the menu screens making small adjustments to the running parameters will be a piece of cake and you'll wonder how you ever got along with out it.

J Tiers
02-17-2010, 10:39 PM
Due to the large capacitors on the VFD, they can hold a high level of potentially lethal charge, which can be exposed to the pins of any plug on the input. This can remain for many minutes after shutdown. For this reason most VFD installation manuals will advise that they should be hardwired for safety.

Stuart

generally, (but not always) if the display shuts off, the voltage is low enough to be not an electrocution problem. This is not a guarantee, but is a reasonable 'checkpoint" on residual voltage.

We have a 60kW specialty inverter system in final test now, which operates on a 750VDC bus (the inverter is standard, the control system is special). The inverter power supply operates from 850VDC down to about 60V on the bus, and when it shuts down, the DC drops rapidly.

If you see lights, it should be assumed to be live. 10 min after the lights go out, it *should* be discharged. It's worth checking,of course.

But in the absence of a faulted IGBT or diode, no output or input *should* have any hazardous voltage on it after the lights go out.

RobbieKnobbie
02-18-2010, 12:57 PM
If you want to be all official-like, you should have a disconnect for anything over 1.5HP. Below that you can call the plug a disconnect so long as its accessable.

As mentioned, you don't want to shut off the spindle and then sprint over to unplug the thing... let the caps dischange before unplugging or disconnecting. Personally I think a lot is made of that point - who actually turns off the spindle motor and immediately shuts down or unplugs the machin anyway? By the time you take the part out of the vise/chuck and measure whatever cut you just made, etc etc etc, the caps are bled down and you're good to go.

EVguru
02-18-2010, 01:39 PM
Due to the large capacitors on the VFD, they can hold a high level of potentially lethal charge, which can be exposed to the pins of any plug on the input. This can remain for many minutes after shutdown. For this reason most VFD installation manuals will advise that they should be hardwired for safety.

Stuart

There's usually an input rectifier, so how is the bus voltage going to appear on the AC terminals?

I've had minor shocks because I've been unlucky enough to unplug on the peak of the AV waveform and the EMC filter caps have been carring a charge. Not electrically dangerous, but the surprise could cause you to injure yourself against something.

Stuart Br
02-18-2010, 02:32 PM
From the Control Techniques Commander manual, for the unit I have hooked up to my Chipmaster.

"Equipment supplied by plug and socket
Special attention must be given if the drive is installed in equipment which is connected to the AC supply by a plug and socket. The AC supply terminals of the drive are connected to the internal capacitors through rectifier diodes which are not intended to give safety isolation. If the plug terminals can be touched when the plug is disconnected from the socket, a means of automatically isolating the plug from the drive must be used (e.g. a latching relay)."

So I guess that is saying that the rectifier diodes may give isolation, but they are not designed as a safety device.

lazlo
02-18-2010, 03:23 PM
There's usually an input rectifier, so how is the bus voltage going to appear on the AC terminals?

There are large electrolytic filtering caps between the rectifier and the DC bus. After you unplug the VFD, the display will usually stay lit for at least 30 seconds.

On several of my VFD's, there's a safety LED that indicates when the charge on the DC bus has dissipated.