# Vfd



## Jmohl (Apr 26, 2011)

Ok, first of all, most VFD do not come pre-programmed. That said, they are not too difficult to do. You need to know nameplate data on the motor such as HP, voltage, etc... also, your input power whether its single ph. or three phase, voltage, hz,,,, Now on to the rest of the parameters. Is the motor going to run at one pre-set speed or follow a 4-20ma or 0-10vdc. How are you starting and stopping it? Do you need it to come up to speed almost instantly like a cross the line starter or soft start? Do you want the load to coast to a stop or be braked? Just stuff you need to know for the application.... Second, almost any three phase motor can be controlled with VFD. If you are going to have the motor run extremely slow under high torque though, an inverter duty motor would be advisable as the fan won't cool a gen. duty motor enough under such conditions. As far as OC protection, yeah the VFD will give you over current trip but I generally like at least a set of fuses under them for short circuit protection..... VFD aren't magic, but they can do a lot of cool things... Also, if they are using VFD for pre-set speed control within about 5hz from nameplate, they are wasting money. A different gear ratio, sprocket speed or even a variable sheave would be cheaper and just as reliable...


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## John Valdes (May 17, 2007)

ask_eddie said:


> I am suppose to provide power to an Allen Bradley Powerflex 70 feeding a 15hp
> They are suppose to provide the AB and the motor, Ive never worked with a VFD so please excuse these basic questions. From searching the internet, it seems the OL protection is provided by the VFD itself.?
> Since these are being provided to the company as a package deal are these programed ? do they normally need set up programing ?I will not be providing any of this Im just wondering.
> Can any basic AC motor be used with a VFD or are they a special type of motor.
> ...


First thing you need to do is calm down and take it easy. This will be a fun experience for you and its not difficult to set up and operate.
Second. Contact the vendor that is providing this package and ask for start up help. You can learn a whole bunch if you have someone there with you on the first one. Take advantage of the salesman that is involved with this project. He is invested in this as well as you are. In this day and age these guys are technicians in addition to being sales reps.

Now to your questions.
Yes, the OLR is not required as the VFD provides its own OL protection. It is possible some basic programming may be included depending on the deal your company made with the vendor. In most cases you must program the control yourself. 

Why are you not "_I will not be providing any of this Im just wondering_". What does this mean? Is the vendor going to perform the start up? If so just get in there with them and learn how to program a control. Ask many questions.

Yes, any three phase motor will operate on a VFD. However, older motors may not be able to withstand the output from the VFD and fail.
The do build and sell VFD specific motors. In many cases this is not required. Many manufacturers now market all their three phase motors as "inverter duty" or "inverter ready".

It sounds like all you are doing is supplying three phase power to their control cabinet or VFD.
They can tell you what type of OCPD you need and the wire size. In fact most VFD manuals have this information included.

Are you installing a line reactor. This goes on the input side, so you need to find out before you pull any wire or set the disconnect. The line reactor must be as close to the drive as possible.
If they have not encouraged the purchase of the line reactor, it may be included as part of the VFD. Ask them.


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## travelingelec (May 31, 2011)

What they said. programing them is easier then you might think. The schematics should have the settings to program it. If not, wright them down.


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## Wirenuting (Sep 12, 2010)

Installing them is easy. I'm doing an ABB these next few days up on a mezzanine. 

John is right about the salesmen having a vested interest in it being done right. Give them a call. Ask about a warranty start up and a rep coming out for it. 
The biggest headache for me is when I'm replacing older / larger cans for these newer compact models. 
The piping is never the same for entry.


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## RIVETER (Sep 26, 2009)

I have put in about 15 or twenty this past couple of months. All required a dynamic brake. That may be because of the loading of the roll beds with trucks on them.


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## sagnew (Mar 24, 2011)

Hey Eddie, 

Your an electrician, you have every right to be wiring this thing up! You just need a little educating:thumbsup:. Power goes to L1, L2 & L3. Motor connects to T1, T2 & T3. If the motor goes backwards swap two of the motor cables(T1,T2,T3) not the line cables(L1,L2,L3). If all the control wiring is done for you already than your job is done:thumbup:. 

If you have to program the drive or do the control wiring, write another post with the info and we will help you out!


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## MDShunk (Jan 7, 2007)

It's completely normal for a packaged, pre-engineered system to already have the drive programmed. John's acting like the world's coming to an end or something. 

Get power to the drive, then from the drive to the motor. Pretty simple. Your job is done. If it's someone else's equipment, you don't even have to press the 'go' button... just be on standby to check rotation when they do.


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## nitro71 (Sep 17, 2009)

MDShunk said:


> It's completely normal for a packaged, pre-engineered system to already have the drive programmed. John's acting like the world's coming to an end or something.
> 
> Get power to the drive, then from the drive to the motor. Pretty simple. Your job is done. If it's someone else's equipment, you don't even have to press the 'go' button... just be on standby to check rotation when they do.


Finally someone gets it :thumbsup: I'm always working with guys that want to get their beaters in places they don't belong or they have no monetary responsibility to be in. 

If you didn't engineer the project. You didn't source the VFD's. And your contract doesn't specify you setting them up. It's someone elses ball of wax after you make terminations.


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## Wirenuting (Sep 12, 2010)

Most drives I have installed came with adjustable O/L's. 

Except todays. 

It came with out the heaters and there was no control transformer. 
The o/l's I pulled from the old unit after the helper tossed it into a dumpster on the way to another job. 
The tranny is a question mark. Boss was to let me know hours ago if I was to use the old one. Or if it was a mistake by the supply house. 
It's a Danfos unit labeled as a trane. 

O'well, to late, I'm done and heading out.


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## JRaef (Mar 23, 2009)

Wirenuting said:


> Most drives I have installed came with adjustable O/L's.
> 
> Except todays.
> 
> ...


If it doesn't have Bypass Contactors, you may not need the OL relay or a CPT. 

But if it has an OL relay and they didn't supply heater elements, that's usually something that the person who orders it is supposed to take care of, because the mfr will have no idea what the motor FLA is. The same can sort of be said for CPTs, they have no idea what the line voltage is (although they are usually dual voltage anyway). A lot of times packaged drives like this are supposed to be coordinated by the packager, in this case Trane. Sounds like they did a piss poor job of it.

A lot of these mechanical equipment suppliers don't know squat about ordering electrical gear, yet they insist on providing it because they want the money for it. Grrr....


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## Wirenuting (Sep 12, 2010)

JRaef said:


> If it doesn't have Bypass Contactors, you may not need the OL relay or a CPT.
> 
> But if it has an OL relay and they didn't supply heater elements, that's usually something that the person who orders it is supposed to take care of, because the mfr will have no idea what the motor FLA is. The same can sort of be said for CPTs, they have no idea what the line voltage is (although they are usually dual voltage anyway). A lot of times packaged drives like this are supposed to be coordinated by the packager, in this case Trane. Sounds like they did a piss poor job of it.
> 
> A lot of these mechanical equipment suppliers don't know squat about ordering electrical gear, yet they insist on providing it because they want the money for it. Grrr....


We always get the bypass option. To many times we have been dead in the water for 6+ months. It takes a long time to fund repairs sometimes. 

This one has the o/l block and was empty when I opened it. Piss poor planning does not create an emergency on my part.


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## I_get_shocked (Apr 6, 2009)

We installed two Eaton Cutler Hammer VFDs this weekend. They were actually pretty fun. We did both controls and line voltage.

Power to L1, L2, L3
Load to T1, T2, T3
Grab Nameplate info, enter it in the VFD LCD screen.
Check rotation in bypass and in hand.
Land Control wire Start/Stop, Speed, Fault, Frequency, etc


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## MDShunk (Jan 7, 2007)

I_get_shocked said:


> We installed two Eaton Cutler Hammer VFDs this weekend. They were actually pretty fun. We did both controls and line voltage.
> 
> Power to L1, L2, L3
> Load to T1, T2, T3
> ...


Since people are getting increasingly serious about LOTO, please add the 4th contact to any local discos to disable the drive, lest you blow it it up.


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