Basic advice to control a Delta VFD-B for automated run-in cycle

[tfry200]

Hello everyone,

First off, my disclaimer- I'm a mechanical guy. A bit of a computer geek on the side, but nothing crazy. What I'm being asked to do is to set up an automated run-in program for electric motors. We control these motors with four Delta VFD-B drives. What I want to do is step up these motors through an 8 hour overnight run in. Since this will be unattended, I need to have it shut down if the motors reach a certain temperature.

I know that the VFD itself is able to step the speeds up, and has parameters for a shutdown, etc. but I'm not sure if that is the best way to go about this. I was thinking that a PC might be the easiest solution? I'm hoping this would also give me the ability to record information about the run-in: temperature, current, voltage, etc.

I've googled around but I'm not familiar enough to know which is the most logical way to go about it. Can anyone give me any advice on a direction I should be headed?
i.e. should I be looking for some PC card to control this, or is the RS-485 serial connector on the VFD going to be enough to get me going?

Or...am I getting in over my head here?

Thanks in advance for any advice anyone can lend.

Tim

 

[jraef]

I don't know a lot about the Delta drives, but assuming it is a relatively modern version, it should have RS485 serial comms available and most likely uses Modbus protocol. But that is only 1/2 the battle because unless you are an experienced programmer, this is likely to all be Greek to you. You need some sort of operating program to do the control, then you need a database program to record the data. That part could be done with something as simplistic as Excel, but again, you would really need to be good.

Do you have a budget to make this happen?


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> faq731-376

 

[tfry200]

jraef,

You are correct on both points--the Delta VFD does have a RS485, and it can use MODBUS ASCII or MODBUS RTU, according to the manual.

I've got a budget of 'minimal' Just kidding (well, kind of. ) I can probably spend a few thousand to do this.

For the temperature recording I've been looking at this:

http://www.alliedelec.com/search/productdetail.aspx?SKU=3891458

But you're right--that's only half of my battle. I need to program it. I see Delta has some software called VFDSoft that I'm HOPING might help? I'm just wanting to make sure i'm on the right track and there's not something easier out there that I'm missing.

With the RS485 connections--I have 4 VFD's, so are there something out there that I can use to easily hook 4 of these up to a computer?

Tim

 

[itsmoked]

You can get RS485 drivers that will provide that for a PC all over the place.

You should certainly run this all with a PC. Since it is unattended you want to log everything so when something goes south you know what. Nothing is worse than knowing something went wrong but not having a clue what, then having to try to repeat it.

If you haven't done this kind of stuff before you should just buy a package to do it.

Whatever you do don't buy a single piece of hardware until you positively understand how the software is going to work. It's no fun not buying hardware, but I have seen the stressful nightmare caused by the wrong order of purchasing stuff. (I may have even been in that situation myself a few times - no no I would never be such an idiot.

)

Check into LabView.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[fangas]

Since you haven't done this before, I'd like to ask a few questions.

1). What is the purpose of this run-in ? Do you want to see if these motors will function for 8 hrs without self-destruction? Or ?

2). Will the run-in involve loaded or unloaded motors?

3). What temperature are you concerned with? Motor temps very all over, depending on where you measure.

I ask, because you say you have a limited budget and based on experience in years of testing motors and setting up motor test systems. You can either seriously overkill and overspend, or underkill.

Ed

 

[tfry200]

fangas,

My company repairs these motors and it is our procedure to go through a run-in process to break in the bearings and ensure that everything is functioning as intended. They run without a load. We measure the temperatures at each bearing, and at the winding. I need to make a record of the temperatures during the run-in and provide for a shut down if they start getting out of hand. The procedure and temperatures we look for are already established.

Thanks for the assistance here.

 

[sreid]

If you can settle for shutdown on over temperature, a low end PLC like the Mitsubishi Alpha 2 might be the easy way to go.

http://www.meau.com/eprise/main/sit...ontrollers/Alpha2_Sequence_Controller/default

 

[fangas]

I agree with SReid on temperature shutdown. Especially if you're sorta new to this stuff, and have a limited budget. Measuring current & voltage out of a drive can't be done using conventional methods. You'll need some true RMS measuring. And that can get expensive.

The easiest way would be to pick those up from the drive and and feed them to the software as part of the trending function. I looked at the manual for the software and it does have that function. However, there is no mention of being able to do it simultaneously on multiple drives.

You might start with a call to Delta and explain to them what you are trying to do. They might be able to help.

how are you measuring temperatures now?

Ed

 

[tfry200]

I follow you that I can control the VFD and get the electrical information using the Delta software. I will talk to delta about it but I was hoping that I could either control 4 units or at least run 4 instances of the program to control each.

So are you guys recommending I set it up so the system shuts down at a certain temperature, but not try to incorporate tmperature recording into it? I think that is possible within the VFD also, but I was really hoping to get some data recorded.

We are doing the whole process manually at the moment--stepping up the VDF's, recording current and voltage, and the temperature readings are taken hourly with an infrared gun. Not exactly high tech or time-efficient, but that's what I'm trying to help.