dclink, and universal converter to use

[crying_baby]

I cannot guide you without the documentation for the unit.
If you have the documentation for the unit, then you probably dont have to ask outside for help.

jesper, i got what u mean.

Thanks.

 

[crying_baby]

the manuals are realli brief on the external signal to control the igbts

http://www.leybold-didactic.de/ga/7/735/735296/
http://www.leybold-didactic.de/ga/7/735/735297/

only this 2 pieces and a motor

 

[JesperMP]

"735296" is jus a break-out box netween the VFD output stage and the control unit.
"735297" is the VFD output stage.

Obviously, each unit has its own manual.
Find the manual for the control unit.
Download, and print out ALL the manuals for the units that you have !

 

[JesperMP]

"735296" mentions external control units 735291 and 735292.

 

[crying_baby]

"735296" is jus a break-out box netween the VFD output stage and the control unit.
"735297" is the VFD output stage.

Obviously, each unit has its own manual.
Find the manual for the control unit.
Download, and print out ALL the manuals for the units that you have !

ok i go thru all the manuals in the available equipment in lab

but, in 296 its stated that , for external manual control og the igbts, it requires that the 2nd ribbon cable to be disconnected. that means, no use 735291.

735291 has a ribbon, to communicate to 735296's 2nd ribbon,

mean while, i m also readxing the others manual now

 

[JesperMP]

If you control the VFD "manually", i.e. with something else than the control unit, then you should not attach the control unit.
As you can NOT control the IGBTs directly from the PLC, your only chance is to locate and connect the control unit.

 

[crying_baby]

ok , jesper

 

[JesperMP]

This is my final post in this thread.

The control unit requires either a +/-10V signal for the setpoint, alternatively 8 digital signals. It appears that only one parameter can be controlled dynamically - the output frequency.
You should investigate if you have enough digital outputs in the PLC, or if you can attach an analog output module.

That said, what can you prove by providing the setpoint by the PLC, and not by just a potentiometer ?
(it is a rethorical question, please do not try to answer it).

Signing off, and good luck - Jesper.

 

[crying_baby]

The control unit requires either a +/-10V signal for the setpoint, alternatively 8 digital signals. It appears that only one parameter can be controlled dynamically - the output frequency.
You should investigate if you have enough digital outputs in the PLC, or if you can attach an analog output module.

That said, what can you prove by providing the setpoint by the PLC, and not by just a potentiometer ?
(it is a rethorical question, please do not try to answer it).

Signing off, and good luck - Jesper.

thanks jesper

 

[crying_baby]

by rhetorical question , do you mean cant be done using PLC? must use potentiometer?

 

[Lancie1]

Crying Baby,

Oh, boy, you have blown it now. You just lost your best hope of help in this area!

I find it amazing that you are working in a lab filled with potentially dangerous objects....

Please tell us some background information about yourself. Where are you from, what is your educaton level, what is your native language? This might help to lower ill feelings. :nodi:

By "rhetorical" Jesper meant that it was asked for "effect or style only", not a serious query.

I am beginning to wonder if this is an early April Fool's prank? It really emulates a good one. Someone would have to know a LOT to act so un-knowledgable...

 

[crying_baby]

Oh, boy, you have blown it now. You just lost your best hope of help in this area!

I find it amazing that you are working in a lab filled with potentially dangerous objects....

Please tell us some background information about yourself. Where are you from, what is your educaton level, what is your native language? This might help to lower ill feelings.

By "rhetorical" Jesper meant that it was asked for "effect or style only", not a serious query.

I am beginning to wonder if this is an early April Fool's prank? It really emulates a good one. Someone would have to know a LOT to act so un-knowledgable...

lancie, i already told the prof that the voltage is too high for me to implement this, he insisted>> if possible, he wants to c the motor's at least, 1 of the outcome from the proposal, the rest he opt for theory.

this is my project but, before this, i had only had a simple lab of ladder programing, nothing else, the professor said its possible to get a plc +inverter in market, that means , he sees possibility on working on this lab equipments,

how? insane huh?> this is my degree project, i have to admit, it is very risky, if i fry any part of htem, i havent bought
myself insurance yet!!

Please tell us some background information about yourself. Where are you from, what is your educaton level, what is your native language? This might help to lower ill feelings.

my only plc background was last year, 2nd half, i got a lab in control systems, only on programming PLC ladder, and c the output(lights) on a switch board, thats all. i dont know, that, the propose a such a technical PLC in mind... -.-"

I am beginning to wonder if this is an early April Fool's prank? It really emulates a good one. Someone would have to know a LOT to act so un-knowledgable...

NO!!! i m serious. at first i thought it was just a matter of doing the ladders, thta is why, i pick the proposal, well, it turns out NOT as straightforward.

its after a week, the professor, inform me that i m given the equipments, posted in teh picture to work on


-------i need help, i m trying to get a pass on this project,

 

[JesperMP]

I got PM'ed by CB for help, and I PM'ed him back.
Normally I dont think that one should post the PMs on the regular forum, but in this case I will make an exception (well I dont post HIS PM, it must be OK to post my own PM).
My reason for doing so is that I think that CB's best option right now, with the limited time available until summer (which is probably when he has to finish), is to start cracking with the books and the lab equipment, and stop asking others to do the works for him.

Crying Baby,

I feel sorry for you, but I am pussled to as to how you could get into this situation.
You mention "professor", "electrical engineer" and "degree work" in your previous posts.

If you are really in the final year of becoming an electrical engineer at a university or similar, then 3-phase AC motors should be second nature to you. You should know the principles of VFDs as well. You should have partaken in lab excercises with e-motors (and possibly the VFD+motor+load unit you are looking at).
It sounds like all this is new to you, and I find that a bit shocking to be honest.

And, I dont think hooking up a PLC to the control unit of the VFD makes for a real engineering degree. It is simply too trivial and basic. The "project" looks more like preparations for a lab excercise than a degree project. I find it odd that your professor think it is enough to get a degree.

I can only recommend the following.
Read up on AC motors.
Read up on VFDs.
Read all the manuals for the laboratory VFD, and set it up for testing it without a PLC. Make it run with an external +/-10V source for the setpoint.
If OK so far, connect your PLC with an analog output module to the VFD and make a test with that.
You will then have achieved your professors suggestion.

If CB has a question about a particular topic, then he can ask again, but he should not ask how to get the lab equipment up and running. We cannot do that from here. and he MUST be able to figure that out himself.

 

[crying_baby]

jesper, how did u know that it requires 8digital input from the +/- 10volt

it only menitions input voltage range is -10v ...+10v in 735291

 

[JesperMP]

CB,
you could use either +/- 10V, or 8 digital inputs, or serial comms (not sure about that last one, it is from memory and from a quick browse thru the manual).
I didnt check the details, but I guess that the 8 digital inputs must be configured by means of the keypad.