Do not alter the factory settings, because all the control parameters are dependent oncan we change the frequency controlling method of the inverter(s) in such a way that there's no problem in web tensioning process ?
Also the main motor is starting when the speedometer on the digital screen shows the speed of 5 m/min , although it was starting as the speed increased from 0 to 1 m/min , why is it so ?
You find the differencies by looking these pictures........
Control methods
–Open loop algorithms
–Closed loop algorithms
View attachment 64313
View attachment 64312
View attachment 64311
View attachment 64310
Here is all the text & pictures ..............
Very good seminar presentation papers
Implementing Embedded Speed Control for AC Induction Motors
http://am.renesas.com/media/products/mpumcu/child_folder/Renesas_Jani_Seminar.pdf
I could not find any documents or information about this machine
in order to be able to answer questions,
I need to know the machine structure and see the control block diagram
Do not alter the factory settings, because all the control parameters are dependent on
one another.
This is usually used tension control principle..............
View attachment 64598
Tension control in print units depends on manufacturer system design,
it can be done via tension measure before or after print units and
control decrease infeed speed or increase outfeed speed.
( Can´t say without machine tech. documents )
How the speed is measured, have you any instructions for calibration the speed measuring system.
( Wrong speed feedback can cause the problem. )
Motor VFD`s principle of operation is chosen by the manufacturer and matched to the other components of the control system.
If changing them , can lead to severe problems.
KAK
Direct torque control - Wikipedia, the free encyclopedia1) constant torque control : indirect ? (in v/f control)
2) What is dynamic torque control ?
DCCT = DC current transducer & ACCT = AC current transducer3) What is DCCT ?
control has no real current- / speed- feedback ,4) closed loop with estimation , what do you mean by estimation ?
One Shunt Current Detection or Single Shunt Current Detection (OSCD or SSCD)5) what is OSCD & OSCD Method ?
Generally we can say that , fans and centrifugal pumps are variable torque loads.6) difference between constant torque control & torque control ?
For example >> Look post #52 : Pictures 2, 3 & 4where are these used ?
I could not find any documents or information about this machine
in order to be able to answer questions,
I need to know the machine structure and see the control block diagram
Do not alter the factory settings, because all the control parameters are dependent on
one another.
This is usually used tension control principle..............
View attachment 64598
Tension control in print units depends on manufacturer system design,
it can be done via tension measure before or after print units and
control decrease infeed speed or increase outfeed speed.
( Can´t say without machine tech. documents )
How the speed is measured, have you any instructions for calibration the speed measuring system.
( Wrong speed feedback can cause the problem. )
Motor VFD`s principle of operation is chosen by the manufacturer and matched to the other components of the control system.
If changing them , can lead to severe problems.
KAK
Direct torque control - Wikipedia, the free encyclopedia
DCCT = DC current transducer & ACCT = AC current transducer
control has no real current- / speed- feedback ,
closed loop is estimated ie. calculated approximations is used instead of
feedback measurement values.
One Shunt Current Detection or Single Shunt Current Detection (OSCD or SSCD)
View attachment 64751
Generally we can say that , fans and centrifugal pumps are variable torque loads.
At 50% speed the torque is 50% so the power needed is only 25%.
For example , a conveyor takes the same torque whether it is running 0.1 m/s or 10 m/s,
so at 50% speed it needs full torque at 50% power.
------------------------------------------------------
Because I don´t have any tech. or service documents for this machine,
it is "mission impossible" to tell you what to do.
So I asked , do you have a instruction manual to calibrate the speed measuring system ?
and do you have any technical and maintenance manuals of the machine at all.
what is mean by " constant torque control indirectly " ?
&
What is mean by " dynamic torque control indirectly " ?
Schematics show only
S7-200 CPU 226
and analog input and output modules
Digital inputs from
-buttons 14pcs
-relays, contactors 3pcs
-limit switches 2pcs
Digital outputs to
-relays, contactors 14pcs
-lamps 2pcs
-alarm bell
-press roll 6pcs
-heat blow 6pcs
Four analog inputs
from potentiometer sensor for
-unwind
-infeed
-outfeed
-rewind
Six analog outputs for
-main motor
-infeed motor
-outfeed motor
-unwind A motor
-unwind B motor
-rewind A motor
-rewind B motor
Communication port1
as FvM wrote
Without PLC program list , we can´t say anything
about logic and functions between inputs and outputs.
In addition, we should know the machine mechanical design
and placement of sensors and motors locations in web-line.
(Exact how the controlled web goes through rolls,
locations of the rolls measured with potentiometers
locations of the rolls driven by controlled motors )
Please read through this document carefully
AC Induction Motor Fundamentals
Read this particularly careful.
CONTROL TECHNIQUES
Various speed control techniques implemented by
modern-age VFD are mainly classified in the following
three categories:
• Scalar Control (V/f Control)
• Vector Control (Indirect Torque Control)
• Direct Torque Control (DTC)
pages 19...21
https://ww1.microchip.com/downloads/en/appnotes/00887a.pdf
KAK
For which extended module are you referring to ?
kak111 isn't but retelling the signal names from your schematic. In addition you need to know, that EM232 is analog output and EM235 analog input module etc., just a quick look into the S7-200 catalog.
Have you not read your own attachments ,
all have been told there (post #68).
Additional info
Micro PLC SIMATIC S7-200 for less complex automation tasks - Programmable logic controllers from Siemens
kindly just name these ?
the last EM235 (E1) PLC module has the input of all the four potentiometric sensors and the output is going to the Rewind motor B ,
it means that whenever there's a problem in the alignment of the swing arm then there has to be the problem in the Rewinding B motor, Am i right ?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?