Help

[Nick85]

hey guys im learning plcs and need help with this exercise if anyone knows how to do this pls let me know.

1/10thsec clock pulse - design a routine to do this. so the speed change for a motor moves from fine-medium to course control with the of use Timers after three 3sec the medium control after 15 sec course control.

If anyone could help that would be great we are supposed to use INC and DEC functions.


regards

nick

 

[Nick85]

1. FINE CONTROL - Inc and Dec the speed value on every press of the button



2. MEDIUM CONTROL – Automatically after 3seconds Inc and Dec the speed value every 1/10th second



3. COARSE COUNTROL – Automatically after 15seconds Inc and Dec the speed value as fast as possible.

 

[tragically1969]

You need to specify which PLC type you are using, the commands are different between Mitsubishi, Omron, Siemens, AB, Modicon etc etc etc

THEN

Show what ladder have you written so far, nobody will write the code for you !!

 

[OZEE]

What do you have so far?? (I.e., we won't do your homework for you -- we'll help.)

Define exactly how it's going to work (e.g., flowchart). Define the elements of the system. Define how to manipulate the elements of your system. Define which controller you're using (the exact answer you're seeking cannot be given without knowing the platform you're using -- so far, we don't even know that...)

 

[Nick85]

this is sort of what ive done so far using syswin


0.00 0.01
-------l l-----l/l------(@INC)

0.01 0.00
-------l l-----l/l------(@DEC)


0.00
-----l l------------(TIM 16)
l0.01l 3sec
l_l l_l

0.00 TIM16
-----l l------l/l---(INC)

0.01 TIM16
------l l-----l/l----(DEC)

here I put in another timer so that after 15sec it woud go to an ADD function but i think it would make it to unstable.

0.00
-----l l------------(TIM 17)
l0.01l 15sec
l_l l_l

TIM17
----l l-------(ADD)
(DM100)
(#500)
(DM100)

 

[Nick85]

sorry all the addresses have moved hope u can still understand

 

[Nick85]

Here is some more details

-Syswin software, Omrom PLC

- Motor speed controled by PLC, Motor is wired to a Servo

- Control the speed up and down by push buttons wired to inputs 0.00 speed up 0.01 speed down.

-the Servo is wired to an analogue output card that gets it s reference from by reading DM100

- the value 0000 in DM100 would cause the motor to stop
the value 9999 would cause the motor to stop

- with this the program has to be written to vary the speed up and down with fine- course to rapidly inc or dec speed.

what I don t understand is how to run it a rapid speed
I know that if i use @INC 0r @DEC this will give you fine control because it is only read once, you would have take you finger off and press again to increase the value by one more.
I know when I use the function without (@) that when your finger is held down the value will increase by 100 because PLC scan runs at 10ms so after 1 sec of the button been pressed the value would be 100.

now I don t know how to make it ay faster this is where i am stuck

pls help

 

[Nick85]

sorry the value 9999 would cause the motor to run at top speed

 

[Nick85]

hi i have written some more details hopefully you can understand what im on about

thanks