I need someone smart, clock project

[victorherr]

I need someone really smart to help me with a clock project,
I have a SLC 500 and a Panel view 550, I need to show on the panel view how many units are wasted per hour/day.
I know that im running 6 units per minute and I also know how many units get rejected.

any help would be good.

 

[leitmotif]

OK so you know good ones and bad ones. The question is how is the PLC going to know that and detect it? That seems to me to be the first hurdle.
More info is needed on process.

Dan Bentler

 

[LadderLogic]

I need someone really smart

Then you are in the wrong place.

 

[Brian_WI]

The plc already knows how many units are rejected, so just divide that by the total number of hours run gives you units/hr wasted....I would think, just a crazy guess=)

 

[Longhorn]

All you need to do is count the number of rejects over say 6 minutes then multiply the number of rejects by 10 to get rejects per hour and remember to zero the reject count and timer when the 6 minutes are up.

How to display this on the HMI i am unsure as im not familiar with panelview.

LH

 

[victorherr]

Sorry for not explaning this a little better, I would like to show on the panel view on a timed schedule how many units are rejected, I already know how many units are rejected I just don't know how to program the clock part of it, it has to show the units every hour and possible every 8 hours. I have a photo eye that counts how many units are bad, I just need to incorporate that amount to a clock.

 

[OkiePC]

Do you want the clock to be based on actual time or for each hour following an event (like a reset pushbutton, or operator log-in)?

You will probably want a counter for each hour. Reset them all at the beginning of the shift, and only increment the particular counter for the current hour when a new bad part is detected.

Paul

 

[victorherr]

Does this mean that i need 24 counters for each hour of the day?

 

[Controls_Engineer79]

however you wana do it in the plc your going to need to use a series of "move" commands to copy the Acc values of your timers and counters to N7 data files - - then in your panel view you'll wana ceate a numeric display which will be tagged to whatever N7 data file your moving your data into - thats how i would do it

do all of your math and scaleing in the PLC and just display the finished value in a numeric display on your HMI - maybe add a reset momentary PB on the HMI beside it so you can reset your totals. Do you wana maybe have two displays - one showing bad parts per 6 min and one showing a total for that shift?

tis up to you

 

[Controls_Engineer79]

24 counters per hour? naaaaa

you should only need maybe 2 counters? one to count the parts per 6 min period - one to keep track for the entire shift

use a free running timer set for 6 min, and have the first counter increment whenever theres a bad part - then when the timer reaches ther preset - as it resets - use the done bit to reset the counter as well - you can use some math functions to give you your 6 min average -average per shift - ect

i could help if you like?

 

[victorherr]

thanks, i kinda knew i needed to do all this on the actual PLC program, i
don't know how to trigger a value every hour for the panel view to see.

 

[victorherr]

when u said a free running timer you mean the PLC timer right?
i was working with S40 adress to get the hours, but still struggling a bit.
Thanks control Engineer.

 

[Controls_Engineer79]

just a standard PLC Timer T4:0/0 for example - - have a normally closed contact on the same rung as it sent to its DN bit - T4:0/0.DN so when the timer hits preset it opens for one scan - reseting the timer which begins to time again

standard free running timer circuit

 

[widelto]

Victor I did the same but with good part counter, yes you can use S40, but i would use S41 instead, so any time S41=0 means there is a new hour, move what is inside bad part counter (ACC) to a FIFO, use two fifo one for bad parts counter accumulator and the other one for S40 ( hour ), both fifo must have 24 places one for each hour, the idea is to have bad parts and hour saves in a place. so this can be displayed on a HMI. OLne data is save inside the fifo, you have to reset the counter and start from zero once again, so basically you will need only one counter.
If you want to display bad number in real time just have to display .acc of accumulator, I guess bad parts per hour are less than 32000.

 

[TConnolly]

With a little bit of indirect addressing using the S:40 register as a pointer and a 23 word file you can keep a rolling record of the last 24 hours very simply. From there it should be pretty simple to get the shift totals and daily totals.