irondesk40
Member
have something that i could use some advice on. Have a machine in one of our off shore plants that has a spray bar that is 10 inches long and pivots in the middle. The plc is a slc505 and the stepper card is a 1746 hstp1. The only thing i know at the moment is that the card is set up as well as the stepper drive that controls the turning of the spray bar so that 20000 pulse will rotate the spray one full revolution.
In the hmi a operator will enter that the fabric width is anywhere from 0-10 inches wide. The card is set up as a absolute type move and there is a home switch that is made when the bar is straight out across a piece of fabric that is 10 inches wide.
total length of bar is 10 inches center pivot point
To me it would appear that if a value for example of 0 inches was put in as the width then if you sent 5000 pulses then the bar would rotate 90 degrees and now be in the followin gposition
Since this would be the same as a fabric width of 0 inches, the bar would move to a position of 5000 since one full revolution is equal to a value of 20000. Could you not use the scp instruction and scale the operator input of 0-10 inches to a value from 0-5000? I was told by a coworker that it would not work that you would have to use trig math functions to figure out how far to rotate the spray bar.
Am i way off on my thinking on this, have to admit math is not my strong point, so any advice would be appreciated. I have not actually seen the machine yet, but will be going over in a couple of weeks.
Thanks
In the hmi a operator will enter that the fabric width is anywhere from 0-10 inches wide. The card is set up as a absolute type move and there is a home switch that is made when the bar is straight out across a piece of fabric that is 10 inches wide.
total length of bar is 10 inches center pivot point
To me it would appear that if a value for example of 0 inches was put in as the width then if you sent 5000 pulses then the bar would rotate 90 degrees and now be in the followin gposition
Since this would be the same as a fabric width of 0 inches, the bar would move to a position of 5000 since one full revolution is equal to a value of 20000. Could you not use the scp instruction and scale the operator input of 0-10 inches to a value from 0-5000? I was told by a coworker that it would not work that you would have to use trig math functions to figure out how far to rotate the spray bar.
Am i way off on my thinking on this, have to admit math is not my strong point, so any advice would be appreciated. I have not actually seen the machine yet, but will be going over in a couple of weeks.
Thanks