Motor stuck in 1 direction

cliff t

Member
Join Date
May 2019
Location
Nevada
Posts
16
Good Day Group,


I am having an issue between my logic and the VFD that is controlling my motor. The VFD is an Automation Direct GS1. In my logic O2 is run/stop and O1 is direction (closed = CW and open = CCW, rung 6, line 3). What I am trying to accomplish is "if counter is equal to 1 then energize coil" (top rung line 15)and when the coil goes high the corresponding N.O. contact on rung 6, line 3 will close and energize coil O1 to change direction. For some reason I cannot get O1 to change states and am not sure if it might be my logic or an issue with the VFD. It seems pretty straight forward to me but obviously I am missing something and am hoping another set of eyes night be able to see something I am missing. For reference rung 4 (the top rung) is timing and rung 6 is motion. Thank you all in advance and have a great day!


Regards,
Cliff

logic.JPG
 
Cliff, when you say you can't get O1 to change state, are you sure it's not? You go on to say that you don't know if it's your logic or the drive....but you need to figure that out first. Is O1 for sure not changing state? What do you seen when the logic runs?
 
It appears to be the logic, O1 is high no matter what. I am going to remove O1 from the logic and if still high check wiring to ensure that somehow we are not getting juice regardless of logic state.
 
Apparently my eyes are not as good as I thought, based on the indicator lights on the IO module (I got 2 second opinions for confirmation) O1 is NOT going high. For some reason I am not getting O1 to change states based on the counter.
 
Are the counters accumulating as they should? I ask because I'm accustomed to seeing a line of logic leading to a counter's reset node and not simply a Boolean variable name.
Also, since you have the output of the "Equal" function controlling the counters, could it be possible that the value in R30 is accumulating by more than 1 per scan such that the value is never exactly equal to R150 or R120? How about the state of the S10 bit? If S10 is always off you never see a change of state at the counter inputs and the counters can't increment.
 
I know that the counter on line 13 is operating as it should because I am seeing an increase in "current cycles" (line 15 on rung 4 - R330)when the motor makes 2 start/stop cycles so I figured I could just piggyback another counter onto it to energize O1. The S10 on line 18 is the "start" button that starts and stops the program, that bit is "held in" by a setting on the HMI panel and turns on/off by being pushed or turned off by the program. The reasoning behind that NC is "if the program is started (F1 pushed and held in) then the contact opens and the timer reset is controlled by the equal comparator on line 13 and when the program is stopped then the cycle timer will be reset by the NC. I am going to try and remove the counter, coil and contact and just have O1 connected directly to see is I can see a signal at all.
 

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