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2/21/2019 1:36 PM | |
Joined: 9/30/2016 Last visit: 8/15/2024 Posts: 914 Rating: (6) |
Please also see the attached screenshots. I have a problem with some sensors (Schmersal RSS 36-D-ST / RST 36-1). Such a sensor is placed each end of a bumperbar and both sensors must be "happy" (in the correct position) in order to operate the machine. This position is registered on to FDI's (and there are 2 bumperbars on each machine so 4 FDI's are needed but the bumperbars are not"mixed up in each other") Each sensor has 2 normally open switches and they are "cross wired" on the machine so that both sensor must be OK for even one FDI to be OK. Unfortunately the sensors will not give 2 OK FDI's even though they ARE in the correct position. I have tried to crosswire the sensors as they are on the machine to 2 "normal" DI's on a test PLC and use a timer to register the time difference on the to channels. It is between 40 and 140 ms (probably due to scan times etc.). When I look at the discrepancy times of the FDI channels used they seem to be 10 or 20 ms. Would it help to increase these to 250 ms? And would this be OK? How do I interpret the numbers shown on the FDI parameters? How does channel 4 relate to channel 16? Why do some have 10 ms and some have 20 ms (100% difference)? Why is channel 7,19 to 11,23 set to 1-channel (evaluation)- is that as safe as 2-channel? AttachmentDiscrepancy time 1.zip (206 Downloads) |
Last edited by: xmnj at: 2/22/2019 7:01:29 AMSpelling |
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