Ryandevlin17

Hi,   I'm writing a short code to deduce the speed of a rotor using the time it takes between pulses of a rotation sensor, and use this value to determine if it is underspeed/ overspeed / correct - the program seems to be working fine but there are variables which I'd like to be able to edit. There might not be a HMI for all of the application we will use this program in so I was going to edit the float values directly from the modify menu on the LCD screen - the issue I'm having is that I can modify Bool values etc but when I try to modify a float I cant change the value as there is "Protected!" text - how can I remove this?   Picture attached.

Thanks very much both of you for your help I will try using the RTO as opposed to TON

Is there a way of getting elapsed time from timer in Allen Bradley - I am used to Tia portal and using the ET function of timer block, is there anything similar I can use here?   EDIT: I have written a short bit of logic here will this work or will the unlatch zero the ACC value before its written to F register?    

Hi,   I'm pretty new to allen Bradley and wanted to know if there was a function that could help me out. I have a rotation sensor which feeds back to the PLC via a digital input, once every half second or second once machine is up to speed - I want to record the off time of this DI (how long it is off between pulses, essentially how long it takes for drum to rotate once). Is there some way to record this time and use this value for compare logic? any help would be greatly appreciated.   PLC: Micrologix 1400 series B RSLogix 500 version 11.00.00 (CPR 9)