On an S7-1500 a 4 to 20 mA channel reads 0 counts at 4 mA and 27648 counts at 20 mA, and a channel with wire-break diagnostics enabled reads 32767 when the loop opens. Those three numbers decide the rest of this page: what goes in the MIN and MAX pins of NORM_X, what SCALE_X … Read more
An S7-1500 area length error leaves the CPU in RUN with the ERROR LED on. Read the buffer entry, find the index that runs past the array, fix the order.
A 1024 PPR encoder on the tail roller of an 8 m belt, read in X4 by a 5069-HSC2xOB4, gives 652 counts for every 50 mm of belt, and a shift register that moves one cell every 652 counts knows where a carton is to within one cell whether the belt is running at 0.500 … Read more
Maximum PROFIBUS segment length at every DP baud rate on type A cable, with repeater rules, termination values and the meter checks that find the fault.
Bit 0 of the PowerFlex 525 logic command word is Normal Stop, and it has to be sitting at 0 before bit 1 will ever start the drive. That footnote under the table in Appendix D of 520COM-UM001 is behind most of the drives that show a green connection in the I/O tree and still … Read more
How functional safety works on a PLC job: the ISO 13849-1 risk graph, PLr, category 3 architecture, MTTFd, DC, CCF, a PFHd budget and SISTEMA.
PLC programming for beginners without the theory dump: pick a simulator, write a start/stop rung, add a timer and a counter, wire one HMI button.
Several drives faulting F004 in the same second is a supply problem. How to work out the bus volts, log the sag safely, and read the trace it gives you.
P033 [Motor OL Current] on a PowerFlex 525 holds exactly one number. Land two 3 HP motors on T1, T2 and T3 and that number is now watching the pair as though they were one 6 HP machine, which leaves neither motor protected. That single parameter is the whole argument. Two standard induction motors will … Read more
F013 is current leaving the motor circuit for earth. A megger routine that separates motor, cable and junction box, with the readings that decide it.
Add one Static to an FB and every setpoint in the instance DB goes to zero. How the memory reserve prevents it, how to size it, and how to recover.
The CPU says V4.6 and the hardware catalog stops at V4.5. What a hardware support package does, how to install one offline, and when you need a newer TIA.