The batch record says the mixer started at 06:14 and the operator watched it start at 07:14, on the Sunday the clocks moved. The CPU 1516-3 PN/DP is keeping perfect time. What is wrong is that somebody wired RD_SYS_T into the timestamp and RD_SYS_T hands back the module time, which on this family is always … Read more
MOVE_BLK with COUNT := 20 aimed at an ARRAY[1..10] of Real on a CPU 1516-3 PN/DP does not put the CPU in STOP and does not hand you an error in the diagnostics buffer. The enable output drops to 0, and on a box inserted with the editor’s default settings there is no ENO pin … Read more
The display reads TORQUE TRIP CLOSED, the IQ40 on the raw water isolation valve has stopped short of its closed limit, and the operator has pressed close four more times with nothing happening. That second part is not a fault: PUB002-040 says that once the actuator meets its set torque between the limits it stops … Read more
The servo-on command is made, the drive display sits at b01 or its axis number, RD never comes on and the machine will not start its home position return. No alarm, no warning, nothing flashing. A Mitsubishi servo home position that refuses to set is almost never the servo’s fault, and on an MR-J4-A configured … Read more
Write a torque reference into DINT 1 of a PowerFlex 755’s output image and the drive will run at that many hertz. DINT 1 is the Reference, it is a 32-bit REAL, and 750COM-UM001 says plainly what it scales to: drive speed, in whatever P300 [Speed Units] is set to. There is no torque word … Read more
Fault 64 on a PowerFlex 755 reads Drive OverLoad on the HIM, and the first move most people make is to open the motor overload group and start editing P413 [Mtr OL Factor]. That is the wrong fault. A PowerFlex 755 fault 64 is P940 [Drive OL Count] arriving at 100 %, and P940 counts … Read more
The bagger came back with 0.0 in every recipe setpoint at 06:10, with nobody at the HMI and no download on the log. The only change on that shift was a program that had been inhibited while somebody edited it and then put back in, and the initialisation rung inside it — one XIC on … Read more
A 20-750-S seated in port 4 of a PowerFlex 755, SP and SE landed on separate contacts of a 440R-D22R2, twenty-four volts measured on both pairs, and the drive faults the moment the contactor closes. The SAFETY enable jumper is still on the main control board, where it ships from the factory, and the manual … Read more
Four guard doors on a packing cell, a Trojan T15 tongue switch on each, 440K-T11390, all four pairs of contacts daisy-chained into one 440R-D22R2 relay, and the calculation for that stop function will not go past PL c. Every switch in the chain has its two direct-opening N.C. contacts, the wiring matches the drawing, and … Read more
Reading a CompactLogix Fault: The Four Places the Controller Says What Broke I/O Fault Local:2 #0203 Connection Timeout scrolls across the front of a CompactLogix 5380 for a few seconds and then the display moves on to the project name and the IP address. That one string is four separate pieces of information, and on … Read more
When the 1734-IB8S Will Not Run: Reading the Diagnostics First MS flashing green on a 1734-IB8S means the device is in the Idle or Standby state, and the recommended action printed next to it is to configure the module and establish a connection. Nothing about the module is broken. It has powered up, passed its … Read more
Scaling a 4-20 mA Temperature Transmitter on a CompactLogix 5380 Put Low Signal 4 mA, High Signal 20 mA, Low Engineering 0.0 and High Engineering 250.0 into a 5069-IF8 channel and Local:2:I.Ch00.Data arrives at the controller as a REAL already in degrees Celsius. There is no scaling rung, no raw count, and nothing for a … Read more