Rockwell Automation 1771-PD PID MODULE (+DU) - Manual (Page 135)

Troubleshooting
Chapter 4
4Ć3
Table 4.B
Program Troubelshooting Guide
Indication Probable Cause Corrective Action
Incorrect analog input, tieback input, PV input Programming plugs for conditioning the inputs
are selected incorrectly.
BCD or binary format is chosen incorrectly
Transmitter is misĆcalibrated.
ReĆcheck programming plug selection.
See section titled Internal Selections.
ReĆcheck W01 B12, B11 for BCD or binary
format.
ReĆcheck range and span of transmitter.
Incorrect analog output As above
Actuator is miscalibrated.
As above
ReĆcheck actuator.
Loss of PV input bit is set PV from analog input is not being received.
PV from PC processor is not being received.
(The loss of PV input is reported if no signal is
present).
Check signal wiring, module and transmitter
power supplies and input conditioning.
Jumper PV (+LEAD) to +15V DC power
connection. (Loss of pV is reported whether
or not the PC processor is downloading the
analog input).
Block transfer does not occur Ladder diagram program contains an error. Check that the block transfer instruction
module address matches the PID module's
location in the I/O rack.
Check preĆconditioning of block transfer
rungs.
Verify that the program is similar to the
example program in the appendix.
Check bits B17 and B16 in the first word of
each write block transfer to ensure proper
settings for dynamic, loop 1, and loop 2
blocks. Check block start address words for
correspondence to data table file locations.