TROUBLESHOOTING
ERROR INDICATIONS AND CORRECTIVE ACTION
5 - 2
WBPEEUI240755B0
®
Control Module Errors
The multi-function processor (MFP) performs status checks on
the I/O module. An error will appear in the report function of
an operator interface. Refer to the appropriate instruction
manual for the operator interface you are using for an explana-
tion of these reports.
Function Code (FC) 79 output block N+9 in the MFP configura-
tion is the I/O module status flag (logic 0=good; logic 1=bad).
Use an operator interface to monitor this block. If the status
flag is a logic 1, check the front panel module status LED and
the operator interface report function to determine corrective
actions.
NOTE: If FC 79 specification S19 is set to 0, the MFP will trip when
the CIS or QRS module fails or the analog input reference voltages
are out of tolerance. Changing specification S19 to a 1 will allow the
MFP to continue to operate if any I/O module error condition exists.
Analog input
reference error
The MFP generates an ANALOG INPUT REFERENCE ERROR if
the I/O module reference voltages (1 VDC and 5 VDC) used to
calibrate the analog input zero offset and gain are not within
tolerance or the analog inputs are not within tolerance.
1. Check the analog inputs to verify that their voltages are
within specifications (1 to 5 VDC).
2. Check the analog inputs to verify that their common mode
voltage is within specifications (
±
10 VDC).
If the analog inputs are correct, replace the CIS or QRS mod-
ule.
Missing slave
module error
The address set on address switch (S1) and in the MFP config-
uration must be the same. The MFP generates a MISSING
SLAVE MODULE ERROR if they do not match. Verify that the
address set on switch S1 is the same as the address in FC 79
specification S1. If not:
1. Remove the module and change the setting of switch S1 to
correspond with the MFP configuration (refer to the
for the procedures to set an address and to install an I/O mod-
ule).
-
or -
Red
(FAIL)
(continued)
Bus fault timer error
(time-out)
Dipshunt not installed
between MFP and I/O
module
Verify dipshunt is installed in the I/O
expander bus socket on the MMU back-
plane between MFP and I/O module
Table 5-1. Status LED Indications and Correction Actions
(continued)
LED State
Indication
Probable Cause
Corrective Action
