CTI 2550-A, Installation And Operation Manual

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20 C T I 2550-A Installation and O peration G uide
Figure 19 Example I/O Configuration Chart
NOTE:
In the event a CTI analog detects an onboard module failure, the module will assert the module
fail line and report the module failure in the I/O Status Word, which is reported to the PLC CPU.
CTI strongly recommends the user application monitor the
I/O Module Status Words which are
Status Words 11-26 and apply to SIMATIC® Controllers 545, 555, 560 & 565 and the 575. The
I/O Module Status Word can be used to report a module failure for an I/O Module in any of the
505 I/O slots. Please refer to Siemens® SIMATIC® 505 Programming Reference Manual for more
information. If a module failure is reported by the status word, the module should be replaced with
a working unit and the failed module sent infor repair.
2.7 Checking Module Operation
First turn on the base power. If the module diagnostics detect no problems, the status indicator on the
front of the module will light. If the status indicator does not light, begins blinking, (or goes out during
operation), the module has detected a failure. For information on viewing failed module status, refer to
your SIMATIC® TISOFT user manual. To diagnose and correct a module failure, refer to the next
section on troubleshooting.
You must also check that the module is configured in the memory of the PLC. This is important
because the module will appear to be functioning regardless of whether it is communicating with the
PLC. To view the PLC memory configuration chart listing all slots on the base and the inputs or
outputs associated with each slot, refer to your SIMATIC® TISOFT Programming Manual. An
example chart is shown in the following figure.
In this example, the Model 2550-A module is inserted in slot 1 in I/O base 0. Data for channel 1
appears in word location WX1, data for channel 2 appears in word location WX2, etc. For your
particular module, look in the chart for the number corresponding to the slot occuppied by the module.
If word memory locations appear on this line, then the module is registered in the PLC memory and the
module is ready for operation.
If the line is blank or erroneous, re-check the module to ensure that it is firmly seated in the slots.
Generate the PLC memory configuration chart again. If the line is still incorrect, contact your local
distributor or CTI at 1-800-537-8398 for further assistance.