3
TROUBLESHOOTING
This chapter describes errors that may occur while using the high-speed counter module, and those troubleshooting.
Throughout the chapter, the I/O numbers (X/Y) and buffer memory addresses are described on the basis of
the case of CH1.
To check them of CH2, refer to the following:
Page 54 List of I/O signals
Page 60 List of buffer memory addresses
3.1
Procedure for Troubleshooting
If a trouble occurs, try the following troubleshooting steps:
1.
Check whether each module is mounted and wired correctly.
( MELSEC iQ-R Module Configuration Manual)
2.
Check the LEDs of the power supply module and CPU module. ( User's Manual of each module)
3.
Check the error cause and corrective action by the symptom to correct the error. ( Page 48 Troubleshooting by
Symptom)
3.2
Checking Module Status
An overflow error can be checked in CH1 Overflow detection (Un\G8).
Error information to be detected by the high-speed counter module
Description and cause
Overflow error
• In linear counter, an up pulse has been counted
from the present value 2147483647.
• In linear counter, a down pulse has been counted
from the present value -2147483648.
Where to check the error information
Overflow detection flag
CH1 Overflow detection (Un\G8) stores one of the following
values:
• 0: No overflow
• 1: Overflow occurred
Action
Execute a preset to clear the overflow
error.
3 TROUBLESHOOTING
3.1 Procedure for Troubleshooting
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