637
Troubleshooting
Section 12-2
12-2 Troubleshooting
Use the following procedure to check error details and remove the cause of
the error if the CPU Unit does not operate when the power supply is ON, oper-
ation suddenly stops and the error indicator (ERR/ALM indicator) lights, or if
the error indicator (ERR/ALM indicator) flashes during operating.
12-2-1 Error Processing Flowchart
Confirm the error category by referring to the status of the CPU Unit indica-
tors, investigate the cause for the error in the error tables, and take corrective
actions.
12-2-2 No Operation When Power Is Supplied
First confirm that the POWER indicator (green) is lit.
POWER Indicator Not Lit
The power supply may not match the Unit rating, wiring may not be correct, or
the Unit may be faulty.
1,2,3...
1.
Confirm the Unit rating (i.e., is it 24 VDC?) and see if the supply power
matches the rating.
2.
Check the wiring to see if it is correct and that nothing is disconnected.
3.
Check the voltage at the power supply terminals. If the voltage is normal
and the POWER indicator is not lit, the Unit may be faulty. In that case, re-
place the Unit.
POWER Indicator Turns OFF and ON
There may be fluctuations in the power supply voltage, disconnected wiring,
or poor contacts. Check the power supply system and wiring.
POWER Indicator Lit but No Operation
Check the RUN indicator if the POWER indicator is lit but the CPU Unit does
not operate. The CPU Unit may be on standby if the RUN indicator is not lit.
Error occurred.
POWER indicator lit?
RUN indicator lit?
ERR/ALM indicator lit?
There is no error in the
CP1L-EL/EM.
Check for other causes
(section 12-3).
Check the power supply
(sections 12-2-2 and 12-3).
ERR/ALM indicator lit?
A non-fatal error has occurred.
Refer to section 12-2-5.
A fatal error has occurred.
Refer to section 12-2-3.
Lit
Not lit
Not lit
Flashing
Not lit
Lit
Not lit
Lit
Summary of Contents for CP1L-EL20DR-D
Page 3: ...CP1L EL20D CP1L EM30D CP1L EM40D CP1L EL EM CPU Unit Operation Manual Produced July 2017...
Page 4: ...iv...
Page 10: ...x...
Page 22: ...xxii...
Page 34: ...xxxiv Software Licenses and Copyrights 7...
Page 192: ...158 Trial Operation and Debugging Section 5 3...
Page 250: ...216 Automatic Clock Adjustment and Specifying Servers by Host Name Section 6 7...
Page 666: ...632 Trouble Shooting Section 11 7...
Page 696: ...662 Standard Models Appendix A...
Page 805: ...771 Connections to Serial Communications Option Boards Appendix F Connecting to Unit...
Page 806: ...772 Connections to Serial Communications Option Boards Appendix F...
Page 836: ...802 PLC Setup Appendix G...
Page 838: ...804 TCP Status Transitions Appendix H...
Page 840: ...806 Ethernet Network Parameters Appendix I...
Page 842: ...808 Buffer Configuration CP1L EL EM Appendix J...
Page 844: ...810 Ethernet Specifications Appendix K...
Page 851: ...Index 817 work words 118 write protection 447...
Page 852: ...818 Index...
Page 854: ...820 Revision History...
Page 855: ......