Hardware Fault Detection During Connection Buildup - Siemens SIMATIC S5 Manual

Installation Guidelines
3.5

Hardware Fault Detection During Connection Buildup

Hardware faults on the 24 V DC load circuit side are indicated as follows:
• By flashing LEDs on the IP 265 ( Appendix A.1)
• By error bits set in the status word of the IP 265 ( Appendix A.2)
Table 3-1. Indication and Effects of Error Conditions
Hardware Fault
• Absence of 24 V DC power
supply
• Short-circuit between a 24 V
output and ground
• Short-circuit between two
outputs
• Ground conductor interrupted
(L+wire of 24 V DC supply
connected, M wire is
interrupted or not connected)
Warning
!
In the case of a break in the ground connector, voltages up to 7 V can be output at the
24 V digital outputs in the case of high-impedance loads.
3-6
Error Message
• STOP LED flashes
• I/O error bit set in the
status word
• STOP LED flashes
• RUN LED: Steady light
• I/O error bit set in the
status word
• None
• STOP LED flashes
• I/O error bit set in the
status word
• All 8 LEDs for 24 V
outputs: Steady light
Effects
• IP 265 goes into the STOP
mode
• IP 265 still in the RUN mode
• Affected short-circuited 24 V
outputs are disconnected and
set again after elimination of
the short-circuit
• None
• The IP 265 enters the STOP
state
• 24 V digital inputs are not read
• 24 V digital outputs are reset
EWA 4NEB 812 6130-02a
IP 265