Delta DCS

53
6. DESCRIPTIONS FOR TROUBLESHOOTING
E?500 STO function is activated
Cause
Safety function STO is activated.
Check and Correction
Safety function STO is manually activated; please check the activating cause.
Solution
Reset alarm.
E?501 STO_A lost
Cause
STO_A loses enabling signal or STO_A and STO_B have not been synchronized
for more than 1 second.
Check and Correction
Whether the STO_A wiring is correct.
Solution
Reset alarm.
E?502 STO_B lost
Cause
STO_B loses enabling signal or STO_A and STO_B have not been synchronized
for more than 1 second.
Check and Correction
Whether the STO_B wiring is correct.
Solution
Reset alarm.
E?503 STO_error
Cause
STO self-diagnosis error.
Check and Correction
Whether STO_A and STO_B correctly connected.
Solution
Reset alarm.
E?555 Drive failure
Cause
Drive processor abnormal.
Check and Correction
Do not make any modification on the original machine if this alarm occurs; return
it to the original manufacturer directly.
Solution
None.
Note: If abnormal alarm code that isn’t listed above, please notify the original manufacturer.