Mitsubishi Electric MELSEC-L Series User Manual page 81

(5) The load operates due to powering on the external power supply (transistor
output).
• The polarity of the external power supply is connected in reverse.
Cause
• When the polarity is connected in reverse, current may flow across an output element protection diode.
Action Connect the polarity correctly.
(6) The load operates by incorrect input due to chattering of the external power
supply.
Cause The device whose input response speed is too fast is connected to the contact output module.
Action Use a transistor output module.
Case
Transistor
output module
Load
Y0
Incorrect
External
power
supply
COM
Output element
protection diode
Case
CHAPTER 8 TROUBLESHOOTING
Correct
8
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