Mitsubishi Electric NZ2MFB2-16A User Manual page 93

When output is turned on, load connected to other outputs is turned on simultaneously
■Cause
When a non-wiring state occurs due to, for example, a shutoff or disconnection between 0V of the external power supply and
the common of a load, a current flows across the load that is off through an unexpected circuit of the output element that is off.
Output module
Source output
ON
Output control
circuit
OFF
Output control
circuit
Continuous use in this state may cause failure.
■Action
Connect the external power supply with the load correctly.
To prevent the state described above, install diodes in each output terminal as shown below.
Source output
Load
Y0
Load
Y1
COM+
24VDC
CTL-
A load inputs data incorrectly due to a chattering.
■Cause
A device with a high input response speed is connected to the contact output module.
■Action
Use a transistor output module.
Load
Y0
Load
Y1
Shutoff or disconnection
COM+
24VDC
CTL-
11 TROUBLESHOOTING
11.4 Examples of Troubles with the I/O Module
11
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