Mitsubishi Electric NZ2MFB2-16A User Manual page 91

■Action
Take either of the following two actions:
• Action 1: To suppress the back EMF, connect a diode parallel to the load where back EMF is generated in [3].
[3]
Sink output
+ Back electromotive force -
Load
• Action 2: Configure a sneak current path by connecting a diode across positive and negative of the external power supply.
When simultaneously taking an action for the case where load is briefly turned on when powering on the external power
supply, connect the diode in parallel with C1 and R1 as shown in the frame of dotted line.
+ Back electromotive force - [3]
Sink output
Y0
ON
Y1
OFF
COM-
C1 R1
CTL+
Example 1
- Back electromotive force + [3]
Source output
Y0
ON
Y1
OFF
COM+
C1 R1
CTL-
Example 1
D1:
*1
Reverse voltage VR (VRM)
*2
Forward current IF (IFM)
*1 Approximately 10 times as large as the rated voltage in the specifications
Example: 24VDC  Approximately 200V
*2 Twice as much as the maximum load current (common) in the specifications or more
Example: 2A/1 common  4A or more
Load
[2]
Load
[1] Shut off
D1
Load
[2]
Load
[1] Shut off
D1
Source output
- Back electromotive force +
Load
11.4 Examples of Troubles with the I/O Module
11 TROUBLESHOOTING
11
89