Mitsubishi Electric MELSEC FX2NC-16MT-D/UL - Diodes and Inputs Connected in Series

FX2NC Series Programmable Controllers Inputs 5.
5-6
5.1.3 Diodes and inputs connected in series;
Vdrop across the diode Max. 4V
No more than 2 LEDs should be connected in series.
Figure 5.4 : Series diodes
FX
2NC
Main unit
FX
2NC
Extention
block
X
COM
COM
FX
0N,
FX
2N
Extention block
X
S/S
Ex. Sink