2-Phase 2-Input [C251 To C255] - Mitsubishi Electric MELSEC-F FX3G Series User Manual

FX Series Programmable Controllers
3G
User's Manual - Hardware Edition

11.8.2 2-phase 2-input [C251 to C255]

The following examples of wiring apply to the cases where C251 is used. When another high-speed counter
number is used, wire the counter referring to the following diagrams.
It is recommended to use shielded twisted-pair cables for connection cables. Ground the shield of each
shielded cable only on the PLC side.
1) NPN open collector transistor output rotary encoder
In the case of sink wiring
PLC
* The grounding resistance should be 100Ω or less.
2) PNP open collector transistor output rotary encoder
In the case of source wiring
PLC
* The grounding resistance should be 100Ω or less.
170
Fuse
L
N
Class D
grounding*
S/S
0V
24V
X000
X001
Fuse
L
N
Class D
grounding*
S/S
0V
24V
X000
X001
11.8 Examples of External Wiring (Rotary Encoder)
Rotary encoder
24V DC
24V
0V
Phase A
Phase B
Phase Z
Rotary encoder
24V DC
24V
0V
Phase A
Phase B
Phase Z
11 Use of High-speed Counters