Mitsubishi Electric MELSEQ FX3S Series User Manual page 85

FX Series Programmable Controllers
3S
User's Manual - Hardware Edition
3. In the case of input device with built-in parallel resistance
Use a device having a parallel resistance, Rp, of 15 kΩ or more.
If the resistance is less than 15 kΩ, connect a bleeder resistance, Rb (kΩ), obtained by the following formula
as shown in the following figure.
4Rp
Rb (kΩ) ≤
15-Rp
24V
S/S
PLC
(Sink input)
0V
4. In the case of 2-wire proximity switch
Use a two-wire proximity switch whose leakage current,
When the current is larger than 1.5 mA, connect a bleeder resistance, Rb (kΩ), determined by the following
formula.
Rb (kΩ) ≤
I -1.5
24V
S/S
PLC
(Sink input)
0V
Bleeder
resistance
Rb
X
15 kΩ
Rp
or more
6
Bleeder
resistance
Two-wire
Rb
I proximity sensor
X
9.2 24 V DC input (Sink and source input type)
0V
S/S
PLC
X
(Source input)
15 kΩ
or more
24V
I
, is 1.5 mA or less when the switch is off.
0V
S/S
I
PLC
X
(Source input)
24V
9 Input Wiring Procedures
Bleeder
resistance
Rb
Rp
Bleeder
resistance
Two-wire
Rb
proximity sensor
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