Omron CRT1 - 10-2009, Operation Manual

Page: 662 / 675

638
Precautions with Connecting Two-wire DC Sensors
Appendix D
Relation between OFF Current of Slave Unit with DC Inputs and
Sensor Leakage Current
I
OFF
≥
I
leak
I
OUT
: OFF current of a Slave Unit with DC Inputs
I
leak
: Sensor's leakage current
Connect a bleeder resistor if the Sensor's leakage current is greater than the OFF current of a Slave Unit with
DC Inputs.
The bleeder resistor constant can be calculated using the following equation.
R
≤
(I
OFF
×
R
IN
+ V
F
)/(I
leak
−
V
OFF
)
Power W
≥
(V
CC
−
V
R
)
2
/R
×
4 [allowable margin]