Omron GX-AD0471, User Manual, Page: 381 / 394

A - 77
A Appendix
GX-series EtherCAT Slave Unit User’s Manual
A
-3 Precau
tion
s with
Con
n
ect
ing
T
w
o-
wire D
C Senso
rs
A
A-3
-3 Relation betwe
en OF
F C
urre
nt of a Unit with DC I
nputs and Sensor Leakage C
urre
nt
I
OFF
≥
I
leak
I
OFF
: OFF current of a 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
Unit
with
DC inputs.
The bleeder resistor constant can be calculated using the following equation.
R
≤
(I
OFF
×
R
IN
+ V
F
) / (I
leak
- I
OFF
)
Power W
≥
(V
CC
−
V
R
)
2
/ R
×
4 [allowable margin]
A-3-3 Relation between OFF Current of a Unit with DC Inputs and
Sensor Leakage Current