ipf electronic PY740020, Руководство пользователя

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MANUAL [ PY740020/21 ] • Subject to alteration! Version: 10.10.2018
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Example:
A 10m long line has a resistance of approx. 1Ω. The sensor draws a current of 90mA. According to Ohm's law,
the following voltage drop occurs at RL1:
URL1 = RLine * ICC
URL1 = 1Ω * 90mA = 90mV
In this example, the U-Out is increased by 90mV.
Tip:
Many measuring inputs can, however, only be operated with 0…10V. Using a simple trick, 2...10V can,
according to Ohm's law, be generat ed from 4...20mA with a resistance of 500Ω (parallel switching of two RM
resistances of 1000Ω). That way the effect can be avoided.
U
RL1
Sensor
=
≈
0V
+24V
I-Out
U
I
CC
U
RL1
Power
supply
Measuring
input
Line resistance R
L
R
L1
R
L2
R
L3
R
M
R
M