Parker PHD28, User Manual, Page: 23 / 157

User Guide 15
Inputs
3.3.1.1. Analog input connections
Analog inputs are susceptible to system noise, which can affect the accuracy of
the signal. Signal accuracy can also be affected by ground level shift, which can
cause inputs to activate when they shouldn't.
System noise
To prevent noise pickup on the sensors,
▪
Use the shortest possible wires when connecting analog inputs to sensors.
The following shows how to connect an analog input to reduce system noise:
Internal to product
+5 Vdc Sensor Supply
Sensor Ground
Sensor
Analog Input
Figure 6: Analog input system noise reduction
Ground level shift
To reduce ground level shift:
1. Dedicate one of the <Number GND> system ground inputs (GND) to sensors
that have dedicated ground wires, and connect all sensor grounds to this
system ground input.
2. Splice the other system ground inputs together in the vehicle harness (close to
the connector) to provide a better ground for the noisier low-side outputs and
digital circuits.