2 electrical potential conditions – Baumer BA_DSRT_22DJ Benutzerhandbuch
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Manual_CANopen_StrainLink_EN_V3_05.doc
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3.2 Electrical potential conditions
The electrical potential conditions of a CAN bus system with a CANopen strain link are characterized by the
following features:
•
The CAN bus connection is not potentially isolated from the supply connection
•
The individual CANopen strain links are not electrically isolated from the supply voltage
•
Every CANopen strain link can be powered separately
Avoid differences in electrical potential by
•
connecting every CAN user to the same ground reference potential (PE) of the machine/system
via the shortest path with the lowest resistance possible.
•
using a potential equalization line between the communications users.
•
connecting the ground reference for the machine/system to the main ground via a low resistance
path.
Recognizing EMC noise in the signal oscilloscope display
Oscilloscope displays of the CAN signals (1) with and (2) without noise voltage (measuring points:
CAN_HIGH to CAN_LOW).
To quantify the noise, measurements with a CAN analyzer are necessary. With this device, important bus
parameters such as the bus load or the number of error frames can be determined and more in-depth
analyses performed.