Individual tests
5.4 Line
impedance
The CANcheck determines the line impedance via a method of approximation.
Plug-in connections, stub lines and connected CAN nodes may falsify the test re-
sult.
The CANcheck checks whether the line impedance is in the tolerance range. The
tolerance range for the line impedance is given in 10.1.
For the test of the line impedance, please remove one of the two termination re-
sistors of your CAN network and connect the CANcheck in its place. Please switch
the CAN network off before the test. In addition, you should disconnect all CAN
nodes from the network. Switched off CAN nodes with a high resistance between
CAN_H, CAN_L and ground can remain connected. As the resistors of all con-
nected CAN nodes are parallel, however, the resistance of each individual CAN
node must then be greater than the "number of CAN nodes" x 1 k
Ω
.
Please select the menu item "Line impedance" with the keys UP and DOWN and
press the OK key.
Individual tests
▼
-Wiring test
-Term. resistors
-Line length
-Line impedance
-Power supply
-Baudrate detection
When the CAN network is switched off, the test instructions appear. Error mes-
sages are explained in 6. When you have followed the test instructions, please
start the test with the OK key.
During the measurement, a message appears. After the measurement, the test
result appears.
Line impedance
-Disconnect all nodes
-Remove termination R
on both ends
OK Start test
Copyright IXXAT Automation GmbH
CANcheck Manual, Version 1.2
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