Checking The Termination - GO Systemelektronik BlueBox T4 Manual

B l u e B o x

4.4 Checking the Termination

Please take notice of the correct termination of the
single modules to assure a correct performance of
the CAN-bus.
The termination can be controlled by measuring
the resistance between CAN-High and CAN-Low
with a multimeter.
The measurement can be done at any device of the
CAN-bus-system.
The easiest way to measure this resistance is un-
derneath the spring clips. That is the reason why it
is advisable to measure at modules with clamps.
The measuring procedure is described in the fol-
lowing:
Consider that the modules that are going to be
proved are without voltage, i.e. the power supply
of the BLUEBOX has to be switched off.
Measure the resistance between CAN-High and
CAN-Low as it is shown in the illustration.
The measured value should be between 55 Ω and
70 Ω. At the following divergence the respective
errors are:
0 Ω short circuit in line
< 55 Ω more than one module terminated
120 Ω
only one termination
(for example, only the BlueBox is
terminated)
>120 Ω
no module is terminated or
cable break
GO Systemelektronik GmbH Faluner Weg 1 24109 Kiel
www.go-sys.de
correct termination
Germany Tel.: +49 431 58080-0
info@go-sys.de
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