Re: Experience with Star Quad cable for CAN bus



On Oct 6, 1:57 pm, Stef <stef...@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
wrote:
Does anyone here have experience with Star Quad cable for CAN bus
communications (or any data communication)? We ordered the assembly of
some cables for a CAN network in a noisy machine environment and requested
2x2 shielded twisted pair cable, one pair for H/L and the other will be
used for ground, shield connected to the connector shells.

Today our supplier asked if he could use a different kind of cable. This is
a cable especially made for CAN ("CAN" printed on the purple insulation, 120
ohm impedance), but it's not 2 twisted pairs but a single quad. I have no
experience with this kind of cable and a web search turns up mostly audio
for "star quad".

If I search cable manufacturer websites, they always come up with 1/2x2
shielded cable for CAN bus.

Our bus will be aprox. 40m, 500kbit/s and the environment is noisy.

Star Quad cable has higher capacitance than the standard twisted-pair
cable, so one might expect reduced signal rise times and maximum cable
length. I don't know if CAN has any specs regarding cable capacitance.

-a
.



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