Thread: CAN Cables
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Unread 20-01-2011, 20:48
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Hugh Meyer Hugh Meyer is offline
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Re: CAN Cables

Only connect the two center pins. Pins 3 & 4. If you connect them all, one is a ground connection and will create a ground loop. The only signals needed are the CanHigh and CanLow. This is a balanced differential circuit, so no ground connection is required.

If you have a ground loop and one Jaguar has a heavy load and another does not this situation will cause noise. We smoked several Jaguars last year and after we disconnected the ground connection the system was much more stable.

The only cable that needs the ground pin connected is the serial cable that connects to the cRio or computer. The ground wire would only be required on the first Jaguar if you are using the serial port as your CAN gateway. If you are using a 2CAN or other outboard device then only connect the center two pins.

Be sure to have the 120 ohm terminator at the end of the line.

-Hugh
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