Thread: Magic 2CAN
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Unread 02-06-2012, 09:34 AM
jwakeman jwakeman is offline
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Magic 2CAN

We ran into an interesting feature of the 2CAN this weekend. The ability to be powered without a negative lead! One of the students told me that the 2CAN LED was still flashing despite the black wire (battery GND) falling out. I assured him that this was impossible and we continued working. Later he insisted on proving it to me and indeed he was correct! We proceeded to disconnect the CAN cable between the 2CAN and the Jaguar, the 2CAN turned off. We reconnected the CAN cable and disconnected the Jaguar battery ground wire, the 2CAN turned off. Based on these tests we decided the 2CAN was finding a path back to the battery through the CAN network cable and the negative lead on the Jaguar power connection. I attached an illustration for clarity. We were surprised to find out there is no isolation between the CAN network and the power electronics inside the Jaguar. Comments on this? Do we have a defective part, faulty wiring, or is this no surprise to some of you out there?
Attached Images
File Type: bmp Magic2CAN.bmp (1.47 MB, 40 views)
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