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Does the low Speed CAN network need termination


resistance on every device? I have a PCI-CAN/LS card installed on my computer and I tried to send frames on the network with interact*.vi from NI-CAN library in LabView. Every time I get either a write error if I'm using the NEtwork Interface Object
or a read error if I use a CAN object previously
configured with NI-CAN Config. My card is internally powered and is using a resistance of
510 ohm for termination (the default). On the other end of the bus there is also a 120 ohm res.. I have two devices on the network. Do I
have to terminate them as well? I tried to
notice signal on the bus when I send frames
but there is no..
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Every Device on the low-speed CAN network requires termination resistor for each CAN data line: Rth for CAN_H and Rtl for CAN_L.The tranceiver on the NI CAN cards is a Philips tranceiver and Phillips recommends an overall Rth andRtl termination of 100 to 500 ohm ( each) for a properly terminated low-speed network and an individual device Rth and Rtl termination of 500 ohms to 16Kohms.The PCI CAN /LS board ships with the 510 ohm resistors, but also includes 15k resistors in the kit.
Please refer to the "Getting Started with the NI CAN hardware" manual , Appendix D ( Cabling Requirements for Low Speed CAN) on a detailed description on determing which resistor value is more appropriate for your low speed application.
The link to the manual is given below:

http://search.ni.
com/search/query.html?col=alldocs&qp=%2Bcontenttype%3Aproductmanual&lk=2&layout=ProductManual&qt=CAN
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