AppendixB CablingRequirements for PXI-8460 Low-Speed CAN
PXI-846xand NI-CAN for Windows NT B-6 ni.com
Philipsalso recommends an individual device RTH and RTLtermination of
500 Ωto 16 kΩ.The PXI-8460 board ships with mounted RTH and RTL
valuesof 510 Ω±5% per port. Th ePXI-84 60 kit also includes a pair of
15 kΩ±5% resistorsfor each port. After determining the termination of
your existing network or device,you can use the followingform ula to
indicatewhich value should be placed on your PXI-8460 board in order to
producethe proper overall RTH and RTLtermination of 10 0to 500 Ωupon
connection of the board:
*RRTHoverall shouldbe between 100 and 500 Ω
**RRTHof low-speed CAN interface=510Ω±5%(mounted) or 15 kΩ±5% (in kit)
†RRTH =RRTL
Asthe formula indicat es, the 510 Ω±5% shipped on your board will work
withproperly terminated networks having a total RTH and RTLtermination
of125 to 500 Ω, or individual devices having an RTHand RTL termination
of 500 Ωto 16 kΩ.For communication with a network having an overall
RTHand RTL termination of 100 to 125 Ω, you will need to replace the
510 Ωresistors with the 15 kΩresistors in the kit. Please refer to the next
section, Replacing the Termination Resistors.
RRTHoverall*†
1
1
RRTHof low-speed CAN interface**
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RRTHof existing network or device
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