Interconnection using 10base2 (coaxial) wiring – Fluke NetDAQ 2645A User Manual
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2640A/2645A NetDAQ
Users Manual
2-48
Interconnection Using 10Base2 (Coaxial) Wiring
2-41.
P
Caution
Connect the ground lug on the 50-Ohm terminator to the
instrument ground terminal only when there is no other
shield ground connected for the network.
10Base2 interconnection uses 50-Ohm coaxial cables (Belden 9907 or equal) that
loop between equipment items and connect at each station through a BNC "T" or
"Y" connector. Each network endpoint terminates into a 50-Ohm load. The
minimum distance between BNC T connections is 20 inches (0.5 meter) and the
total cable length (without repeaters) must not exceed 600 feet (185 meters).
Complete the following procedure to interconnect the instruments and host
computer using 10Base2 coax (Figure 2-31).
1.
Connect a BNC T or Y to the 10Base2 port on each instrument and on each
host computer.
2.
Connect approved Ethernet cables (for example, Belden 9907) with BNC
connectors to each BNC T or Y. Be sure you are using 50-Ohm cable!
3.
Connect 50-Ohm terminators to the BNC T and Y end points. Be sure you
have installed 50-Ohm terminations even if there is a direct connection
between the host computer and a single instrument. The instrument 50-Ohm
terminator at the network endpoint has a ground wire that is connected to the
instrument ground terminal (adjacent to the BNC connector) only when there
is no other shield ground connected for the network. (See Figure 2-32.)
Interconnection Using 10BaseT (Twisted-Pair) Ethernet Wiring
2-42.
The instruments support connection via twisted-pair Ethernet, usually in
conjunction with a "hub" for multiple instruments (See Figure 2-33). Take care
that you use twisted pair wires designed for 10BaseT network use (phone cables
will not work). Refer interconnection issues to your network administrator. (See
Appendix I, "Network Considerations.")
Direct connection between a single host computer and a single instrument with
10BaseT is possible, but you must use a special cable that has its transmit and
receive lines crossed. (See Figure 2-32.)