Vista LM104-P50 Option 5 Power line carrier transceivers, Option 6 Free Topology Transceiver

Option 5 – Power line carrier transceivers

These modules are designed to be used with couplers that interface between the node and the power line. As such, the PLT-22 transceiver and the power line coupler handle any termination issues. Any standard 50W BNC cable may be used to connect the LM105-P50 to its line coupler. Because the transmission medium is existing power line cable, the user will usually not have a choice in what cable is used. The PLT-22 compensates for this by operating at a much lower data rate than other transceivers (5Kbps).

Option 6 – Free Topology Transceiver

Free topology networks require only one terminator per network segment. It may be located anywhere in the segment, regardless of the topology. For Option 6 boards connected in a strictly bus-type topology, a second termination network may be added which will nearly triple the allowable network length. The circuit in Figure 3 will properly terminate a Free Topology network. Jumper JP3 must be left open to disable the LM104-P50’s onboard termination.

100mF, 50V

105W, 1%, 1/8W

100mF, 50V

Figure 3. Free topology network terminator circuit.

Free topology networks have the widest choice of qualified cable types. Like twisted pair transceivers, 22AWG (0.65mm) Level IV cable and standard TIA 586A Category 5 network cable may be used. Echelon has also certified Belden 8471 (PVC insulation) 16AWG (1.3mm) cable and Belden 85102 (Tefzel insulation) 16AWG (1.3mm) cables for use with free topology networks. A European standard cable, JY (st) Y 2x2x0.8, also meets Echelon’s rigorous standards.

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