Premium/Atrium PLCs are connected to Jnet networks via a PCMCIA card.
Jnet networks are used to exchange data between Premium/Atrium PLCs and series 1000 April PLCs and SMC 500/600 PLCs.
A bus-type topology and deterministic token passing communication protocol are used.
The words exchanged make up a table. This table is stored in each PLC, and is broken down into as many zones as there are PLCs on the Jnet network. The zone assigned to each PLC may vary in size (defined on configuration).
The characteristics are as follows:
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Compatibility: April 2000/3000/5000/7000 - SMC50/600
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Number of PLCs: Maximum 32 (16 for an SMC-type network)
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Fixed transmission speed: 19200 Bauds
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Fixed transmission format: 8 bits, no parity, 1 stop
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Data transmitted: Maximum 128 words, shared between all PLCs (max. 64 words for a SMC-type network)
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Transmission media: Current loop or 2-wire RS485
NOTE: Jnet documentation is only available on the Technical documentation CD-ROM.
NOTE: Premium PLCs using Control Expert are connected to a Jnet network in very specific cases, on existing installations. Given that the functionalities are the same as for PL7, the documentation remains in PL7 format. You must therefore adapt it for use in a Control Expert environment.
