Contemporary Control Systems AI Active Hubs - Manual (Page 26)

TD675100-0M
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Figure 2-16. Data Rate Switch
NOTE: On -485X models data rates less than 1.25 Mbps are
not supported.
2.8 Supporting Extended Timeouts
Although seldom used, ARCNET networks can be configured
for extended timeouts to facilitate geographically larger
networks. In this situation, each network interface module must
be configured for the same timeout. The AI will work with
either of the four available timeout settings, but the RECON
indicator will function unreliably if the reconfiguration detection
circuitry is not configured for the same timeout as the network.
There are four jumper settings on the AI to accommodate
extended timeouts. On the board is jumper setting E1. The
jumper can be found installed in the NORM position. This is the
factory setting and the default setting for standard ARCNET
networks which is the shortest setting. The next available
setting is marked ET1, the next longest is ET2 and the longest is
ET3. Simply move the jumper to the desired position. With
newer ARCNET controller chips, the reconfiguration timers are
programmable and there may be no appropriate timeout setting.
To disable the RECON light, remove any jumpers from NORM,
ET1, ET2 or ET3.