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Product Description

The Model 8242 is a fiber optic modem for use in multi-point applications from office to factory environments. The fiber optic capability protects both the data and the hardware from the effects of EMI/RFI and Lightning/Surges that are found in many commercial environments. The multi-point feature is implemented by providing dual fiber transmit and receive ports to accommodate primary communications from one side to the secondary communications port on the other. Five operating modes allow the Model 8242 to operate as a Single Master, Dual Master, Point-to-Point, Broadcast or Link Extender.

In the Single Master Mode the master station sends polling sequences to addressable slave stations. The response of the addressed station is only received by the master station. In the Dual Master Mode one supervising station is connected at each end of the multi-point link. The supervisory station at site A is designated the master station. The station at the other end is designated as the backup master station. Each addressable slave station can be polled from the backup station in the event that the master fails or the line is dropped. The response from the addressed station is received by all other stations.

The Model 8242 is available with any one of three different peripheral electrical interfaces; Model 8242-1 for RS-232, Model 8242-2 for RS-422 and as the Model 8242-3 for RS-485. The electrical interface appears on the terminal strip located on the upper edge of the unit. The RS-485 can be switch selected for 2 or 4 wire operation. The power input is also available on the terminal strip since the Model 8242-X incorporates its own power supply. The basic unit is 110 Volt, 60 Hz, with 220 Volt, 50 Hz being available as an option.

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