Hunter Control System Design Guide - Hunter Industries

Modem Central SystemsModem central systems are actually a form of TriSend central interface communications, butallow the central computer to operate one or more sites remotely via telephone lines. The centralcomputer dials remote modem-equipped TriSend centrals and operates radio and/or hardwirecontrollers at distant locations.In modem centrals, no central interface is installed at the computerʼs location. Instead, theTRISENDRMOD remote central interface is installed at the remote location. A modem centralsystem uses the internal modem in the central computer to dial TRISENDs at the remotelocations. At the remote location, the TriSend communicates via radio and/or hardwire to thelocal Field Controllers. Additional locations only require an additional TRISENDRMOD. TheTRISENDRMOD plugs directly into a telephone line (standard RJ11 telephone jack), andconnects to the hardwire Field Controllers via GCBL, like regular hardwire systems, or radiocontrollers through an RA5M antenna.Existing TriSend central interfaces can be upgraded to modem communications by ordering andinstalling TRIMODKT modem kits, and connecting to a telephone line.This allows the operator to dial-up a remote location from the computer, communicate with theField Controllers when necessary, and then hang up and dial another location. The computer doesnot need to be “on line” with each system to irrigate, because the field resident memory in theField Controllers runs irrigation schedules on its own. The remote system can be any distancefrom the central computer, as long as there are telephone connections at either end.The TRISENDRMOD is in a steel wall-mounted cabinet and may be mounted outdoors. It containsits own modem and the communication outputs, in a single enclosure. This enclosure shouldbe mounted within 25 feet of a direct telephone line connection. Radio versions require an RA5Mbase antenna and, of course, an FCC license.It is strongly recommended that TriSend modem communications are connected to a dedicatedtelephone line. This prevents the system from experiencing busy signals when communicationsmay be needed.Genesis ® and VSX radio controllers both support Straight Talk Maintenance Radio commandsregardless of the installation type, and hardwire systems have a Maintenance Radio interfacebuilt in to the TriSend even in remote modem applications.Site A with TRISENDRMODCentral control pointwith dial-up connectionsSite B with TRISENDRMOD14