Nautel XR12 Installation Manual

Also see for XR12: Troubleshooting manual Operation and maintenance manual Preinstallation manual

XR12 Installation Manual Control and monitoringPage 9-6 Issue 3.0 2009-07-15Remote control circuits and alarmsYou can control the active (A/B) exciter, the on/off status of the RF power stage, the preset RFpower level, the power level adjustment, and system alarm reset remotely. The remote interface PWBcontains a selection circuit that lets you select internal (single ended input) or external (differentialinput) input for all controlled functions.The external control circuits interface with the transmitter through opto couplers on the remoteinterface PWB. The opto couplers buffer and isolate the external circuits and prevent any unwantedtransients from affecting transmitter operation while remote control is selected at the transmitter.The switching circuits for the remotely controlled functions must be the equivalent of a normallyopen (momentary) switch. The switches must be configured to operate as a single-ended input usingthe transmitter's 24 V dc as the source, or as a differential input using an external dc power supply (24- 30 V). Each control function has negative inputs on the remote interface PWB. The positiveexternal +24 V IN input (TB1-3) is used by all control functions.Option 1 - Single Ended Input (Internal V dc). When you use the transmitter's 24 V as thecurrent source for a control function's opto coupler, configure the circuit on the remote interfacePWB for a single ended input. The SINGLE/DIFF 3-pin header (E19) must have its 2-socket shuntpost connected between pins 2 and 3 to configure the circuit.Figure 9.1: Single-ended Input SelectedA negative logic (active state is a current-sink-to-ground) command must be applied to the control'snegative (-) input. To avoid a ground loop, obtain the ground from TB1-18.3 PWB1 2+24VE19 SINGLES1830900 V1+24 V IN(TB1-3)INTERFACEREMOTEREMOTE SELECTION CIRCUITRYCONFIGURED FOR INTERNALDC VOLTS18