Carrier 50HC Series Service And Maintenance Instructions

Also see for 50HC Series: Installation instructions Installation instructions

34switches allow you to select your protocol (and baud rate) ofchoice among the four most popular protocols in use today:BACnet, Modbus, Johnson N2 and LonWorks.The RTU Open control is factory--mounted in the unit’smain control box, to the left of the Light CommercialTerminal Board (LCTB). Factory wiring is completedthrough harnesses connected to the LCTB. Fieldconnections for RTU Open sensors will be made at thePhoenix connectors on the RTU Open board. Thefactory--installed RTU Open control includes thesupply--air temperature (SAT) sensor. The outdoor airtemperature (OAT) sensor is included in theFIOP/accessory EconoMi$er2 package.SENSORY/ACCESSORYINSTALLATIONThere are a variety of sensors and accessories availablefor the RTU-OPEN. Some of these can be factory or fieldinstalled, while others are only field installable. TheRTU-OPEN controller may also require connection to abuilding network system or building zoning system. Allfield control wiring that connects to the RTU-OPEN mustbe routed through the raceway built into the corner post ofthe unit or secured to the unit control box with electricalconduit. The unit raceway provides the UL requiredclearance between high and low-voltage wiring. Pass thecontrol wires through the hole provided in the corner post,then feed the wires thorough the raceway to theRTU-OPEN. Connect the wires to the removable Phoenixconnectors and then reconnect the connectors to the board.IMPORTANT: Refer to the specific sensor or accessoryinstructions for its proper installation and for rooftop unitinstallation refer to base unit installation instructions andthe unit’s wiring diagrams.ELECTRICAL SHOCK HAZARDFailure to follow this warning could result in personalinjury, death and/or equipment damage.Disconnect and lock--out/tagout electrical powerbefore wiring the RTU--OPEN controller.! WARNINGADDITIONAL RTU--OPENINSTALLATION ANDTROUBLESHOOTINGAdditional installation, wiring and troubleshootinginformation for the RTU--OPEN Controller can be foundin the following manuals: “Controls, Start--up, Operationand Troubleshooting Instructions,” and “RTU OpenInstallation and Start--up Guide.”50HC