Carrier 30GX Installation, Operation And Maintenance Instructions

Also see for 30GX Series: Installation, operation and maintenance instructions Installation, operation and maintenance instructions

22Item 4 Demand limit contact statusWhen closed this contact limits thedemand of the unit by reference to thevalue of the demand limit setpoint, if thecontact method of demand limit has beenselected (see section 4.2.10).• Contact open: unit demand not limited• Contact closed: unit demand limited tothe limit setting.See section 4.2.7 for a description ofdemand limit setting and section 3.4.9 fora description of reduction contact con-nections.NOTE: This contact is active in all operating types.Item 5 Interlock check contact statusWhen this contact opens the unit stops or isprevented from starting and an alarm iscreated. In general the contact is used tocontrol the evaporator water flow.See section 3.4.8 for a description of theconnection for the lockout contact.NOTE: This contact is active in all operating types.Item 14 External 0-10 V d.c. signalThis signal, which is from an externalsource, can be used (depending on theconfiguration) for:• The reset function• Demand limit of the unitSee section 4.2.10 for the configuration ofthe signal. See section 3.4.10 for a descrip-tion of the connection for the 0-10 V d.c.signal.NOTE: This contact is active in all operating types.Item 0 Remote start/stop contact statusThis contact is used to select thefollowing modes of operation when theunit is in remote operating type (rEM):• Contact open: unit stop command• Contact closed: unit authorised to start up.See section 3.4.5 for a description of theconnections for the remote start/stopcontact.Item 1 Remote cooling setpoint selection contactstatusThis contact is used to select a coolingsetpoint only when the unit is in coolingmode and remote operating type (rEM):• Contact open: unit using cooling setpoint1• Contact closed: unit using coolingsetpoint 2This command is inactive if the unit isoperating in heating mode.See section 3.4.6 for a description of theconnections for the remote coolingsetpoint selection contact.Item 2 Remote heat/cool selection contact statusThis contact is used to select heating orcooling mode only when the unit is inremote operating type (rEM):• Contact open: unit in cooling mode• Contact closed: unit in heating modeThis command applies to heat pumpsonly.See section 3.4.7 for a description of theconnections for the remote heat/coolselection contact.Item 3 Remote reclaim mode selection contactstatusThis contact is used to select the secondcondensing setpoint or reclaim mode(provided the unit is of the reclaim type)only when the unit is in cooling mode andremote operating type (rEM):• Contact open: unit using normalcondensing setpoint and in normalmode (no reclaim).• Contact closed: unit using reclaimsetpoint and in reclaim mode.See section 3.4.8 for a description of theconnections for the remote condensationmode selection contact.