Carrier 48FK specifications Inlet Guide Vane Motor 50FK,JK034-074 Units

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Supply Fan Control with IGV Option Ð The inlet guide vane option will modulate the supply fan air¯ow in order to maintain the static pressure in the supply duct. The set point for duct static pressure is established at the differ- ential pressure switch for the IGV control.

SIZE 034-048 UNITS Ð The inlet guide vane differential pressure switch is located in the auxiliary control box mounted in the corner under the side air hood that is next to the access door marked FILTER SECTION. To gain access to this con- trol box, remove the auxiliary control box cover. When replacing cover, be sure to properly secure it in order to prevent water from being drawn into the unit. See Fig. 36 and 37.

SIZE 054-104 UNITS Ð The inlet guide vane differential pressure witch is mounted on an upright located behind the supply-fan motor. See Fig. 36-38.

The IGV differential pressure switch has an adjustable set point range of 1.1 to 3.5 in. wg. and a factory setting of 1.9 in. wg.

To adjust set point, turn set point adjusting screw (see Fig. 39) clockwise to decrease set point and counterclock- wise to increase set point. This switch also has an adjustable null span. The null span is the pressure change that can be made without contacts opening or closing. It is adjustable from 0.06 in. wg to 0.17 in. wg when set point is at mini- mum position (1.1 in. wg) and 0.11 in. wg to 0.31 in. wg when set point is at maximum position (3.5 in. wg). To ad- just null span, turn a null adjusting screw (Fig. 39) clock- wise to decrease span and counterclockwise to increase span. All switches leave factory with null span set at maximum position. The smaller the null span, the closer the pressure will be maintained to desired set point.

Supply Fan Control with VFD Option Ð The VFD option will modulate Supply Fan motor (and thus wheel) speed to maintain the static pressure in the ductwork. Set point for the VFD option is set at the VFD, using the display key- board on the front of the VFD enclosure. See Fig. 40.

NOTE: The VFD will always provide the proper phase sequence to the supply-fan motor. The supply-fan motor op- erates in proper rotation regardless of the phase sequence to the unit. If, upon start-up, the outdoor fans operate back- wards but the supply fan operates in the correct direction, reverse any two leads to the main terminal block. All fans will then operate in the correct direction.

To set the duct static pressure, perform the following steps. The factory setting is 2.5 in. wg. The duct transducer has a range from 0 to 5 in. wg. The transducer output is 4 to 20 mA, therefore, 0 to 5 in. wg is proportional to the 4 to 20 mA and must be expressed to the VFD in terms of per- centage of the frequency range. Refer to Table 13. The set point value is a percentage of the maximum output fre- quency. Locate the duct static pressure closest to that de- sired and use the corresponding set point value. If necessary, interpolation between duct static pressures is permissible.

Factory-installed optional VFD is located near the sup- ply fan and motor. During any service work or pro- gramming at the VFD, operation of the fan and motor is not desirable and may be dangerous. Either disable the unit supply fan (following instructions below) or in- stall the accessory VFD remote display accessory.

*The inlet guide vane differential pressure switch for the 034-048 units is located in the back of the unit in the auxiliary control box. Its lo- cation is not shown in this ®gure.

Fig. 36 Ð Inlet Guide Vane Motor,

50FK,JK034-074 Units

*The inlet guide vane differential pressure switch for the 034-048 units is located in the back of the unit in the auxiliary control box. Its lo- cation is not shown in this ®gure.

Fig. 37 Ð Inlet Guide Vane Motor, 48FK,JK, 50FY,JY,

and 50FJX,FJY,FKX,FKY034-074 Units

Fig. 38 Ð Inlet Guide Vane Motor,

Size 078-104 Units

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Contents Controls Operation Troubleshooting ContentsSafety Considerations GeneralPin Terminal Connector J1 Thermistor Inputs Connector J1 Temperature Unit Size Terminal no InputDIP EXVStatus Switch Inputs Connector J2 Status Switch Unit Size Terminal no034-104 RNT Ð ReturnPage Output Pin and Terminal Assignments Output PIN Name Rating Device TerminalHIR IFCCompressor Operation Thermistor T1 Location, 50FK,JK034-048 Units Thermistor T1 Location, 50FK,JK054-074 Units Thermistor T2 Location, Size 034-048 Units Thermistor T3 and T4 Locations, Size 054-104 Units Integrated Circuit InputControls Installation Space Temperature ResetUnit Control Box Arrangement, Sizes Unit Control Box Arrangement, Sizes Unit Control Box Arrangement, Sizes 088 Voltage Drop Characteristics Thermistor ResistanceSpace Temperature Sensor Averaging Single-Step Demand Limit MSP = Sasp + Remote Sasp Wiring Smoke Control Switches Required for Each Mode Smoke Control ModesSwitch Functions Tubing SizeSwitch DPS Ð Differential Pressure SwitchTerminal Block Modulating Power Exhaust Differential Pressure Switch Sizes START-UPPotentiometer Inputs and Ranges Conguration Header DIP Switch Factory SettingsConguration Header Jumpers DIP Switches Switch Function Meaning PositionInlet Guide Vane Motor 50FK,JK034-074 Units Jumper Removal to Disable Motor Variable Frequency Drive KeypadVFD Set Point Frequency Command for Duct Pressure Changing the VFD Set Point Frequency CommandControl Signal Pressure VFD SET Point PressureStart Unit Quick Test, Unit Conguration and Switch Check Quick Normal Description Control Switch Test Display Step noQuick Test, Thermistor and Potentiometer Check Quick Test, Output Relay CheckQuick Normal Description Thermistor or Test Quick Normal Test Description Relay NumberOperating Information Sensor Resistance ValuesPage Component Arrangement, 034-048 Units Component Arrangement, 054-104 Units Page Modulating Power Exhaust Component Locations Sizes Modulating Power Exhaust Component Locations Sizes Page Compressor Loading and Unloading Sequences Cooling Size 054 Units Cooling Size 064 UnitsCooling Size 088 Units Cooling Size 104 UnitsTroubleshooting Controls TroubleshootingSymptoms Probable Causes Solutions Operation Status CodesDiagnostic Codes Codes 71 to 76 THERMISTOR/RESISTOR Failure Page Terminals Voltage AC Test PIN Voltage DC TP3TP4 TP6Quick Test J9 PIN Numbers Step no PIN Terminal Voltage DCPin Terminal Connector J1 Voltages Pin Terminal Connector J2 VoltagesTerminal Strip J6 Connection Resistance Reading PIN Voltage TerminalEnthalpy Sensor Checkout Terminal Strip J5 Connector Resistance ReadingQuick Test J5 PIN Numbers Step no Variable Frequency Drive Carrier Default Program Parameter Values Parameter Group Default ValueRequired User Adjusted Defaults Motor Overload SettingsALM LATLPS MTRPage Page Service Training Call for Free CatalogII. Preliminary Checklist Items PRE-START-UPIII. START-UP IV. Notes