ACCESSORY KIT INSTALLATION INSTRUCTIONS Low Ambient Accessory For Air Cooled Split-System Air Conditioners YD360/480/600, YJ-30/-40/-50 and J30/40/50 YD Models 642546-UAI-A-080 GENERAL Standard operation of these split-system condensing units occurs at ambient temperatures down to 40 F. This low ambient controller ensures safe operation down to 0 F ambient temperatures. One controller is required per refrigeration system controlled. The Johnson Controls VFD66 Series Condenser Fan Speed Control regulates the speed of a three-phase condenser fan motor by varying the frequency and voltage of the power supplied to the motor. The VFD66 control accepts a signal from the P499 Electronic Pressure Transducer that provides a 0-5 VDC analog output signal.the signal varies depending on the pressure inside the refrigerant system discharge line. The VFD66 control allows the system to maintain optimum condenser head pressure in low ambient temperature conditions, eliminate short-cycling in low ambient temperatures or changing load conditions and match the condenser fan speed to the condenser load which increases the system efficiency. This can reduce energy usage cost and help maintain a constant evaporator temperature. The VFD66 control can also stabilize condenser head pressures which optimizes compressor operation and extends compressor life, eliminate condenser fan short-cycling which reduces motor repair and replacement costs and stabilize evaporator temperatures which provides more consistent comfort cooling. TABLE 2: ACCESSORY COMPONENTS ITEM QTY. PART NO. DESCRIPTION ea 773 (208/ 230V) 774 (460V) VFD66X Condenser Fan Speed Control and Enclosure 2 ea 257377 P499 Pressure Transducer 3 ea 8499 WHA-PKD3 Wire Harness Assembly 4 ea 8686 Power wire Harness 5 ea 6666 Tee Connector 6 2 ea 5829 Screw HEX ¼-4 X.75 7 ea 739 Bushing 8 6 ea 735 Wire Tie 9 ea 8493 0ºF Degree Switch 0 2 2 ea 3 3 ea 8422 30 Ton Crankcase Heater (208/230V) 8423 30 Ton Crankcase Heater (460V) 8424 40/50 Ton Crankcase Heater (208/ 230V) 8425 40/50 Ton Crankcase Heater (460V) 808 5A Fuse (208/230V) 98827 9A Fuse (460V). X denotes Model number needed for application. 2. Crankcase Heaters supplied are dependent on accessory ordered. 3. Fuses supplied are dependant on accessory ordered. TABLE : APPLICATION DATA ACCESSORY MODEL # VOLTAGE UNIT 2LA04703925 208/230 YD360, YJ-30, J30YD 2LA04703946 460 YD360, YJ-30, J30YD 2LA04704025 208/230 YD480, YJ-40, J40YD 2LA04704046 460 YD480, YJ-40, J40YD 2LA0470425 208/230 YD600, YJ-50, J50YD 2LA0470446 460 YD600, YJ-50, J50YD FIGURE - ACCESSORY COMPONENTS The 2LA047 series low ambient accessories are intended for use with 30-50 Ton Split System condensing units only. Unitary Products cannot guarantee proper operation for any application of this VFD 66X controller for other equipment or applications. Contact your local branch or distributor for any application related questions. Johnson Controls Unitary Products
Improper installation, adjustment, service or maintenance can cause injury or property damage. Therefore, only a qualified installer or qualified service personnel should perform this conversion. If the unit is connected to power sources, make sure that all electrical power to the unit has been disconnected.. Disconnect all electrical power to the unit. 2. Remove condensing unit control box access panel. 3. Remove compressor access panel. 5. Attach pressure transducer to tee connector (Item 5). The pressure transducer has a ¼ in. SAE female flare with Schrader valve depressor for mounting to the tee (See Figure 2). NOTE: Transducers should not be operated in a vacuum. Operating transducers in a vacuum for extended periods of time can cause damage. An allowable vacuum of 30 microns (0.03 mm Hg) is permitted short term. Transducers should be installed after refrigerant circuits are charged. Hand thread transducer to the tee. Tighten and secure the connection. Remove Schrader valve cap from discharge line port. Hand thread tee to discharge line port. Tighten and secure the connection, making sure the transducer is mounted vertically. See Figure 3. Perform a leak test on fittings and connections before putting the system into operation. 4. Install additional crankcase heaters (Item 0) on the compressors of the system to which the VFD66 control is being applied. Wire each additional heater parallel to the existing heater, utilizing the existing ground. Before installing accessory read all of this installation instruction. FIGURE 3 - P499 PRESSURE TRANSDUCER MOUNTING NOTE: This procedure must be repeated for each system. 6. Attach wiring harness assembly plug to (P499) transducer (See Figure 4). Route sensor wires to outside of unit. FIGURE 2 - P499 PRESSURE TRANSDUCER Do not remove the plastic plugs from the transducers until they are ready to be installed. FIGURE 4 - WIRE HARNESS ASSEMBLY 2 Johnson Controls Unitary Products
Diagnostic Light-Emitting Diodes (LEDs) Terminal Access Cover 6-/4 (59) 4-3/4 (20) Terminal Cover Screw FIGURE 5 - VFD ENCLOSURE & FAN MOTOR LOCATION 7. Close compressor compartment by reattaching access panel removed in Step 3. 8. Mount VFD66 enclosure with screws provided (Item 6). Holes are pre-punched in the unit top rails to locate the enclosure near the condensing unit control box. (See Figure 5). 9. Remove VFD66 enclosure lid. 0. Pass wires through the bushing (Item 7), using one of the knock outs located in the bottom of the VFD66 enclosure. 7-/2 (90) 7 (77) 3 conduit openings /2-in. trade size 7/8-in. (22 mm) actual size Heat Sink FIGURE 6 - VFD66 NEMA ENCLOSURE DIMENSIONS Jumper Blocks for Input Device Selection Input Device AC Power Input 4-5/8 (7) 7-/4 (84) /4-in. (6 mm) mounting screws, 4 places Output to Fan Motor Jumper Blocks for Circuit Adjusting Board VFD66 (cropped Control view). Access VFD66 control terminal blocks. See Figure 7. Remove terminal access cover screw. Push downward on the ventilation holes while pulling outward on the top of the terminal access cover. J7 J8 TB3 2 34 TB L3 L2 L TB2 T T2 T3 J5 J6 J2 J3 J4 J9 P P2 Conduit Entry Bracket Ground Connection Terminals Route wiring from input devices through this conduit entry hole. Potentiometers FIGURE 7 - VFD66 CONTROL TERMINAL BLOCKS 2. Cut hole in left-most bushing in the bottom of the VFD66 control. Push transducer sensor wires through this bushing (See Figure 6). 3. Wire transducer to terminal block TB3 VFD66 control (See Figure 8). Johnson Controls Unitary Products 3
NOTE: Maximum terminal tightening torque for all VFD66 controls electrical terminals is 5 in. lb. P499 Transducer Connect red wire to TB3 -. Connect black wire to TB3-4. Connect white wire to TB3-2. Connect bare wire to the grounding terminal. NOTE: Red White Black Input Devices Note: Route The Transducer Wiring Through The Left Conduit Hole On The VFD66 Control. FIGURE 8 - P499 PRESSURE TRANSDUCER WIRING All Wiring must comply with prevailing Local and National wiring codes and ordinances. Disconnect the power supply before making electrical connections. The printed circuit board and its components are at AC line voltage. Contact with components carrying hazardous voltage can cause electric shock and may result in personal injury or death. Conduit # should run from the bottom of the VFD66 enclosure to the condensing unit control box, using knock outs provided. NOTE: Use only stranded copper wire, rated for at least 600 volts. In conduit # insert three # 4 Gage wires marked on both ends (field supplied). Conduit #2 should run from the bottom of the VFD66 enclosure to the condensing unit control box, using knock outs provided. In conduit #2 insert shielded power cable supplied in accessory. Allow additional conduit length to remove the VFD Control enclosure from the top rail and place on side for servicing. 5. Connect power to condensor fan motors. Disconnect fan wires from fan contactor. Connect wires to field supplied wires in conduit # (See Figure 9). Connect field supplied wires in conduit # to VFD66 TB2 (See Figure 7). IMPORTANT: If the motor rotation is incorrect, interchange any two motor leads on TB2. Do not make changes to the input power supply wiring. 6. Connect power to VFD66 (See Figure 9). To avoid possible electric shock, wait at least 5 minutes after AC supply power has been disconnected from the VFD66 control before servicing the device. The VFD66 Condenser Fan Speed Control remains electrically charged for a period of time after power is removed. Failure to wait until the VFD66 control fully discharges could cause electric shock, personal injury, or death. Do not run low voltage cable in the same conduit or wiring troughs with high voltage wires. Running low and high voltage wires in the same conduit or wiring troughs may damage the equipment or cause system malfunction. 4. Cut two lengths of flexible conduit (Field Supplied) to connect from the VFD66 Control to the condensing unit control box. IMPORTANT: Wiring line-voltage input power to the wrong terminal block will damage the VFD66 control. Wire input power ONLY to Terminal Block (TB). Connect contactor terminal T to TB - L using the power harness BLK wire. Connect contactor terminal T2 to TB - L2 using the power harness RED wire. Connect contactor terminal T3 to TB - L3 using the power harness WHT wire. Connect bare wire of power harness to the grounding terminal on VFD66 control. 7. Ensure that the motor and VFD66 control are securely and adequetly grounded. Use ground connection terminals on the conduit entry bracket (See Figure 3). Use a spade terminal to connect to ground connection terminal. 4 Johnson Controls Unitary Products
POWER HARNESS M5 - L T M5-2 L2 T2 M5-3 L3 T3 BLK RED WHT VFD 66 TB TB2 L T L2 T2 L3 T3 FIELD SUPPLIED WIRING P 5 S 5 36 / BK T 2 37 / BR T2 3 38 / YEL T3 FM M GND GROUND TB3 2 3 4 GRN Pressure Transducer System (P 499) BLK 4 WHT RED 2 POWER HARNESS M7 - L T M7-2 L2 T2 M7-3 L3 T3 BLK RED WHT VFD 66 TB TB2 L T L2 T2 L3 T3 FIELD SUPPLIED WIRING P 7 S 7 2 3 54 / BK 55 / BR 56 / YEL T T2 T3 FM 3 M GND GROUND TB3 2 3 4 GRN Pressure Transducer System 2 (P 499) BLK 4 WHT RED 2 FIGURE 9-30, 40 & 50 TON LOW AMBIENT KIT WIRING DIAGRAM 8. Remove existing low ambient switch (LAS or LAS 2) (See Fig. ), located in the bottom ot the unit control box, and replace with new 0 F ambient switch (Item 9). Jumper Placement 9. Replace condenser fan motor fuses with new fuses (Item ). 20. Secure wiring in the unit control box in a neat workman like manner using wire ties. FIGURE 0 - JUMPER PLACEMENT ON PINS Check positioning of jumpers to assure proper operation of VFD66 control. Johnson Controls Unitary Products 5
To remove a jumper, reposition the jumper so that it is connected to only one pin on the jumper block. Keep the jumper because it may be needed in the future. To install a jumper, position the jumper on both pins. (See Figure 0). Jumper blocks (J2) and (J3) establish input modes. Jumpers (J2) and (J3) must be removed. Jumper block (J4) sets the motor acceleration/deacceleration time. Remove for 5 second period. Install for 30 second period. Jumper blocks (J5) and (J6) are preset at the factory and cannot be field adjusted. Jumper block (J7) determines the input signal type. Jumper (J7) must be installed. Jumper block (J8) establishes single or dual input signal operation. NOTE: The VFD66 is factory configured to accept single input operation; therefore, (J8) jumper should be installed on both pins for this application. Jumper block (J9) selects maximum output frequency of the control. Jumper (J9) must be installed for 60 Hz motors. VFD66 Operation A call for cooling closes the fan contactor powering the VFD66 control. As the discharge pressure rises above 340 PSIG during startup, the VFD66 control will increase the condenser fan speed accordingly. The unit s scroll compressor produces a rapid rise in discharge pressure upon startup and this, depending on the ambient temperature, will result in full speed operation of the condenser fan. After the discharge pressure has stabilized, the condenser fan speed may decrease especially when the ambient temperature is below 80 F. If the discharge pressure has stabilized and an additional compressor is energized, the condenser fan speed may increase, compensating for the rise in discharge pressure. As the discharge pressure falls below the 432 PSIG setpoint, the drive will reduce the condenser fan speed. As the ambient temperature drops below 40 F the condenser fan will slow to the minimum speed. The condenser fan will disengage when the discharge pressure drops below 295 PSIG. The system discharge pressure will increase when the condenser fan is disengaged causing the VFD66 control to increase the condenser fan speed. FIGURE - LAS-LOW AMBIENT SWITCH WIRING LOCATIONS 6 Johnson Controls Unitary Products
The VFD66 controls feature two diagnostic LEDs: POWER and ALARM. (See Figure 2.) The POWER LED illuminates when power is applied to the VFD66 controls. When power is disconnected from the VFD66 controls, this LED remains illuminated while the power supply capacitors discharge. If the motor is not running when power is removed, the LED may remain illuminated for up to 5 minutes, while the capacitors discharge. The ALARM LED indicates fault conditions and provides diagnostic information. Constant illumination of this LED indicates that the motor is overloaded and the VFD66 control shuts down the motor. When the ALARM LED flashes, the VFD66 control has shut down the motor. The number of times the ALARM LED flashes indicates the cause of the fault. (See Troubleshooting.) Output Voltage (VAC) 230 220 20 200 90 80 70 60 50 40 30 38 60 50 70 80 90 Input Voltage (VAC) 200 230 220 20 POWER LED (Green) ALARM LED (Red) 20 35 40 45 50 55 60 Output Frequency (Hz) FIGURE 3 - OUTPUT VOLTAGE AND FREQUENCY VS. INPUT POWER, 208/230 VAC FIGURE 2 - LED DISPLAY Trouble shooting Under Voltage Operation If the supply voltage drops below 60% of nominal, the VFD66 control stops the motor until the voltage returns to or rises above 60%. If the supply voltage is between 60% and 00% of nominal, the VFD66 control adjusts the output voltage and frequency to avoid damaging the motor. The VFD66 control adjusts the output frequency to match the available input power. (See Figure 3 and Figure 4.) Output Voltage (VAC) 460 440 420 460 440 420 400 400 380 380 360 360 340 340 320 320 Input 300 300 Voltage (VAC) 280 276 260 240 35 40 45 50 55 60 Output Frequency (Hz) FIGURE 4 - OUTPUT VOLTAGE AND FREQUENCY VS. INPUT POWER, 400/460 VAC Johnson Controls Unitary Products 7
TABLE 3: FAULT CONDITIONS Red Alarm LED Flashes Condition Definition Possible Cause Solution One Over Current Fault trips if output current momentarily exceeds approximately 200% of output current rating. Short in motor or leads VFD66 control is trying to accelerate load too quickly or load is too large. Check motor and wiring. Install jumper on J4 to slow acceleration/deceleration rate Two Over Voltage Fault trips if voltage exceeds 23% of nominal. Input voltage is too high. VFD66 control deceleration time is shorter than time needed to stop the load. Ensure that the input voltage matches the rating of the model of the VFD66 control. Install the jumper on J4 to slow acceleration/deceleration rate. Mechanical problems Inspect for mechanical problems. Three Motor Overload Trips if output current is 0% for minute. Excessive motor current Motor winding failure Four not used If overload is continuous, VFD66 control and motor with higher ratings may be required. Check motor specifications. Disconnect motor from VFD66 control. Ensure that resistance of each motor winding is within 5% of each other. If motor windings are defective, replace motor. Five Pulse Width Trips on detection of abnormal Modulation Generator microprocessor operation. Fault Internal fault Shut off power. Wait 5 minutes. Reapply power. If problem persists, replace VFD66 control. Six Logic Fault Internal circuitry fault Internal fault Shut off power. Wait 5 minutes. Reapply power. If problem persists, replace VFD66 control. Shutdown The ALARM LED indicates fault conditions and provides diagnostic information. Constant illumination of this LED indicates that the motor is overloaded and the VFD66 control shuts down the motor. When the ALARM LED flashes, the VFD66 control has shut down the motor. The number of times the ALARM LED flashes indicates the cause of the fault. See Table 3. After shutdown, there is a 30-second time delay before the VFD66 control initiates an automatic restart. The result is one of the following: If the fault condition is corrected, the VFD66 control continues to operate. After 500 seconds, the fault routine resets automatically. If the fault persists, the VFD66 controls lock out again, requiring reset. Resetting a Locked-Out VFD66 Control To reset a locked-out VFD66 control, follow the procedure below:. Disconnect power from the VFD66 control. 2. Wait 5 minutes to allow the internal capacitors to fully discharge. 3. Reapply power to the VFD66 control. Subject to change without notice. Printed in U.S.A. Copyright 200 by Johnson Controls, Inc. All rights reserved. 642546-UAI-A-080 Supersedes: Nothing Johnson Controls Unitary Products 5005 York Drive Norman, OK 73069