Assessments - 2, GPA: 4.5
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No. 1 No. 2 OFM POWER SUPPLY DISCONNECT SIZE V---Ph--Hz Min Max RLA LRA RLA LRA Qty FLA (ea) MCA FUSE or HACR BRKR FLA LRA D*16 Z*16 208/230-- 3-- 60 187 253 25.0 164 25.0 164 3 1.5 65.6/65.6 90/90 68/68 342/342 460---3---60 414 506 12.2 100 12.2 100 3 0.8 32.1 40 33 208 575---3---60 518 633 9.0 78 9.0 78 3 0.7 24.1 30 25 164 D*25 Z*25 208/230-- 3-- 60 187 253 30.1 225 30.1 225 4 1.5 78.5/78.5 100/100 82/82 467/467 460---3---60 414 506 16.7 114 16.7 114 4 0.8 43 50 45 238 575---3---60 518 633 12.2 80 12.2 80 4 0.7 32 40 33 170 Legend and Notes for Table 10 LEGEND: BRKR - --- Circuit breaker CO - --- Convenient outlet FLA --Full Load Amps LRA - --- Locked Rotor Amps MCA - --- Minimum Circuit Amps Protection NEC - --- National Electrical Code PWRD CO - --- Powered convenient outlet RLA - --- Rated Load Amps UNPWR CO - --- Unpowered convenient outlet NOTES: 1. In compliance with NEC requirements for multimotor and combination load equipment (refer to NEC Articles 430 and 440), the overcurrent protective device for the unit shall be fuse or HACR breaker. Canadian units may be fuse or circuit breaker. 2. The MCA values are calculated in accordance with The NEC. Article 440. 3. Motor RLA and LRA values are established in accordance with Underwriters’ Laboratories (UL). Standard 1995. 4. The 575---v units are UL, Canada---listed only. 5. Unbalanced 3-Phase Supply Voltage Never operate a motor where a phase imbalance in supply voltage is greater than 2%. Use the following formula to determine the percentage of voltage imbalance. Example: Supply voltage is 230-3-60 max voltage deviation from average voltage % Voltage Imbalance = 100 x average voltage AB = 224 v BC = 231 v AC = 226 v (224 + 231 + 226) 681 Average Voltage = = 33 = 227 Determine maximum deviation from average voltage. (AB) 227 – 224 = 3 v (BC) 231 – 227 = 4 v (AC) 227 – 226 = 1 v Maximum deviation is 4 v. Determine percent of voltage imbalance. 4 % Voltage Imbalance = 100 x 227 = 1.76% This amount of phase imbalance is satisfactory as it is below the maximum allowable 2%. IMPORTANT: If the supply voltage phase imbalance is more than 2%, contact your local electric utility company immediately. 22 PRE-START-UP IMPORTANT: Before beginning Pre-Start-Up or Start-Up, review Start-Up Checklist at the back of this book. The Checklist assures proper start-up of a unit and provides a record of unit condition, application requirements, system information, and operation at initial start-up. CAUTION! UNIT DAMAGE HAZARD Failure to follow this caution may result in equipment damage. Do not attempt to start the condensing unit, even momentarily, until the following steps have been completed. Compressor damage may result. System Check 1. The electrical power source must agree with the unit’s nameplate rating. 2. Check all air handler(s) and other equipment auxiliary components. Consult the manufacturer’s instructions regarding any other equipment connected to the condensing unit. If the unit has field-installed accessories, be sure all are properly installed and correctly wired. If used, the airflow switch must be properly installed. 3. Check tightness of all electrical connections. 4. Be sure liquid line and low side of the system are properly leak checked and dehydrated. 5. Be sure the unit is properly charged. See “Preliminary Charge”, below. 6. Open the liquid line and suction line service valves. 7. The crankcase heater must be firmly attached to the compressor crankcase. Be sure the crankcase is warm (heater must be on for 24 hours before starting compressor). Turn On Crankcase Heater — Turn on the crankcase heater for 24 hours before starting the unit to be sure all the refrigerant is out of the oil.To energize the crankcase heater, proceed as follows: 1. Set the space thermostat set point above the space temperature so there is no demand for cooling. 2. Close the field disconnect. Preliminary Charge — Before starting the unit, charge liquid refrigerant into the high side of the system through the liquid service valve. The amount of refrigerant added must be at least 80% of the operating charge listed in the Physical Data table (Tables 1A through 2B, pages 6 through 9). Allow high and low side pressures to equalize before starting compressor. If pressures do not equalize readily, charge vapor on low side of system to assure charge in the evaporator. Refer to GTAC II, Module 5, Charging, Recover, Recycling, and Reclamation for liquid charging procedures. CAUTION! UNIT DAMAGE HAZARD Failure to follow this caution may result in equipment damage. Prior to starting compressor, a preliminary charge of refrigerant must be added to avoid possible compressor damage. START-UP 38AU Units: The compressor crankcase heater must be on for 24 hours before start-up. After the heater has been on for 24 hours, the unit can be started. If no time elapsed since the preliminary charge step was completed, it is unnecessary to wait the 24-hour period. Preliminary Checks 1. Check that e...