Carrier 50VQP084-300 specifications Field Power Supply Wiring

•Boiler drains and other valves should be connected using a “T” connector to allow acid flushing for the heat exchanger.

•Do not overtighten connections.

•Route piping to avoid service access areas to unit.

•Use PVC SCH80 or copper piping material.

NOTE: PVC SCH40 should not be used due to system high pressure and temperature extremes.

Water Supply and Quantity — Check water supply. Water supply should be plentiful and of good quality. See Table 2 for water quality guidelines.

IMPORTANT: Failure to comply with the above required water quality and quantity limitations and the closed- system application design requirements may cause damage to the tube-in-tube heat exchanger that is not the responsi- bility of the manufacturer.

In all applications, the quality of the water circulated through the heat exchanger must fall within the ranges listed in the Water Quality Guidelines table. Consult a local water treat- ment firm, independent testing facility, or local water authority for specific recommendations to maintain water quality within the published limits.

Step 8 — Field Power Supply Wiring

WARNING

To avoid possible injury or death due to electrical shock, open the power supply disconnect switch and secure it in an open position during installation.

CAUTION

Use only copper conductors for field-installed electrical wiring. Unit terminals are not designed to accept other types of conductors.

All field-installed wiring, including the electrical ground, MUST comply with the National Electrical Code (NEC) as well as applicable local codes. In addition, all field wiring must conform to the Class II temperature limitations described in the NEC.

Refer to unit wiring diagrams Fig. 27-30 for a schematic of the field connections which must be made by the installing (or electrical) contractor. See Tables 3 and 4 for fuses sizes.

Consult the unit wiring diagram located on the inside of the compressor access panel to ensure proper electrical hookup. The installing (or electrical) contractor must make the field connections when using field-supplied disconnect.

Operating voltage must be the same voltage and phase as shown in electrical data shown in Tables 3 and 4.

Make all final electrical connections with a length of flexi- ble conduit to minimize vibration and sound transmission to the building.

POWER CONNECTION — Line voltage connection is made by connecting the incoming line voltage wires to the L side of the CC terminal. See Tables 3 and 4 for correct wire and maximum overcurrent protection sizing.

SUPPLY VOLTAGE — Operating voltage to unit must be within voltage range indicated on unit nameplate.

On 3-phase units, voltages under load between phases must be balanced within 2%. Use the following formula to deter- mine the percentage voltage imbalance:

% Voltage Imbalance

= 100 x	max voltage deviation from average voltage
	average voltage
Example: Supply voltage is 420-3-50.
	AB = 425 volts
	BC = 422 volts
	AC = 417 volts
	Average Voltage =	425 + 422 + 417
		3
	=	1264
		3

= 421

Determine maximum deviation from average voltage:

(AB) 425 – 421 = 4 v (BC) 422 – 421 = 1 v (AC) 421 – 418 = 3 v

Maximum deviation is 4 v. Determine percent voltage imbalance.

% Voltage Imbalance = 100 x 4214

= 0.95%

This amount of phase imbalance is satisfactory as it is below the maximum allowable 2%.

Operation on improper line voltage or excessive phase imbalance constitutes abuse and may cause damage to electri- cal components.

NOTE: If more than 2% voltage imbalance is present, contact local electric utility.

420-VOLT OPERATION — All 380/420 volt units are factory wired for 380 volts. The transformers may be switched to 420-volt operation (as illustrated on the wiring diagram) by disconnecting the VIO lead at L1 and attaching the BRN lead to L1. Close open end of VIO lead.

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