Trane SCIH manual electrical, Electrical Requirements, Electrical Data Calculations, Ground Wire

electrical

Installation requirements

WARNING

Ground Wire!

All field-installed wiring must be completed by qualified personnel. All field-installed wiring must comply with NEC and applicable local codes. Failure to follow this instruction could result in death or serious injury.

WARNING

Grounding Required!

Follow proper local and state electrical code on requirements for grounding. Failure to follow code could result in death or serious injury.

Electrical Requirements

Follow these guidelines, referring to unit wiring diagrams and supply power dimensional information to ensure correct electrical requirements at the installation site. Reference supply power wiring locations on unit submittals or in the “Dimensions andWeights” section. Specific unit wiring diagrams are provided on each unit. Use these diagrams for connections or trouble analysis.

WARNING

Hazardous voltage! Disconnect all electric power, including remote disconnects before servicing. Follow proper lockout/ tagout procedures to ensure the power can not be inadvertently energized. Failure to disconnect power before servicing could result in death or serious injury.

SXIH-SVX01B-EN

Supply PowerWiring

It is the installer’s responsibility to provide power supply wiring to the unit. Wiring should conform to NEC and all applicable code requirements.To ensure the unit supply power wiring is properly sized and installed, follow the guidelines below:

1.Verify the power supply available is compatible with the unit nameplate ratings.The supply power must be within 10% of the rated voltage listed on the unit nameplate.

2.Reference the electrical data inTable I- ED-1. Protect the electrical service from over current and short circuit conditions in accordance with NEC requirements. Size protection devices according to the electrical date on the unit nameplate.

3.If using a field-supplied disconnect, install it at or near the unit in accordance with NEC. Do not mount a field-supplied disconnect on the unit. Reference the electrical service entrance location on unit submittals.

4.Complete the unit power wiring connections onto either the main terminal block or the field-provided non-fused disconnect switch.

5.Provide proper unit grounding in accordance with local and national codes.

Electrical Data Calculations

RLA = Rated Load Amps

Compressor LRA = Locked Rotor Amps

Fan Motor LRA = Locked Rotor Amps,

N.E.C.Table 430 - 151

FLA = Full Load Amps, N.E.C.

Table 430 - 150

Voltage utilization range is ±10 percent

Determination of Minimum Circuit Ampacity (MCA)

MCA = 1.25 x largest motor amps (FLA or RLA) + the sum of the remaining motor amps.

Determination of Maximum Fuse Size (MFS)

MFS = 2.25 x largest motor amps (FLA or RLA) + the sum of the remaining motor amps.

If the rating value determined does not equal a standard current rating of over current protective device, use the next lower standard rating for the marked maximum rating.

WARNING

Live electrical components! During installation, testing, servicing and troubleshooting of this product, it may be necessary to work with live electrical components. Have a qualified licensed electrician or other individual who has been properly trained in handling live electrical components perform these tasks. Failure to follow all electrical safety precautions when exposed to live electrical components could result in death or serious injury.

Voltage Imbalance

Voltage imbalance on three-phase systems can cause motor overheating and premature failure. Maximum allowable imbalance is 2.0%, and the readings used to determine it must be measured at the compressor terminals.

Voltage imbalance is defined as 100 times the sum of the division of the three voltages from the average voltage. If, for example, the three measured voltages are 221, 230, 227, the average would be:

(221+230+227) = 226 volts 3

The percentage of voltage imbalance is then:

100*(226-221) = 2.2% 226

In this example, 2.2 percent imbalance of more than 2.0 percent exists, be sure to check the voltage at the unit disconnect and terminal block switch. If an imbalance at the unit disconnect switch does not exceed 2.0 percent, the imbalance is caused by faulty wiring within the unit. Be sure to conduct a thorough inspection of the unit electrical wiring connections to locate the fault, and make any repairs

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