Conductor Sizing for Typical Motors-Acromec

7/30/2019 Conductor Sizing for Typical Motors-Acromec

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Conductor Sizing For Typical Motor/Power Feeder ACROMEC - SNIFF SENSORY

Step 1: Initial Wire Size

1.1

Initial wire size is derived based on equipment

rating input, conductor load input, and wire type

selection

1.2 The cable is upsized by a safety factor of 1.25

1.3 Determine the wire size based on the NEC Table

Step 2: Adjustable Ampacity

Determine the Adjustable Wire Size Ampacity

2.1 Refer to the NEC table for this value

2.2 Determine the temperature rating of the conductor

2.

3

Since the Temperature Rating of the Conductor (input 2.3) does

not equal the Min. Equipment Terminal Rating (input 3.1), adjust

the wire size ampacity based on the Temperature Rating of the

Conductor

2.4 Initial Adjustable Wire Size Ampacity

Step 3: Ambient Temperature Adjustment : Determine the Ambient Temperature Adjustment

3.1 Determine the highest ambient temperature (input 3.3)

3.2

Based on the ambient temperature of 36-40 and the temp.

rating of 75, determine the temp. adjustment from the

correction factors table

Step 4: Bundle Adjustment : Determine the bundle adjustment factor

4.1 Determine the number of current-carrying conductors (input 3.5)

4.2Based on the current-carrying conductors of 1 - 3, determine the

adjustment factor based on the NEC Table

Step 5: Adjusted Ampacity: Determine the Adjusted Ampacity

5.1

Multiply the Adjustable Wire Size Ampacity (step

2.4) by the Temperature Adjustment (step 3.2) by

the Bundle Adjustment (step 4.2)

5.2 Multiply

5.3 Solve for Adjusted Ampacity

Step 6: Solve

6.1

Since Adjusted Amps is

greater than the Conductor

Load (input 1.2), Wire Size

stays the same

6.2 Final Wire Size

6.3 Final Conductor Load

Reference: Online Calculations : http://www.pumpcalcs.com/calculators/view/97/
http://www.pumpcalcs.com/calculators/view/97/http://www.pumpcalcs.com/calculators/view/97/http://www.pumpcalcs.com/calculators/view/97/


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Conductor Sizing For Typical Motor/Power Feeder ACROMEC SNIFF SENSORY (DX Reheat)

Step 1: Initial Wire Size

1.1

Initial wire size is derived based on equipment

rating input, conductor load input, and wire

type selection

1.2 The cable is upsized by a safety factor of 1.25

1.3

Determine the wire size based on the NEC

Table

Step 2: Adjustable Ampacity : Determine the Adjustable Wire Size Ampacity



2.

3

Since the Temperature Rating of the Conductor (input 2.3)

does not equal the Min. Equipment Terminal Rating (input

3.1), adjust the wire size ampacity based on the

Temperature Rating of the Conductor


Step 3: Ambient Temperature Adjustment

Determine the Ambient Temperature Adjustment

3.1 Determine the highest ambient temperature (input 3.3)

3.2

Based on the ambient temperature of 36-40 and the

temperature rating of 75, determine the temperature

adjustment from the correction factors table

Step 4: Bundle Adjustment

Determine the bundle adjustment factor

4.1 Determine the number of current-carrying conductors (input3.5)

4.2Based on the current-carrying conductors of 1 - 3, determine

the adjustment factor based on the NEC Table

Step 5: Adjusted Ampacity : Determine the Adjusted Ampacity

5.1

Multiply the Adjustable Wire Size Ampacity

(step 2.4) by the Temperature Adjustment

(step 3.2) by the Bundle Adjustment (step 4.2)

5.2 Multiply

5.3 Solve for Adjusted Ampacity

Step 6: Solve

6.1

Since Adjusted Amps is greater than the

Conductor Load (input 1.2), Wire Size stays the

same

6.2 Final Wire Size



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Nominal Size Breaker for Motor

1. This expert calculator provides the nominal and maximum size breaker for motor or feeder circuit given electrical load

requirements.

2. Although the expert calculator provides the maximum size breaker and overload protection allowed by code a smaller size

breaker or overload protection is generally used.

1. NEC Code Compliant

2. Motor /Feeder is less than 700 Amps

3. Motor / Feeder is less than 2000 Volts

1. NEC 2005 Sections 430 and 316

Legend

Step 1: Determine FLC : Determine FLC based on the first three inputs and the NEC tables

1.1 Determine Inputs

1.2 Determine FLC based on the inputs and the NEC tables

Step 2: Motor Branch Circuit - Conductor Size : Determine the motor branch circuit conductor size

2.1 Determine Inputs

2.2 Initial wire size is derived based on equipment rating input,

2.3 Determine Values

2.4 Determine the wire size based on the NEC table


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Step 3: Adjustable Ampacity : Determine the Adjustable Wire Size Ampacity



3.3 Since the Temperature Rating of the Conductor does not equal the Min.


Step 4: Ambient Temperature Adjustment : Determine the Ambient Temperature Adjustment

4.1 Determine the highest ambient temperature

4.2 Based on the ambient temperature of 36-40 and the temperature rating of 75,

Step 5: Bundle Adjustment

5.1 Determine the number of current-carrying conductors

5.2 Based on the current-carrying conductors of 1 - 3, determine the adjustment

Step 6: AA : Determine the Adjusted Ampacity

6.1 Multiply the Adjustable Wire Size Ampacity by the

6.2 Multiply

6.3 Solve for AA

Step 7: Solve

7.1 Since Adjusted Amps is greater than the

7.2 Final Wire Size


Step 8: Motor Overload Protection

8.1 Based on input 2.1


8.3 Since the service factor is greater than or equal to 1.15, the


8.5 Multiply

8.6 Solve


8.8 Multiply

8.9 Solve

Step 9 : Determine Max Motor Branch Circuit and Ground Fault Protection Device



9.3 Determine Value

9.4 Determine Nominal Size Breaker by multiplying

9.5 Multiply

9.6 Solve

9.7 Next larger size breaker may be used if motor

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Conductor Sizing for Typical Motors-Acromec