how do we select a copper power cable for a 10 HP, 1440 rpm, 440V, 3 phase AC m

how do we select a copper power cable for a 10 HP, 1440 rpm,
440V, 3 phase AC motor?

Question Posted / mm

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how do we select a copper power cable for a 10 HP, 1440 rpm, 440V, 3 phase AC motor?..

Answer / yoyoma

These are the steps required to detemining the cable size
required for your motor.

1) Determine the FLA (full load amps) or FLC (full load
current) of the motor. This can be obtained from the
motor nameplate or datasheet. If these are not avaiable
refer to the charts in the NEC or CSA code books.

2) As per NEC and CSA the cable is to be sized a minimum of
an additional 25% of the rated FLA or FLC (FLAx1.25)

3) Next a derating factor may need to be applied for both
temperature and grouping of cable in a raceway or cable
tray. These should be found in your code books. Multiply
these factors to your answer from number 2 above.

4) Once you have done 1 through 3, you should have a
current value larger than that of the rated FLA or FLC
of the motor. Use this current value to select the cable
size that can handle this current.

5) Lastly, as a verification you must also determine if the
cable size selected in number 4 above is sized so that
the voltage drop is no less than 3% (some go as high as
5%) of the source voltage (in your case 4400V x 0.97 =
426.8V). If your cable is undersized then you must
continue to increase the size until the voltage drop is
within 3%.

6) Once these are all done, your cable will be sized
correctly and accounting for all additional factors.

Is This Answer Correct ?

3 Yes

0 No

how do we select a copper power cable for a 10 HP, 1440 rpm, 440V, 3 phase AC motor?..

Answer / wareagle

1. Determine the amperage for the 10 hp motor. You can do
this by looking at the NEC chart at this site.
http://www.electricmotorshop.net/index.php?
option=com_content&view=article&id=687&Itemid=352
2.From this chart the 10 HP requires 14 amps. You then go
to a wiring table and select the conductor that has an
ampacity of 14 amps or more. The local code will dictate
your selection.
3.This wire choice does not include voltage drop
requirements.You may need a large size to reduce voltage if
necessary.
4. local codes may dictate other requirements.

Is This Answer Correct ?

5 Yes

3 No

how do we select a copper power cable for a 10 HP, 1440 rpm, 440V, 3 phase AC motor?..

Answer / r k choudhary

first we have to find out the ampere then as per cable
sizing chart select the cable but one thing always kept in
mind that for safe working (losses ,voltage drop,efficiency
of motor) consider somthing extra size of cable.

Is This Answer Correct ?

1 Yes

1 No

how do we select a copper power cable for a 10 HP, 1440 rpm, 440V, 3 phase AC motor?..

Answer / sudhakar

depending on the current rating of the motor only we will
choose the cable rating and consider the current density of
the copper also important

Is This Answer Correct ?

2 Yes

3 No

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