# How do you size a circuit breaker for a motor

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You must size the conductors at 125% of the motor FLC [430.22(A)]. You must size the overloads no more than 115% to 125% of the motor nameplate current rating, depending on the conditions [430.32(A)(1)]. You must size the short-circuit ground-fault protection device from 150% to 300% of the motor FLC [Table 430.52].

## What size breaker do I need for a 2 hp motor?

How to Calculate How What Size Circuit Breaker a Machine will Need:

HorsePower of Main Motor 220 Volts, 1 phase 220 Volts, 3 phase
1 Hp 5.6 Amps 2.8
2 11.2 5.6
3 16.8 8.4
4 22.4 11.2

## What size breaker do I need for a 100 hp motor?

Electrical motor wiring data – NEMA amps, starter size, HMCP size for motors ranging 1/2 to 500 hp

Motor HP NEMA amps Motor Circuit Protector type HMCP (ampere)
50 65 100
60 77 150
75 96 150
100 125 200
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## What size breaker do I need for a 30 amp motor?

A 20 amp breaker is all you’d ever need for a 220v 3HP motor.

## What size breaker do I need for a 7.5 hp motor?

Re: Wire and breaker size for 7.5 hp motor

You need 50 amp rated wire with a 50-100 amp breaker.

## What size breaker do I need for a 5 hp motor?

In fact code recommends a 60 amp circuit breaker for a 5 hp 230v motor, but with overload protection.

## What size breaker do I need for a 20 amp motor?

Full Load Current: Three Phase AC Motors

Motor Horsepower Size Breaker
10 230V 460V 50 30
15 230V 460V 70 40
20 230V 460V 100 50
25 230V 460V 100 50

## What size wire do I need for a 1 hp motor?

Motors are hot to touch. Provide ample circulation around motor. For example: 1-1⁄2 Hp motor at 115 volts over a distance of 150 feet, use #8 wire. Inrush is the amp consumption of a motor during start-up.

## What gauge wire do I need for 200 feet?

Generally speaking, you will need 1 AWG copper or 2/0 aluminum conductors for this to work. This should be large enough wiring to safely carry those 100 amperes. It will also maintain the power quality over larger distances.

## How many amps is a 50 hp motor?

HP 200 Volts 380-415 Volts
40 120 66
50 150 83
60 177 103
75 221 128

## How do I size a motor overload?

The overloads are determined using 125% of the FLA, 7A x 1.25 = 8.75A. The maximum allowable size for the overloads is 9.8A. The overloads can be sized at 140% of the FLA if the overloads trip at rated load or will not allow the motor to start, 7A x 1.4 = 9.8A.

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## What size breaker do I need for a 220?

In the below diagram you will notice that for a 220-volt outlet you would need a two-pole breaker. What this means is that the breaker will take the power from the panel by the two very different phases. Each one is 110 volts. Combined you have your 220 volts.

## How many amps does a 1.5 hp motor draw?

Common Horsepower to Amps Conversions

Horsepower Amps Voltage
1.5 HP 10.4 A 120 V
1.75 HP 12.1 A 120 V
2 HP 13.8 A 120 V
2.5 HP 17.3 A 120 V

## How many amps does a 7.5 hp motor draw?

How many amps does a 7.5 hp motor draw?

HP 200 Volts 440-480 Volts
2 7.8 3.4
3 11 4.8
5 17.5 7.6
7.5 25.3 11

## What size wire do I need for a 3 HP motor?

Three Phase (230 Volt) – Wire Size Selection Guide*
HP Cable Length
3 14 14
5 14 14
7 1/2 14 12

## How do you measure a 3 phase circuit breaker?

For AC loads, you must also divide by the appropriate phase factor. For 3-phase loads, you divide the VA by the nominal voltage and by the square root of three (approximately 1.732). If your total 3-phase load in a 480V system is 50,000VA, what size breaker do you need? 50,000VA ÷ (480V × 1.732) = 60.2A.