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8. power required to start motor, 9. how much power can generator supply – Hobart Welding Products CONTRACTOR 3225D User Manual

Page 44

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OM-480 Page 40

10-8. Power Required To Start Motor

S-0624

1

Motor Start Code

2

Running Amperage

3

Motor HP

4

Motor Voltage

To find starting amperage:

Step 1: Find code and use table to
find kVA/HP. If code is not listed,
multiply running amperage by six to
find starting amperage.

Step 2: Find Motor HP and Volts.

Step 3: Determine starting amper-
age (see example).

Welding generator amperage out-
put must be at least twice the
motor’s running amperage.

VOLTS

AMPS

HP

230

2.5

1/4

Hz

PHASE

CODE

60

1

M

AC MOTOR

1

2

3

4

Single-Phase Induction Motor Starting Requirements

Motor Start

Code

G

H

J

K

L

M

N

P

KVA/HP

6.3

7.1

8.0

9.0

10.0

11.2

12.5

14.0

EXAMPLE: Calculate the starting amperage required for a 230 V, 1/4
HP motor with a motor start code of M.

Starting the motor requires 12.2 amperes.

11.2 x 1/4 x 1000

230

= 12.2 A

kVA/HP x HP x 1000

VOLTS

= STARTING AMPERAGE

Volts = 230 HP = 1/4 Using Table, Code M results in kVA/HP = 11.2

10-9. How Much Power Can Generator Supply?

Ref. ST-800 396-A / S-0625

1

Limit Load To 90% Of
Generator Output

Always start non-resistive (motor)
loads in order from largest to small-
est, and add resistive loads last.

2

5 Second Rule

If motor does not start within 5
seconds, turn off power to prevent
motor damage. Motor requires
more power than generator can
supply.

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