12-8. Power Required To Start Motor
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| AC MOTOR |
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| VOLTS | 230 | AMPS | 2.5 | ||
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| CODE | M | Hz | 60 |
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| HP | 1/4 | PHASE 1 |
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Single-Phase Induction Motor Starting Requirements
Motor Start | G |
| H | J | K | L | M |
| N |
| P |
Code |
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KVA/HP | 6.3 |
| 7.1 | 8.0 | 9.0 | 10.0 | 11.2 |
| 12.5 |
| 14.0 |
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kVA/HP x HP x 1000 = STARTING AMPERAGE |
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EXAMPLE: Calculate the starting amperage required for a 230 V, 1/4 |
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HP motor with a motor start code of M. |
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Volts = 230 | HP = 1/4 Using Table, Code M results in kVA/HP = 11.2 | ||||||||||
11.2 x 1/4 x 1000 | = 12.2 A | Starting the motor requires 12.2 amperes. | |||||||||
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1Motor Start Code
2Running Amperage
3Motor HP
4Motor 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.
12-9. How Much Power Can Generator Supply?
1
2
1Limit Load To 90% Of Generator Output
Always start
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.
Ref.