A: There are many advantages and disadvantages to different types of fuel. Nearly all Generators use either gasoline, diesel, natural gas or propane. The following information will hopefully answer any questions or concerns you may have concerning different fuel sources.
Gasoline:
- Advantages:
- Common fuel source – easily obtained
- Increases portability of smaller generators
- Disadvantages:
- Highly flammable
- Short shelf life (approximately 12 months)
- Storing large quantities is hazardous
- May not be available during power outages
- Somewhat Expensive ($1.50 to $2.00 per Gallon)
- Inefficient
Propane:
- Advantages:
- Long shelf life
- Clean burning
- Easily stored in both large tanks or in smaller 5 – 10 gallon cylinders
- Obtainable during power outages – gas stations may be unable to pump fuel during an area wide outage
- Disadvantages:
- Pressurized cylinder of flammable gas
- Fuel system is more complicated (increased possibility of failure)
- Larger tanks are not aesthetically pleasing (unsightly)
- Fuel system plumbing results in higher installation cost
- Somewhat Expensive ($1.60 to $1.80 a gallon)
Natural Gas:
- Advantages:
- Unlimited fuel source – refueling not necessary
- Clean burning
- Available during power outages
- Disadvantages:
- May be unavailable during natural disasters (earthquakes, etc)
- Lower power output (30% less BTU’s per unit than gasoline)
- Fuel system plumbing results in higher installation cost
- Not available in many areas
Diesel:
- Advantages:
- Least flammable fuel source
- Easily obtained
- On site fuel delivery available
- Disadvantages:
- 18-24 month shelf life
- Installing large storage tanks raises cost of system
- May not be available during power outages
A: Power requirements must be determined to properly size your generator. We are providing some steps to assist you in approximating the size generator for your power needs. Please keep in mind that unless you are qualified, you should use a certified electrician to determine your power needs. At Triton Power it is our goal to assist our customers in any way possible. If you have any questions, please do not hesitate to contact us.
Steps to Determine Generator Requirements
- Determine your need. Do you want the generator to operate part or all of your home or office?
- Identify the appliances and/or tools the generator will need to power. The “Common Wattage Guide” below will help you determine your need.
- Determine the wattage for each appliance and tool you plan to use frequently.
- Identify motor and pump requirements. Use the motor and pump charts provided below.
- Calculate and total the wattage for the motors and pumps frequently used. Always use starting watts, not running watts, when determining the correct electrical load requirements.
- Total the wattage of the appliances & tools and the motors & pumps. Keep in mind that if you coordinate your power usage wisely you do not have to operate everything all at once. Therefore, for emergency use you don’t necessarily need to size the generator to operate everything simultaneously.
- Convert watts into kilowatts by dividing the watts in step VI. to determine the generator size required. Please note that it is suggested, although not absolutely necessary, to size the generator 20-25% over the size you determine your needs to be. This will allow room for future growth. For example, if you determine that you will need a 15 kW generator then it is advisable to purchase an 18 kW generator to accommodate future expansion.
Common Wattage Guide
Item | Running Watts | Starting Surge |
100 watt light bulb | 100 | 100 |
Radio AM/ FM stereo | 50-200 | 50-200 |
Radio CB | 50 | 50 |
Fan | 200 | 200 |
Television | 300-400 | 300-400 |
Microwave oven | 700 | 1000 |
Air conditioner | 3250 | 5000 |
Furnace fan (1/3 HP blower) | 600 | 1800 |
Vacuum cleaner | 600 | 750 |
Sump pump (1/3 HP) | 700 | 2100 |
Refrigerator/ Freezer | 800 | 2400 |
Freezer | 500 | 1500 |
6″ circular saw | 800 | 1000 |
Floodlight | 1000 | 1000 |
1/2″ electric drill | 1000 | 1250 |
Toaster | 1200 | 1200 |
Coffee maker | 1200 | 1200 |
Electric skillet | 1200 | 1200 |
14″ electric chain saw | 1200 | 1500 |
1/2 HP water well pump | 1000 | 3000 |
Hot plate | 1500 | 1500 |
Electric range | 10000 | 10000 |
10″ table saw | 2000 | 6000 |
Hot water heater | 5000 | 5000 |
Electric Motor Wattage Requirements
Electrical motors present special electrical startup considerations. They can require up to three times their rated running wattage to start. Motor nameplates generally will show starting watts, some as high as nine times the running wattage. Check the nameplate to be sure. Be certain to use the starting watts when figuring the correct electrical load requirements. Motor load requirements are listed below:
Motor Rating HP | Approximate Running Watts | Universal Motors Small Appliance | Reduction Induction Motors | Capacitor Motors |
1/8 | 275 | 400 | 600 | 850 |
1/4 | 400 | 500 | 850 | 1050 |
1/3 | 450 | 600 | 975 | 1350 |
1/2 | 600 | 750 | 1300 | 1800 |
3/4 | 850 | 1000 | 1900 | 2600 |
1 | 1000 | 1250 | 2300 | 3000 |
1 1/2 | 1600 | 1750 | 3200 | 4200 |
2 | 2000 | 2350 | 3900 | 5100 |
3 | 3000 | 3550 | 5200 | 6800 |
** Motors of higher HP are not generally used. |
Water Well Pump kW Requirements
Pump HP Rating | Externally Regulated Generator | Internally Regulated Generator | ||
� | Min. KW | Min. KVA | Min. KW | Min. KVA |
1/3 | 1.5 | 1.9 | 1.2 | 1.5 |
1/2 | 2.0 | 2.5 | 1.5 | 1.9 |
3/4 | 3.0 | 3.8 | 2.0 | 2.5 |
1 | 4.0 | 5.0 | 2.5 | 3.125 |
1 1/2 | 5.0 | 6.25 | 3.0 | 3.8 |
2 | 7.5 | 9.4 | 4.0 | 5.0 |
3 | 10.0 | 12.5 | 5.0 | 6.25 |
5 | 15.0 | 18.75 | 7.5 | 9.4 |
7 1/2 | 20.0 | 25.0 | 10.5 | 12.5 |
10 | 30.0 | 37.5 | 15.0 | 18.8 |
Notes:
- It is recommended that the generator be started before the pump motor is turned on.
- A majority of industrial generators are externally regulated. Generators must be sized to deliver at least 65% of the rated voltage during motor starting to ensure adequate motor starting torque.
- Industrial generators typically produce 300+ percent of rated capacity for 15-20 seconds during electrical surges.
- To convert KW into watts multiply KW (x) 1000.
A: Use the following conversion charts:
3 Phase Amperes – 80% Power Factor
KVA | KW | 208V | 220V | 240V | 380V | 416V | 440V | 480V |
6.3 | 5 | 17.5 | 16.5 | 15.2 | 9.6 | 8.6 | 8.3 | 7.6 |
9.4 | 7.5 | 26.1 | 24.7 | 22.6 | 14.3 | 13 | 12.3 | 11.3 |
12.5 | 10 | 34.7 | 33 | 30.1 | 19.2 | 17.3 | 16.6 | 15.1 |
18.7 | 15 | 52 | 49.5 | 45 | 28.8 | 26 | 24.9 | 22.5 |
25 | 20 | 69.5 | 66 | 60.2 | 38.4 | 34.7 | 33.2 | 30.1 |
31.3 | 25 | 87 | 82.5 | 75.5 | 48 | 43.4 | 41.5 | 37.8 |
37.5 | 30 | 104 | 99 | 90.3 | 57.6 | 52 | 49.8 | 45.2 |
45 | 36 | 125 | 118 | 108 | 68 | 62.5 | 59 | 54 |
56.3 | 45 | 156 | 147 | 135 | 85.5 | 78 | 74 | 68 |
62.5 | 50 | 173 | 165 | 152 | 96 | 86 | 83 | 76 |
75 | 60 | 208 | 198 | 181 | 115 | 104 | 99.6 | 91 |
93.8 | 75 | 261 | 247 | 226 | 143 | 130 | 123 | 113 |
100 | 80 | 278 | 264 | 240 | 154 | 139 | 133 | 120 |
125 | 100 | 347 | 330 | 301 | 192 | 173 | 166 | 150 |
156 | 125 | 433 | 413 | 375 | 240 | 217 | 208 | 188 |
187 | 150 | 520 | 495 | 450 | 288 | 260 | 249 | 225 |
219 | 175 | 608 | 577 | 527 | 335 | 304 | 289 | 264 |
250 | 200 | 694 | 660 | 601 | 384 | 347 | 332 | 301 |
312 | 250 | 866 | 825 | 751 | 480 | 434 | 415 | 376 |
375 | 300 | 1040 | 990 | 903 | 576 | 521 | 498 | 451 |
438 | 350 | 1220 | 1155 | 1053 | 672 | 607 | 581 | 527 |
500 | 400 | 1390 | 1320 | 1203 | 770 | 694 | 665 | 602 |
625 | 500 | 1735 | 1650 | 1504 | 960 | 868 | 830 | 752 |
750 | 600 | 2080 | 1970 | 1803 | 1141 | 1042 | 985 | 903 |
812 | 650 | 2257 | 2135 | 1958 | 1236 | 1129 | 1067 | 978 |
937 | 750 | 2605 | 2463 | 2257 | 1426 | 1303 | 1232 | 1128 |
Single Phase Amperes
KVA | 120\240 |
5 | 20.8 |
8 | 33.3 |
10 | 41.6 |
15 | 62.5 |
20 | 83.3 |
25 | 104 |
30 | 125 |
35 | 145 |
40 | 166 |
45 | 187 |
50 | 208 |
60 | 250 |
65 | 270 |
76 | 312 |
80 | 333 |
100 | 416 |
125 | 520 |
150 | 625 |
175 | 729 |
200 | 833 |
225 | 937 |
230 | 958 |
260 | 1041 |
275 | 1145 |
300 | 1250 |
350 | 1458 |
400 | 1666 |
425 | 1770 |
450 | 1876 |
500 | 2083 |
Nema Codes for Starting KVA/hp 3 Phase Motors*
CODE | STARTING KVA/HP | TYPICAL SIZE RANGE | CODE | STARTING KVA/HP | TYPICAL RANGE |
A | 0 – 3.15 | – | L | 9.0 -10.0 | 1 HP |
B | 3.15 – 3.55 | – | M | 10.0 – 11.2 | Less than 1 HP |
C | 3.55 – 4.0 | – | N | 11.2 – 12.5 | – |
D | 4.0 – 4.5 | – | P | 12.5 – 14.0 | – |
E | 4.5 – 5.0 | – | R | 14.0 – 16.0 | – |
F | 5.0 -5.6 | 15 HP and up | S | 16.0 – 18.0 | – |
G | 5.6 – 6.3 | 10 HP | T | 18.0 – 20.0 | – |
H | 6.3 – 7.1 | 7.5 and 5 HP | U | 20.0 – 22.4 | – |
J | 7.1 – 8.0 | 3 HP | V | 22.4 and up | – |
K | 8.0 – 9.0 | 2 and 1-1/2 |
A: There are many advantages and disadvantages to different types of fuel. Nearly all Generators use either gasoline, diesel, natural gas or propane. The following information will hopefully answer any questions or concerns you may have concerning different fuel sources.
Gasoline:
- Advantages:
- Common fuel source – easily obtained
- Increases portability of smaller generators
- Disadvantages:
- Highly flammable
- Short shelf life (approximately 12 months)
- Storing large quantities is hazardous
- May not be available during power outages
- Somewhat Expensive ($1.50 to $2.00 per Gallon)
- Inefficient
Propane:
- Advantages:
- Long shelf life
- Clean burning
- Easily stored in both large tanks or in smaller 5 – 10 gallon cylinders
- Obtainable during power outages – gas stations may be unable to pump fuel during an area wide outage
- Disadvantages:
- Pressurized cylinder of flammable gas
- Fuel system is more complicated (increased possibility of failure)
- Larger tanks are not aesthetically pleasing (unsightly)
- Fuel system plumbing results in higher installation cost
- Somewhat Expensive ($1.60 to $1.80 a gallon)
Natural Gas:
- Advantages:
- Unlimited fuel source – refueling not necessary
- Clean burning
- Available during power outages
- Disadvantages:
- May be unavailable during natural disasters (earthquakes, etc)
- Lower power output (30% less BTU’s per unit than gasoline)
- Fuel system plumbing results in higher installation cost
- Not available in many areas
Diesel:
- Advantages:
- Least flammable fuel source
- Easily obtained
- On site fuel delivery available
- Disadvantages:
- 18-24 month shelf life
- Installing large storage tanks raises cost of system
- May not be available during power outages
A: Power requirements must be determined to properly size your generator. We are providing some steps to assist you in approximating the size generator for your power needs. Please keep in mind that unless you are qualified, you should use a certified electrician to determine your power needs. At Triton Power it is our goal to assist our customers in any way possible. If you have any questions, please do not hesitate to contact us.
Steps to Determine Generator Requirements
- Determine your need. Do you want the generator to operate part or all of your home or office?
- Identify the appliances and/or tools the generator will need to power. The “Common Wattage Guide” below will help you determine your need.
- Determine the wattage for each appliance and tool you plan to use frequently.
- Identify motor and pump requirements. Use the motor and pump charts provided below.
- Calculate and total the wattage for the motors and pumps frequently used. Always use starting watts, not running watts, when determining the correct electrical load requirements.
- Total the wattage of the appliances & tools and the motors & pumps. Keep in mind that if you coordinate your power usage wisely you do not have to operate everything all at once. Therefore, for emergency use you don’t necessarily need to size the generator to operate everything simultaneously.
- Convert watts into kilowatts by dividing the watts in step VI. to determine the generator size required. Please note that it is suggested, although not absolutely necessary, to size the generator 20-25% over the size you determine your needs to be. This will allow room for future growth. For example, if you determine that you will need a 15 kW generator then it is advisable to purchase an 18 kW generator to accommodate future expansion.
Common Wattage Guide
Item | Running Watts | Starting Surge |
100 watt light bulb | 100 | 100 |
Radio AM/ FM stereo | 50-200 | 50-200 |
Radio CB | 50 | 50 |
Fan | 200 | 200 |
Television | 300-400 | 300-400 |
Microwave oven | 700 | 1000 |
Air conditioner | 3250 | 5000 |
Furnace fan (1/3 HP blower) | 600 | 1800 |
Vacuum cleaner | 600 | 750 |
Sump pump (1/3 HP) | 700 | 2100 |
Refrigerator/ Freezer | 800 | 2400 |
Freezer | 500 | 1500 |
6″ circular saw | 800 | 1000 |
Floodlight | 1000 | 1000 |
1/2″ electric drill | 1000 | 1250 |
Toaster | 1200 | 1200 |
Coffee maker | 1200 | 1200 |
Electric skillet | 1200 | 1200 |
14″ electric chain saw | 1200 | 1500 |
1/2 HP water well pump | 1000 | 3000 |
Hot plate | 1500 | 1500 |
Electric range | 10000 | 10000 |
10″ table saw | 2000 | 6000 |
Hot water heater | 5000 | 5000 |
Electric Motor Wattage Requirements
Electrical motors present special electrical startup considerations. They can require up to three times their rated running wattage to start. Motor nameplates generally will show starting watts, some as high as nine times the running wattage. Check the nameplate to be sure. Be certain to use the starting watts when figuring the correct electrical load requirements. Motor load requirements are listed below:
Motor Rating HP | Approximate Running Watts | Universal Motors Small Appliance | Reduction Induction Motors | Capacitor Motors |
1/8 | 275 | 400 | 600 | 850 |
1/4 | 400 | 500 | 850 | 1050 |
1/3 | 450 | 600 | 975 | 1350 |
1/2 | 600 | 750 | 1300 | 1800 |
3/4 | 850 | 1000 | 1900 | 2600 |
1 | 1000 | 1250 | 2300 | 3000 |
1 1/2 | 1600 | 1750 | 3200 | 4200 |
2 | 2000 | 2350 | 3900 | 5100 |
3 | 3000 | 3550 | 5200 | 6800 |
** Motors of higher HP are not generally used. |
Water Well Pump kW Requirements
Pump HP Rating | Externally Regulated Generator | Internally Regulated Generator | ||
� | Min. KW | Min. KVA | Min. KW | Min. KVA |
1/3 | 1.5 | 1.9 | 1.2 | 1.5 |
1/2 | 2.0 | 2.5 | 1.5 | 1.9 |
3/4 | 3.0 | 3.8 | 2.0 | 2.5 |
1 | 4.0 | 5.0 | 2.5 | 3.125 |
1 1/2 | 5.0 | 6.25 | 3.0 | 3.8 |
2 | 7.5 | 9.4 | 4.0 | 5.0 |
3 | 10.0 | 12.5 | 5.0 | 6.25 |
5 | 15.0 | 18.75 | 7.5 | 9.4 |
7 1/2 | 20.0 | 25.0 | 10.5 | 12.5 |
10 | 30.0 | 37.5 | 15.0 | 18.8 |
Notes:
- It is recommended that the generator be started before the pump motor is turned on.
- A majority of industrial generators are externally regulated. Generators must be sized to deliver at least 65% of the rated voltage during motor starting to ensure adequate motor starting torque.
- Industrial generators typically produce 300+ percent of rated capacity for 15-20 seconds during electrical surges.
- To convert KW into watts multiply KW (x) 1000.
3 Phase Amperes – 80% Power Factor
KVA |
KW |
208V |
220V |
240V |
380V |
416V |
440V |
480V |
6.3 |
5 |
17.5 |
16.5 |
15.2 |
9.6 |
8.6 |
8.3 |
7.6 |
9.4 |
7.5 |
26.1 |
24.7 |
22.6 |
14.3 |
13 |
12.3 |
11.3 |
12.5 |
10 |
34.7 |
33 |
30.1 |
19.2 |
17.3 |
16.6 |
15.1 |
18.7 |
15 |
52 |
49.5 |
45 |
28.8 |
26 |
24.9 |
22.5 |
25 |
20 |
69.5 |
66 |
60.2 |
38.4 |
34.7 |
33.2 |
30.1 |
31.3 |
25 |
87 |
82.5 |
75.5 |
48 |
43.4 |
41.5 |
37.8 |
37.5 |
30 |
104 |
99 |
90.3 |
57.6 |
52 |
49.8 |
45.2 |
45 |
36 |
125 |
118 |
108 |
68 |
62.5 |
59 |
54 |
56.3 |
45 |
156 |
147 |
135 |
85.5 |
78 |
74 |
68 |
62.5 |
50 |
173 |
165 |
152 |
96 |
86 |
83 |
76 |
75 |
60 |
208 |
198 |
181 |
115 |
104 |
99.6 |
91 |
93.8 |
75 |
261 |
247 |
226 |
143 |
130 |
123 |
113 |
100 |
80 |
278 |
264 |
240 |
154 |
139 |
133 |
120 |
125 |
100 |
347 |
330 |
301 |
192 |
173 |
166 |
150 |
156 |
125 |
433 |
413 |
375 |
240 |
217 |
208 |
188 |
187 |
150 |
520 |
495 |
450 |
288 |
260 |
249 |
225 |
219 |
175 |
608 |
577 |
527 |
335 |
304 |
289 |
264 |
250 |
200 |
694 |
660 |
601 |
384 |
347 |
332 |
301 |
312 |
250 |
866 |
825 |
751 |
480 |
434 |
415 |
376 |
375 |
300 |
1040 |
990 |
903 |
576 |
521 |
498 |
451 |
438 |
350 |
1220 |
1155 |
1053 |
672 |
607 |
581 |
527 |
500 |
400 |
1390 |
1320 |
1203 |
770 |
694 |
665 |
602 |
625 |
500 |
1735 |
1650 |
1504 |
960 |
868 |
830 |
752 |
750 |
600 |
2080 |
1970 |
1803 |
1141 |
1042 |
985 |
903 |
812 |
650 |
2257 |
2135 |
1958 |
1236 |
1129 |
1067 |
978 |
937 |
750 |
2605 |
2463 |
2257 |
1426 |
1303 |
1232 |
1128 |
Single Phase Amperes
KVA |
120\240 |
5 |
20.8 |
8 |
33.3 |
10 |
41.6 |
15 |
62.5 |
20 |
83.3 |
25 |
104 |
30 |
125 |
35 |
145 |
40 |
166 |
45 |
187 |
50 |
208 |
60 |
250 |
65 |
270 |
76 |
312 |
80 |
333 |
100 |
416 |
125 |
520 |
150 |
625 |
175 |
729 |
200 |
833 |
225 |
937 |
230 |
958 |
260 |
1041 |
275 |
1145 |
300 |
1250 |
350 |
1458 |
400 |
1666 |
425 |
1770 |
450 |
1876 |
500 |
2083 |
Nema Codes for Starting KVA/hp 3 Phase Motors*
CODE |
STARTING KVA/HP |
TYPICAL SIZE RANGE |
CODE |
STARTING KVA/HP |
TYPICAL RANGE |
A |
0 – 3.15 |
– |
L |
9.0 -10.0 |
1 HP |
B |
3.15 – 3.55 |
– |
M |
10.0 – 11.2 |
Less than 1 HP |
C |
3.55 – 4.0 |
– |
N |
11.2 – 12.5 |
– |
D |
4.0 – 4.5 |
– |
P |
12.5 – 14.0 |
– |
E |
4.5 – 5.0 |
– |
R |
14.0 – 16.0 |
– |
F |
5.0 -5.6 |
15 HP and up |
S |
16.0 – 18.0 |
– |
G |
5.6 – 6.3 |
10 HP |
T |
18.0 – 20.0 |
– |
H |
6.3 – 7.1 |
7.5 and 5 HP |
U |
20.0 – 22.4 |
– |
J |
7.1 – 8.0 |
3 HP |
V |
22.4 and up |
– |
K |
8.0 – 9.0 |
2 and 1-1/2 |
1
What type of fuel is best?
A: There are many advantages and disadvantages to different types of fuel. Nearly all Generators use either gasoline, diesel, natural gas or propane. The following information will hopefully answer any questions or concerns you may have concerning different fuel sources.
Gasoline:
- Advantages:
- Common fuel source - easily obtained
- Increases portability of smaller generators
- Disadvantages:
- Highly flammable
- Short shelf life (approximately 12 months)
- Storing large quantities is hazardous
- May not be available during power outages
- Somewhat Expensive ($1.50 to $2.00 per Gallon)
- Inefficient
Propane:
- Advantages:
- Long shelf life
- Clean burning
- Easily stored in both large tanks or in smaller 5 - 10 gallon cylinders
- Obtainable during power outages - gas stations may be unable to pump fuel during an area wide outage
- Disadvantages:
- Pressurized cylinder of flammable gas
- Fuel system is more complicated (increased possibility of failure)
- Larger tanks are not aesthetically pleasing (unsightly)
- Fuel system plumbing results in higher installation cost
- Somewhat Expensive ($1.60 to $1.80 a gallon)
Natural Gas:
- Advantages:
- Unlimited fuel source - refueling not necessary
- Clean burning
- Available during power outages
- Disadvantages:
- May be unavailable during natural disasters (earthquakes, etc)
- Lower power output (30% less BTU's per unit than gasoline)
- Fuel system plumbing results in higher installation cost
- Not available in many areas
Diesel:
- Advantages:
- Least flammable fuel source
- Easily obtained
- On site fuel delivery available
- Disadvantages:
- 18-24 month shelf life
- Installing large storage tanks raises cost of system
- May not be available during power outages
2
What size generator do I need?
A: Power requirements must be determined to properly size your generator. We are providing some steps to assist you in approximating the size generator for your power needs. Please keep in mind that unless you are qualified, you should use a certified electrician to determine your power needs. At Triton Power it is our goal to assist our customers in any way possible. If you have any questions, please do not hesitate to contact us.
Steps to Determine Generator Requirements
- Determine your need. Do you want the generator to operate part or all of your home or office?
- Identify the appliances and/or tools the generator will need to power. The "Common Wattage Guide" below will help you determine your need.
- Determine the wattage for each appliance and tool you plan to use frequently.
- Identify motor and pump requirements. Use the motor and pump charts provided below.
- Calculate and total the wattage for the motors and pumps frequently used. Always use starting watts, not running watts, when determining the correct electrical load requirements.
- Total the wattage of the appliances & tools and the motors & pumps. Keep in mind that if you coordinate your power usage wisely you do not have to operate everything all at once. Therefore, for emergency use you don’t necessarily need to size the generator to operate everything simultaneously.
- Convert watts into kilowatts by dividing the watts in step VI. to determine the generator size required. Please note that it is suggested, although not absolutely necessary, to size the generator 20-25% over the size you determine your needs to be. This will allow room for future growth. For example, if you determine that you will need a 15 kW generator then it is advisable to purchase an 18 kW generator to accommodate future expansion.
Common Wattage Guide
Item | Running Watts | Starting Surge |
100 watt light bulb | 100 | 100 |
Radio AM/ FM stereo | 50-200 | 50-200 |
Radio CB | 50 | 50 |
Fan | 200 | 200 |
Television | 300-400 | 300-400 |
Microwave oven | 700 | 1000 |
Air conditioner | 3250 | 5000 |
Furnace fan (1/3 HP blower) | 600 | 1800 |
Vacuum cleaner | 600 | 750 |
Sump pump (1/3 HP) | 700 | 2100 |
Refrigerator/ Freezer | 800 | 2400 |
Freezer | 500 | 1500 |
6" circular saw | 800 | 1000 |
Floodlight | 1000 | 1000 |
1/2" electric drill | 1000 | 1250 |
Toaster | 1200 | 1200 |
Coffee maker | 1200 | 1200 |
Electric skillet | 1200 | 1200 |
14" electric chain saw | 1200 | 1500 |
1/2 HP water well pump | 1000 | 3000 |
Hot plate | 1500 | 1500 |
Electric range | 10000 | 10000 |
10" table saw | 2000 | 6000 |
Hot water heater | 5000 | 5000 |
Electric Motor Wattage Requirements
Electrical motors present special electrical startup considerations. They can require up to three times their rated running wattage to start. Motor nameplates generally will show starting watts, some as high as nine times the running wattage. Check the nameplate to be sure. Be certain to use the starting watts when figuring the correct electrical load requirements. Motor load requirements are listed below:
Motor Rating HP | Approximate Running Watts | Universal Motors Small Appliance | Reduction Induction Motors | Capacitor Motors |
1/8 | 275 | 400 | 600 | 850 |
1/4 | 400 | 500 | 850 | 1050 |
1/3 | 450 | 600 | 975 | 1350 |
1/2 | 600 | 750 | 1300 | 1800 |
3/4 | 850 | 1000 | 1900 | 2600 |
1 | 1000 | 1250 | 2300 | 3000 |
1 1/2 | 1600 | 1750 | 3200 | 4200 |
2 | 2000 | 2350 | 3900 | 5100 |
3 | 3000 | 3550 | 5200 | 6800 |
** Motors of higher HP are not generally used. |
Water Well Pump kW Requirements
Pump HP Rating | Externally Regulated Generator | Internally Regulated Generator | ||
� | Min. KW | Min. KVA | Min. KW | Min. KVA |
1/3 | 1.5 | 1.9 | 1.2 | 1.5 |
1/2 | 2.0 | 2.5 | 1.5 | 1.9 |
3/4 | 3.0 | 3.8 | 2.0 | 2.5 |
1 | 4.0 | 5.0 | 2.5 | 3.125 |
1 1/2 | 5.0 | 6.25 | 3.0 | 3.8 |
2 | 7.5 | 9.4 | 4.0 | 5.0 |
3 | 10.0 | 12.5 | 5.0 | 6.25 |
5 | 15.0 | 18.75 | 7.5 | 9.4 |
7 1/2 | 20.0 | 25.0 | 10.5 | 12.5 |
10 | 30.0 | 37.5 | 15.0 | 18.8 |
Notes:
- It is recommended that the generator be started before the pump motor is turned on.
- A majority of industrial generators are externally regulated. Generators must be sized to deliver at least 65% of the rated voltage during motor starting to ensure adequate motor starting torque.
- Industrial generators typically produce 300+ percent of rated capacity for 15-20 seconds during electrical surges.
- To convert KW into watts multiply KW (x) 1000.
3
How do I convert AMPS to kW or KVA?
A: Use the following conversion charts:
3 Phase Amperes - 80% Power Factor
KVA | KW | 208V | 220V | 240V | 380V | 416V | 440V | 480V |
6.3 | 5 | 17.5 | 16.5 | 15.2 | 9.6 | 8.6 | 8.3 | 7.6 |
9.4 | 7.5 | 26.1 | 24.7 | 22.6 | 14.3 | 13 | 12.3 | 11.3 |
12.5 | 10 | 34.7 | 33 | 30.1 | 19.2 | 17.3 | 16.6 | 15.1 |
18.7 | 15 | 52 | 49.5 | 45 | 28.8 | 26 | 24.9 | 22.5 |
25 | 20 | 69.5 | 66 | 60.2 | 38.4 | 34.7 | 33.2 | 30.1 |
31.3 | 25 | 87 | 82.5 | 75.5 | 48 | 43.4 | 41.5 | 37.8 |
37.5 | 30 | 104 | 99 | 90.3 | 57.6 | 52 | 49.8 | 45.2 |
45 | 36 | 125 | 118 | 108 | 68 | 62.5 | 59 | 54 |
56.3 | 45 | 156 | 147 | 135 | 85.5 | 78 | 74 | 68 |
62.5 | 50 | 173 | 165 | 152 | 96 | 86 | 83 | 76 |
75 | 60 | 208 | 198 | 181 | 115 | 104 | 99.6 | 91 |
93.8 | 75 | 261 | 247 | 226 | 143 | 130 | 123 | 113 |
100 | 80 | 278 | 264 | 240 | 154 | 139 | 133 | 120 |
125 | 100 | 347 | 330 | 301 | 192 | 173 | 166 | 150 |
156 | 125 | 433 | 413 | 375 | 240 | 217 | 208 | 188 |
187 | 150 | 520 | 495 | 450 | 288 | 260 | 249 | 225 |
219 | 175 | 608 | 577 | 527 | 335 | 304 | 289 | 264 |
250 | 200 | 694 | 660 | 601 | 384 | 347 | 332 | 301 |
312 | 250 | 866 | 825 | 751 | 480 | 434 | 415 | 376 |
375 | 300 | 1040 | 990 | 903 | 576 | 521 | 498 | 451 |
438 | 350 | 1220 | 1155 | 1053 | 672 | 607 | 581 | 527 |
500 | 400 | 1390 | 1320 | 1203 | 770 | 694 | 665 | 602 |
625 | 500 | 1735 | 1650 | 1504 | 960 | 868 | 830 | 752 |
750 | 600 | 2080 | 1970 | 1803 | 1141 | 1042 | 985 | 903 |
812 | 650 | 2257 | 2135 | 1958 | 1236 | 1129 | 1067 | 978 |
937 | 750 | 2605 | 2463 | 2257 | 1426 | 1303 | 1232 | 1128 |
Single Phase Amperes
KVA | 120\240 |
5 | 20.8 |
8 | 33.3 |
10 | 41.6 |
15 | 62.5 |
20 | 83.3 |
25 | 104 |
30 | 125 |
35 | 145 |
40 | 166 |
45 | 187 |
50 | 208 |
60 | 250 |
65 | 270 |
76 | 312 |
80 | 333 |
100 | 416 |
125 | 520 |
150 | 625 |
175 | 729 |
200 | 833 |
225 | 937 |
230 | 958 |
260 | 1041 |
275 | 1145 |
300 | 1250 |
350 | 1458 |
400 | 1666 |
425 | 1770 |
450 | 1876 |
500 | 2083 |
Nema Codes for Starting KVA/hp 3 Phase Motors*
CODE | STARTING KVA/HP | TYPICAL SIZE RANGE | CODE | STARTING KVA/HP | TYPICAL RANGE |
A | 0 - 3.15 | - | L | 9.0 -10.0 | 1 HP |
B | 3.15 - 3.55 | - | M | 10.0 - 11.2 | Less than 1 HP |
C | 3.55 - 4.0 | - | N | 11.2 - 12.5 | - |
D | 4.0 - 4.5 | - | P | 12.5 - 14.0 | - |
E | 4.5 - 5.0 | - | R | 14.0 - 16.0 | - |
F | 5.0 -5.6 | 15 HP and up | S | 16.0 - 18.0 | - |
G | 5.6 - 6.3 | 10 HP | T | 18.0 - 20.0 | - |
H | 6.3 - 7.1 | 7.5 and 5 HP | U | 20.0 - 22.4 | - |
J | 7.1 - 8.0 | 3 HP | V | 22.4 and up | - |
K | 8.0 - 9.0 | 2 and 1-1/2 |