Standby Electric Generators for Alaskan Residences Advice & Installation
452-1151 • 1-800-770-GVEA • www.gvea.com Use of this publication is not a substitute for the use of sound judgement by the user. This booklet is intended to provide a useful summary of information, not to provide complete advice suitable for all situations. This booklet is not a substitute for the most current provisions of the National Electric Code or for the judgement of a licensed electrician.
Life in Alaska is exciting and different. No small part of the spice of life here is the environment: the scenic beauty, the weather, the scale of the natural forces. Introduction Floods, earthquakes, severe storms and wildfires are also part of living in Alaska. Natural disasters create potential emergency situations and power outages can occur. Even if these events are uncommon, they do happen with some regularity in nearly all regions of Alaska.
Sizing a Generator for Your Needs Generators are rated not only by their voltage, but also by their power output, measured in watts or kilowatts – one kilowatt equals 1000 watts. Some generators may also be rated in volt-amperes or kilovolt-amperes, which are related to watts but are not the same. You can approximate the power output in watts by multiplying the volt-ampere rating by 0.8. The kilowatt, or watt rating is given on the generator nameplate and can also be listed in the owners manual.
. Check your calculations with your local utility or generator dealer before you purchase a generator. As most portable generators are rated in watts or Kw, assume your total load in volt-amperes (from Step 4) equals the total load in watts (i.e. 5000 VA = 5000 watts) It is important to note a generator should be purchased with circuit breaker overcurrent protection.
service, a 100-amp two-pole transfer switch will be required. If the transfer switch only transfers an emergency panel served from a 60-amp breaker, a 60-amp two-pole transfer switch will be required. If the transfer switch is for a 20-amp 120-volt branch circuit, then only a 20-amp single-pole transfer switch will be required. The transfer switch must also be rated for the available fault current.
Plug Flexible Cord Type SJEW-A Maximum Generator Size [-50oC (-58oF) to 105oC (221oF)] (in volt-amperes VA, watts @ .8 pf) 5-20R 3/12 2400 VA, 1920 W L5-20R 3/12 2400 VA, 1920 W L5-30R 3/10 3600 VA, 2880 W L14-20R 4/12 4800 VA, 3840 W L14-30R 4/10 7200 VA, 5760 W ignates outdoor rated cable. The first number is the number of conductors, and the second number is the wire size in American Wire Gauge (AWG). For example, the 3/12 designates three conductors of #12 AWG size.
Range 3 generators may be designed as mobile units or for permanent mounting. All generators should be mounted per the manufacturer’s recommendations. Permanently mounted generators can be mounted on a reinforced concrete base at least 6 inches (15 cm) thick. Anchor bolts can be used to attach the generator to the concrete pad. If the standby unit is permanently installed indoors, be sure the ventilation is adequate. Air inlets and outlets should each be open at least half a square-foot (0.
will not increase the electric power output, and it can cause problems with your motors and other frequency sensitive equipment, such as clocks. 8. Put the transfer switch in the generator position. 9. Connect the electric load. Start the largest motor first, adding other loads when each successive motor reaches its full operating speed. Do not add the loads too quickly. If the generator stops, repeat steps 2, 5, 6, 7 and 8. 10. Check the voltage often to make sure you are not overloading the generator.
8 Figure 1: 120/240 Volt Standby Electrical Generator Supplying Total Load
Figure 2: 120/240 Volt Standby Electrical Generator Supplying Critical Load 9
10 Figure 3: 120 Volt Standby Electrical Generator Supplying Single Branch Circuit
Figure 4: 120 Volt Standby Electrical Generator Supplying Multiple Branch Circuits 11
12 Figure 5: 120/240 Volt Standby Electric Generator Supplying Multiple Branch Circuits
Kind of Equipment Horsepower (Hp) Running Watts (W) Essential Lighting Refrigerator 1/4 - 1/2 Freezer 1/4 - 1/2 Furnace, stoker 1/4 Furnace, oil burner 1/6 Furnace, hot water circ pump 1/6 - 1/4 Furnace, blower 1/4 - 1/2 Hot water heater - electric Portable electric heater Microwave oven Car headbolt heater Well pump Water pump 1/2 - 2 800 - 2500 Optional Toaster Mixer Coffeemaker Electric iron Electric range Electric clothes dryer - blower 1/6 Electric clothes dryer - heater W
