TM 9-6150-228-13&P
2.4.4.1 Determine the user's needs. Consult with each user and make a careful record of the electrical requirements of
his electrical equipment (120/208 Vac, 50/60 Hz only) as follows:
NOTE
Voltage (E), amperage (I), and wattage (P) are mathematically calculated as follows:
(1 -phase)
(3-phase)
P = E x I
P = 1.73 x E x I
E = P
E = P
I
1.73xI
P
P
I=E
I =1.73 x E
2.4.4.1.1 Record the voltage rating (120 V/1-ph or 208 VJ3-ph).
2.4.4.1.2 Record the amperage rating.
2.4.4.1.3 Record the wattage rating.
2.4.4.1.4 Record the number of receptacles (outlets) required.
2.4.4.1.5 Draw up a table of these values as illustrated in Table 2-2.
2.4.4.1.6 Add up the total! watt load (9640 watts for the example). Change this value to kilowatts (divide by 1000) (9.6
kW for the example).
2.4.4.1.7 Select power generation equipment with enough capacity to support this load.
2.4.4.1.8 Cable Selection Choice of power output cables should be based on amperage requirements and distances
between locations selected for the generator set(s), the power distribution panel, DISE equipment, and the shelters, vans,
and tents. Remember, the longer the cable the greater the voltage loss at the user's end. Keep total! cable lengths
between generator set and user equipment under 250 feet (76.20 m). If the user equipment is sensitive to voltage loss,
shorter cables may have to be used.
High voltage is present in this equipment during operation. Do not submerge cable
connectors in water. Failure to observe this warning could result in serious injury or
death.
CAUTION
Bury cables which cross roadways. Power cables can be damaged by tactical vehicles.
2.4.5
Cable Routing. Route the system cables to avoid vechile roadways and troop walkways. If a cable must cross
a roadway, bury the cable to protect it from damage, refer to FM 20-31. Do not lay cable connectors in depressions
where water can collect.
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