TM 9-6150-226-13
Table 2-2.
RULE OF THUMB FORMULAS
RESISTIVE LOADS
INDUCTIVE LOADS
(LIGHT OR HEAT)
(MOTORS)
K W = QTY X WATTS
1000
KW = QTY X HP
I
= QTY X WATTS
VOLTS
I = QTY X AMPS
NOTE:
Use above formulas
NOTE:
Use above formulas
when watts and volts are
when horsepower and amps
given.
are given.
When volts and amps are known use (volts x amps) to find watts. P = E x I
NOTE
RULE OF THUMB
INDUCTIVE LOADS ONLY
1 H P =
1KW
3/4 HP = .750KW
1/2 HP = .500KW
1/4 HP = .250KW
1/8 HP = .125KW
(1) When using the rule of thumb formulas the following points
apply:
(a) Total load (KW) will determine the size of generator set
needed.
(b) Total Amps (I) will determine the proper DISE or PDISE
feeder and/or distribution systems, the proper output connectors(s), and will
be used for correct phase balancing.
(c) Quantity (QTY) is the number of like items.
(d) Voltage (Volts):
When the generator output voltage is set
at 120/208 volts AC, 120 volts is single-phase (1) and 208 volts is three-phase
(3).
Single phase requires at least a two wire connection (one hot lead and
one neutral lead).
Three-phase requires at
hot leads and one neutral lead).
NOTE
DISE and PDISE can only be used
120/208 volts AC, all other
different type of generator set.
least a four wire connection (three
with generators rated at
ratings will
require a
2-29
