Simplex, Inc., 5300 Rising Moon Road, Spring
fi
eld, IL 62711-6228 • 217-483-1600 • Fax 217-483-1616
Lbdman8p.indd (04/11) • © 2011 Simplex, Inc. All Rights Reserved. • Printed in the USA. • www.simplexdirect.com
LOAD BANK MANUAL • LBD Series • page 12 of 16
APPENDIX B -
C A L C U L A T I O N S
& FORMULAS
The following calculations are used to
determine the actual kilowatt load being
applied by the Load Bank, when line
voltages and currents are known (at
1.0 power factor).
3 Ph a s e
1. Read all three line currents and
fi
nd
the average reading.
2. Read all three line-to-line voltages
and
fi
nd the average reading.
3. Multiply the average current times
the average voltage.
4. Multiply the answer of step #3 times
the square root of 3 (1.732).
5. Divide the answer of step #4 by 1000.
The answer is the actual kilowatts of
load being applied by the Load Bank.
S i n g l e P h a s e
1. Determine the line current.
2. Determine the line-to-line voltage.
3. Multiply the line current times the
line-to-line voltage.
4. Divide the answer of step #3 by 1000.
5. The answer of step #4 is the actual
kilowatts being applied by the load
bank.
EXAMPLES
Using line voltages and currents:
3 Phase
Current Readings
Voltage Readings
A
1
= 249A
V
1-2
= 481V
A
2
= 250A
V
2-3
= 479V
A
3
= 254A
V
3-1
= 483V
Average Current =
A
1
+ A
2
+ A
3
3
=
2
4 9 + 2 5 0 + 2 5 4
3
=
251A
Average Voltage =
V
1-2
+ V
2-3
+ V
3-1
3
=
4
8 1 + 4 7 9 + 4 8 3
3
=
481V
Kilowatts = V
o l t s x Amps x 1 . 7 3 2
1000
=
4
8 1 x 2 5 1 x 1 . 7 3 2
1000
= 209.1KW
Single Phase
Current Reading: 150A
Voltage Reading: 240V
Kilowatts =
V
o l t s x Amps
1000
=
150
x 240
1000
= 36.1KW
