CGAD-SVN02C-EN 31
Correction
Excessive unbalance between the
phases of a three-phase system will
cause the motors to overheat and to
breakdown. The maximum unbalance
allowed is of 2%. Unbalance of voltage
can be defined as 100 times the
maximum deviation of the three
voltages (three phases) subtracted
from the arithmetic average (without
taking into consideration the signal)
divided by the arithmetic average.
Example:
If the three voltages measured on a
line are 221 volts, 230 volts, and 227
volts, the arithmetic average would be:
(221 + 230 + 227)/3 = 226 V
The percentage of unbalance is then:
100 x (226 - 221)/226 = 2.2%
The result indicates that there is an
unbalance that is greater than that
permitted of 0.2%. This unbalance
between phases may result in an
unbalance of current of 20%, and the
result would be an increase in the
temperature of the motor's coiling and
a lowering of the motor's durability.
Electrical
Data
WARNING!!
Turn off the electrical energy and wait for
rotation to cease on allthe equipment
beforedoing services,inspecting,
ortesting the units.
To Next Page
Loading...