Specifications

113
CURRENT UNBALANCE (Maximum 10%)
Voltage unbalance will cause a current unbalance, but a
current unbalance does not necessarily mean that a
voltage unbalance exists. A loose terminal connection or
a build-up of dirt or carbon on one set of contacts (using
the example of L1 as the problem leg) would cause a
higher resistance on that leg (L1) than on L2 and L3. The
current follows the path of least resistance, so the current
increases in legs L2 and L3. Higher current causes more
heat to be generated in the motor windings.
Percent (%) of current unbalance is calculated in the
same way as voltage unbalance (see the previous
section), with a maximum acceptable current unbalance
of 10%.
5.0 COMPRESSOR SERVICE WORKSHEETS
Carlyle recommends that the Compressor Service
Worksheets (pages 114 and 115) be copied (and enlarged, if
preferred) and filled out for each compressor at initial start-
up and each time the compressor is serviced. Comparing the
data from current worksheets to past records will allow the
service technician to diagnose system changes and prevent
compressor failures. This information is also very useful in
preventing a repeat failure.