Trane RTHD - Manual (Page 13)

13 RLC-PRC020-EN
Electrical Data Tables
Compressor motor electrical data is
provided in the data section for each
compressor size. Rated load amperes
(RLA), locked rotor wye amperes (LRA)
and expected inrush for the Wye-delta
and Solid State Starter configurations are
shown.
Although the terms “LRA” and “expected
inrush” are often used interchangeably,
the distinction applied here is that LRA is
the rated inrush for the motor, but
expected inrush is that allowed by the
starter, based on the specific
configuration.
Selecting starters in the Wye-delta or
Solid State configuration lowers
expected inrush vs. the Delta (or “across-
the-line”) configuration. A Solid State
Starter configuration lowers the
expected inrush by approximately 50
percent, while Wye-Delta lowers it by
approximately 66 percent.
The RLA is based on the motor’s
performance when reaching full rated
horsepower. The kW rating of the motor
will equal or exceed the kW requirement
indicated by the Series R computer
selection program at design conditions. If
motor kW draw at design conditions is
less than the kW rating of the motor, the
RLA at design conditions is determined
by multiplying the motor RLA (at the
desired voltage) by this ratio: design kW/
motor kW rating. This calculation is
performed within the Series R chiller
computer selection program, making
RLA available as part of the design
predictions. Predicted values include
power factor variation from point to point.
A voltage utilization range is tabulated for
each voltage listed. Series R chillers are
designed to operate satisfactorily over a
utilization range of ±10 percent of the
standard design voltages: (a) 200 V, 230 V,
380 V, 460 V, and 575 V for 60 Hertz, 3-
phase, and (b) 380 V, 400 V,
415 V for 50 Hertz, 3-phase.
Selection
Procedure
Unit Performance with Fluid Media
Other Than Water
Series R chillers can be provided with a
wide variety of fluid media other than
water, including ethylene glycol and
propylene glycol— in the evaporator,
condenser or both. Chillers using media
other than water are excluded from the
ARI 550/590-2003 Certification Program,
but are rated in accordance with ARI
Standard 550/590-2003. Trane factory
performance tests are only performed
with water as the cooling and heat-
rejection media. When considering
selection of media other than water,
contact the local Trane sales office for
chiller selections and factory
performance testing information.
Fluid media other than water lowers the
heat transfer coefficient, and therefore
reduces chiller performance. In general, it
is good practice to hold the percent glycol
added to within the minimum allowed by
the Trane selection program, based on
either (a) unit operating temperatures, or
(b) the operating temperatures the
evaporator or condenser water will
experience under its full range of
conditions. Adding more glycol than
required for the specific application is
equivalent to selecting a less efficient
chiller. Lower-viscosity glycols such as
ethylene will have less adverse impact
on chiller performance than higher-
viscosity glycols such as propylene.
Evaporator and Condenser Pressure
Drop
Pressure drop data is determined by the
Series R chiller computer selection
program available through local Trane
sales offices.
Dimensional Drawings
Dimensional drawings provided for
selection purposes illustrate overall
measurements of the unit. The
recommended service clearances are
those required to easily service the
Series R chiller.
All catalog dimensional drawings are
subject to change, and current submittal
drawings should be referenced for more
detailed dimensional information.
Dimensional drawings are also available
from the selection program. Contact the
local Trane sales office for submittal
information.