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ZX – Reliability Platform
Emerson Climate Technologies has designed the ZX platform
CDUs with extended operational capability in tough climatic
conditions. With our vast experience in the refrigeration industry,
ZX platform CDU is designed with a good protection scheme. ZX
protection scheme detect conditions that could cause damage
to the compressor, initiates a warning, temporary shutdown and
auto restarts. The control system will allow a complete shutdown
requiring manual restart only after several iterations of repeated warnings and temporary shutdowns are carried out. The control system
is driven by the built-in “E2 Controller”. Figure 02 shows the control strategy of the E2 Controller in a schematic form.
ZX – Performance Platform
Emerson Climate technologies with its leadership in scroll compression technology, apply the most advanced techniques to maximize
the possible operational efficiency at specific application envelopes. ZX MT CDU applies a patented suction-line injection technology.
Scroll compressor inherently operates at higher efficiency at MT application conditions. The suction-line injection provides a more
reliable MT operating envelope.
ZX MT CDU applies ZX series scroll compressor with liquid injection into the suction-line using an electronic expansion valve (EXV).
The EXV maintains an optimum feed of partially vaporized liquid refrigerant in the compressor suction to maintain a safe discharge gas
temperature. The controlled discharge gas temperature provides a more reliable solution for the MT envelope.
ZXL LT CDU applies vapor injection technology to achieve higher efficiency in LT refrigeration. Vapor injection allows an economizer
cycle to be applied on a scroll compressor thereby greatly enhancing compressor efficiency. This technology can be likened to 2- stage
compression with economizer cycle. Vapor injection improves efficiency by as much as 12% over a liquid injection system of the same
type. ZXL LT CDU applies ZXI series vapor injected compressor with vapor injection plate heat exchanger (PHE) to implement the vapor
injection technology.
ZX – Design Platform
The ZX platform CDUs are designed to provide the best operational
cost savings on a year around basis. Refrigeration equipment
operate continuously for7 days, 24 hours and 365 days. The ZX and
ZXI compressors, injection scheme and heat exchanger designs
are optimized to provide best efficiencies at annual averaged
temperature rather than at typical rating conditions. The typical
ambient on an annual basis follows a normal distribution pattern.
The highest and lowest ambient happens only for few hours as
shown in figure 01.
Hours
Low Ambient
High Ambient
Figure 01.
Shows Annual Typical Ambient Pattern
Real Time Monitoring
Of CDU Conditions
Warning Mode
Temporary Shutdown,
Signal, Auto Restart
Lock Out Mode
Alarm, Dialer Relay
Activation, Manual Restart
Figure 02.
Control Strategy of the E2 Controller
ZX Platform Condensing Unit was designed based on three factors
demanded by industry users:
Energy Efficiency
- Utilizing Copeland Scroll
®
compressor technology, variable speed fan motor, large capacity condenser coil
and advanced control algorithms, energy consumption is significantly reduced. End-users can save more than 20% on annual energy
costs rather than using hermetic reciprocating units.
Reliability
- Combining the proven reliability of Copeland Scroll
®
compressors with advanced electronics controller and
diagnostics, equipment reliability is greatly enhanced. Fault code alerts and fault code retrieval capabilities provide information to
help improve speed and accuracy of system diagnostics. Integrated electronics provide protection against over-current, over-heating,
incorrect phase rotation, compressor cycling, high pressure resets, low pressure cut-outs. It can also send out a warning message to
an operator when there is a liquid floodback, which can prevent critical damage on the unit.
Flexibility
- The slim shape and light weight make the ZX Condensing Unit aesthetically appealing and easy to install. The ultra
quiet variable-speed fan motor significantly reduces exterior sound levels, allowing additional location flexibility. Combined with wall
mounting capability, the ZX Condensing Unit delivers unmatched flexibility.
ZX Condensing Units are greatly suitable for walk-in cooler and freezer applications.
The advance scroll compressor technology, fan speed control and electronic controller are precisely collaborated in all units.
It also introduces variable-speed fan motors that go beyond national standards. Guaranteed dependable performance and
operation in food service applications while conveying higher energy efficiency and lower sound levels are the main objectives.
