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MSEV Series and USHX Hardware Installation Manual Rev 1.7
1.4
About the MSEV Series and the USHX
The MSEV series valves Modular Silicon Expansion Valve (MSEV), High Capacity Modular Silicon
Expansion Valve (HC-MSEV) and the Very High Capacity Modular Silicon Expansion Valve (VHC-MSEV),
shown in Error! Reference source not found., are two-stage proportional control expansion valves that
utilize DunAn Microstaq’s patented silQflo® technology
.
The silQflo is a microelectromechanical systems
(MEMS) microvalve technology used to provide precise mass flow control for industry-standard HVAC and
refrigeration applications. The MSEV consists of a MEMS pilot valve which acts as a first stage valve that
applies varying fractions of fluid line pressure onto the second stage spool valve according to the
command signal provided by the Universal SuperHeat Controller (USHC). The MSEV is installed at the inlet
of the evaporator.
Figure 1-1 MSEV Family
The Universal SuperHeat Controller/Sensor (USHX), shown in Figure 1-2, is offered either as a:
a.
Universal SuperHeat Controller (USHC): To drive and control a MSEV series valve.
b.
Universal SuperHeat Sensor (USHS): To measure and report temperature, pressure, and
superheat values.
The USHX consists of an internal MEMS pressure sensor and a processing unit. It uses a wiring harness,
shown in Figure 1-3, to measure the evaporator temperature and control a MSEV series valve. The USHX
is installed at the outlet of the evaporator; it mounts on a ¼” access fitting and utilizes the Modbus RTU
communication protocol for user interaction.
Figure 1-2 USHX Wiring Harness
Figure 1-3 USHX
