EDM SYSCREW AIR EVO HSE

SYSCREW 380-1260 AIR EVO HSE
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Semi-hermetic screw compressors
The compressors installed in the units are semi-hermetic
screw type. The leading compressor is variable speed con-
trolled, integrating frequency inverter, sensors for protec-
tion and monitoring and solenoid valves (Vi control and
frequency inverter cooling) in a pre-wired package. The in-
verter driven compressor, in hybrid combination with a step
control type screw compressor, perform a continuous ca-
pacity control and offer precision in load management and
set-point regulation and enhanced seasonal performances.
Allcompressorsarettedwithanelectroniccontrolsystem
ensuringthefollowingfunctions:
Protection against high temperature and excessive load;
Correct direction of rotation;
Phase monitoring.
Besides the aforementioned functions, inverter driven
compressor is also equipped as standard of the following
additionalfeatures:
Frequency inverter cooling (solenoid valve, expansion
valve, regulator);
Low / High pressure transducer;
Oil level switch;
V
i
slidercontrolforefciencyoptimization.
Depending on unit size, step type compressors are supplied
with Part-Winding or Star-Delta starting system. Start-
Delta starting system is available as option for unit having
Part-Winding starting system as standard. Also soft starter
is available on request for step type compressors in order
to reduce the global value of inrush current.
Evaporator
Evaporator is of a new generation shell and tube, of pure
counterowtypeheatexchanger.Itisinsulatedwitha19
mmthickclosedcellpolyethylenefoammaterialandist-
ted with an electric heater on the external surface to pre-
vent the unit from freezing at a low temperature (down to
-18 °C) when the unit is off.
Water connections of heat exchanger are of Victaulic type
supplied with coupling stub pipe to be welded.
Condenser coils
The condenser coils are of microchannel type, made of
100%aluminium(ns,tubesandheaders)withtheexcep-
tion of pipe couplings which are in copper. Anti-corrosion
protection treatment is available as option.
Condenser fans
For each size, all versions keep the same number of fans.
Large diameter, direct drive axial type fans with electronic
brushless type motors are used in all available versions. A
dedicated version of electronic brushless type with more
powerful motor is used on HT and HPF versions, in order to
generatehigherairowrate(HT)oradditionalstaticpres-
sure up to 120 Pa (HPF).
Fansareequippedwithexternallymountednozzleprole
housing generating low sound levels.
Insuperlownoiseversions(S)anadditionalairdiffuseris
mounted on top of each fan motor to further reduce sound
power level without compromising unit performances.
Thanks to electronic brushless technology, fan speed con-
trol function is standard included for all the available rang-
es, allowing the units to operate in cooling mode at nega-
tive ambient temperatures.
Electrical board
The electrical board is located in a metal case arranged
outside the unit.The metal case has an IP54 protection
rating and is complete with grilles for natural air ventilation.
Electronic control
The units are supplied with the new microprocessor-based
electronic control and management system ensuring the
followingfunctions:
Managementoftheoperationofcompressors:
Power on/off
Anti-cycle management
Unloading for high pressure or high compressor pres-
sure ratio (integrated inside the curves of compressor
operating limits).
Chilled water temperature regulation (control option on
inletwatertemperatureRWT(P+Itype)oroutletwater
temperature LWT (neutral band type) of the evaporator.
Control of superheating on suction line.
Evaporator antifreeze protection.
Management of high and low pressure alarms.
Management of the compressors on the two circuits.
Management of the electronic expansion valves by
means of EEV controller.
Management of external interlocks.
Managementoftheremotecontrol:
Unit power on/off
Summary alarm signals
Remotesignalling,byfreecontacts:
Voltage presence.
Compressors in operation.
Circuit alarm unit.
Managementoftheonboardhydrokit(xed/variable
speed pumps).
Management of the heat recovery mode by means of
inlet water temperature sensor at the heat recovery con-
denser.
The unit controller can also clearly show all control param-
etersofthemachineontheliquidcrystaldisplay,suchas:
Display of superheating value.
Display of the temperature at the evaporator inlet and
outlet.
Display of the ambient air temperature.
Display of the circuit 1 and circuit 2 discharge pressure
and suction pressure.