Danfoss PSH019, Инструкции по применению

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Operating conditions
Continuous operations beyond the compressor’s
operating envelope will cause serious damage
to the compressor. In this case, an additional
discharge gas temperature protection device is
required for compressor protection.
The discharge gas temperature protection device
must be attached to the discharge line within
150mm from the compressor discharge port and
must be thermally insulated and tightly fixed on
the discharge pipe.
The protection setting value should be 135°C, to
shut down the compressor when the measured
temperature reach this value.
Discharge temperature
protection
The operating envelope for PSH scroll
compressors is given in the figure below, where
the condensing and evaporating temperatures
represent the range for steady-state operation.
The operating limits serve to define the
envelope within which reliable operations of the
compressor are guaranteed:
• Maximum discharge gas temperature: +135°C • A suction superheat below 5 K is not allowed
due to the risk of liquid flood back,
• Maximum suction superheat of 20K
• A subcooling below 4K is not recommended to
ensure proper liquid injection,
• Minimum and maximum evaporating and
condensing temperatures as per the operating
envelopes.
Application envelope
10
20
30
40
50
60
70
Co
nd
en
si
ng
te
m
pe
ra
tu
re
(°
C)
Heating
SH5K
-35 -30 -20 -10 0 10 20 -25 -15 -5 5 15 25
Evaporating temperature (°C)
High and low pressure
protection
A high pressure (HP) safety switch is required to
shut down the compressor should the discharge
pressure exceed the values shown in the table
below. The high pressure switch can be set to
lower values depending on the application and
ambient conditions. The HP switch must either be placed in a lockout circuit or consist of a manual
reset device to prevent cycling around the high-
pressure limit. If a discharge valve is used, the HP
switch must be connected to the service valve
gauge port, which must not be isolated. High pressure
18
FRCC.PC.022.A4.02
Application Guidelines