Famco Danfoss Maneurop MT, Руководство пользователя

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16
SYSTEM DESIGN RECOMMENDATIONS
Discharge line
Filter driers
Operating limits
High Pressure
The pipe sizes selected for specifi c
systems may diff
er from these
recommended sizes.
It is recommended that the suction
lines are insulated to limit suction gas
superheat.
When the condenser is mounted
above the compressor, a loop above
the condenser and a U-trap close to the compressor are required to prevent
liquid draining from the condenser into
the discharge line during standstill.
For new installations with MPZ
compressors Danfoss recommends
using the Danfoss DML 100%-
molecular sieve, solid core fi lter drier.
Molecular sieve fi lter driers with loose
beads from third party suppliers shall
be avoided.
For servicing of existing installations
where acid formation is present the
Danfoss DCL solid core fi lter driers
containing activated alumina are
recommended.
The drier is to be oversized rather than
undersized. When selecting a drier,
always take into account its capacity
(water content capacity), the system
refrigerating capacity and the system
refrigerant charge.
A high pressure safety switch is
required to stop 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 in a
lockout circuit, or be a manual reset
device to prevent compressor cycling
around the high pressure limit. When a
discharge valve is used, the HP switch
must be connected to the service valve
gauge port, which cannot be isolated.
Low pressure
A low pressure safety switch is recommended to avoid compressor operation at
too low suction pressure.
Test pressure low side .................................... 25 bars(g)
Working pressure range high side ............ 13.2 - 27.7 bars(g)
Working pressure range low side .............. 1 - 7.2 bars(g)
Free internal volume at low side ................ 6.72 litres