Motor Supply; Compressor Ambient Temperature; Application Envelope - Danfoss MLM Series Application Manuallines

A G
PPLICATION UIDELINES

Motor supply

Compressor ambient
temperature
High ambient temperature
Low ambient temperature

Application envelope

65
60
Transient conditions
55
50
45
40
35
30
25
20
15
10
5
-35 -30
O
PERATING CONDITIONS
MLZ / MLM scroll compressors can be operated
at nominal voltages as indicated in table section
"Motor voltage". Under-voltage and over-voltage
operation is allowed within the indicated voltage
MLZ / MLM compressors can be applied from
-35°C to 50°C ambient temperature. The compres-
sors are designed as 100 % suction gas cooled
In case of enclosed fi tting and high ambient tem-
perature it's recommend to check the tempera-
ture of power wires and conformity to their insu-
lation specifi cation.
Although the compressor itself can withstand low
ambient temperature, the system may require
specifi c design features to ensure safe and reli-
The operating envelopes for MLZ/MLM scroll
compressors are given in the fi gures below,
where the condensing and evaporating tempera-
tures represent the range for steady-state opera-
tion. Under transient conditions, such as start-up
and defrost, the compressor may operate outside
this envelope for short periods.
The fi gures below show the operating envelopes
for MLZ compressors with refrigerants R404A/507,
MLZ - R404A / R507
RGT: 18°C
-25 -20 -15
Evaporating temperature (°C)
FRCC.PC.015.A4.02
ranges. In case of risk of under-voltage operation,
special attention must be paid to current draw
and start assist for single-phase compressors may
be required.
without need for additional fan cooling. Ambient
temperature has very little eff ect on the compres-
sor performance.
In case of safe tripping by the internal compres-
sor overload protection the compressor must
cool down to about 60°C before the overload will
reset. A high ambient temperature can strongly
delay this cool-down process.
able operation. See section 'Specifi c application
recommendations'.
R134a and R22. The operating limits serve to de-
fi ne the envelope within which reliable opera-
tions of the compressor are guaranteed:
• Maximum discharge gas temperature: +135°C
• A suction superheat below 5 K is not recom-
mended due to the risk of liquid fl ood back
• Minimum and maximum evaporating and con-
densing temperatures as per the operating
envelopes.
-10 -5 0 5 10 15
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