GEA Grasso V Series - General Limits of Operation

Besides this practical instrument Grasso is able to make, in advance, an
analyses based on a theoretical profile of the compressor and the running
conditions. In this way an indication of the running costs ( Total Costs of
Ownership, TCO) can be produced.
4.2 GENERAL LIMITS OF OPERATION GRASSO V
When operating the compressor, none of the limits of operation as stated in the
table below must be exceeded. *
13
The diagrams overleaf represent the overall fields of application in which the
individual operation limits are taken into account.
General limits and fields of operation
REFRIGERANT
NH
3
Compressor speed n
Grasso V
300(T) .. 600(T)
min.
500 min
-1
for direct drive
600 min
-1
for V-belt drive
Grasso V
700(T) ..
1800(T)
500 min
-1
for direct drive
700 min
-1
for V-belt drive
Grasso V
300(T) .. 600(T)
max.
1500 min
-1
Grasso V
700(T) ..
1800(T)
1200 min
-1
Suction pressure = evaporating
pressure =crankcase pressure
p
o
/t
o
Grasso V min.
0.3 bar(a)
-55 °C
Grasso V
300(T) .. 600(T)
max.
8.5 bar(a)
19 °C
Grasso V
700(T) ..
1800(T)
7.0 bar(a)
13 °C
Suction superheat
delta-t
Grasso V
min. >0 °C
Superheat LP suction Grasso VT
Actual suction temperature
t
a
Grasso V(T) min. -50 °C
Discharge pressure =
condensing pressure
tc = saturated condensing
temperature *
14
*
15
P
s
*
16
/
t
c
Grasso V
300(T) .. 600(T)
max.
26.0 bar(a)
60 °C
Discharge pressure =
condensing pressure *
17
*
18
Grasso V
700(T) ..
1800(T)
24.0 bar(a)
56 °C
13 In practice, it is not so much the individual operation limits as combinations of them that are
decisive for the conditions under which a compressor may operate. To check the various
possibilities in this respect, use should be made of the "fields of application" ).
14 This pressure is also the maximum allowable pre-set value of the HP safety switch.
15 CAUTION!: When adjusting the HP and/or LP safety switch, care should be taken that the pressure
difference Δp=(p
C
-p
o
) never exceeds 26.0 bar(g).
16 “Ps“ is mentioned on type plate of the compressor
17 This pressure is also the maximum allowable pre-set value of the HP safety switch.
18 CAUTION!: When adjusting the HP and/or LP safety switch, care should be taken that the pressure
difference Δp=(p
C
-p
o
) never exceeds 19.0 bar (g).
APPENDIX; Product Information (PI)
GENERAL LIMITS OF OPERATION GRASSO V
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