KT-420-4 // PDF Download
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room / liquid temperature:
set point
suction pressure, suction gas temperature:
set point
on/off regulation
on/off regulation
stepped capacity regulation
stepped capacity regulation
regulation with FI
regulation with FI
time
time
Fig. 1: Capacity control with frequency inverter (FI) compared to on/off and stepped mechanical regulation
Refrigerating capacity as a function of the load is illustrated in the following graph. The frequency inverter has ad-
vantages especially in part-load.
0
20
40
60
80
100 %
COP /
r
EER
Fig. 2: Comparison of the control characteristics of reciprocating compressors of type 6JE with CR control vs. frequency inverter (FI): coefficient
of performance COP
r
/EER (ratio of refrigerating capacity to power absorbed) as a function of the load.
