Application guidelines
33
FRCC.PC.014.A4.22
Operating conditions
Short cycle control is directly provided by the
CDS302 frequency converter, when parameter
28.0* is enabled.
The function is factory set to enabled, with
minimum running time 12 seconds and interval
between starts 300 seconds.
Short cycle settings are accessible in parameter
28.0* list, in the “compressor functions” menu.
Short cycle timer function
Discharge gas
temperature protection
function
A discharge temperature monitor function can be
enabled in the frequency converter. All settings
are available in parameter list 28.2*, they are
factory preset as follow:
• 28.20: [0] none - temperature source (sensor
input)
• 28.21: [60] °C - temperature unit
• 28.24: 130 - warning level
• 28.25: [1] decrease cooling - warning action
• 28.26: 145 - emergency level
• 28.27: is the actual discharge temperature
measured by the sensor.
To activate the discharge temperature moni-
tor function, with the factory setting, the only
modification required is to connect the sensor to
Analog Input 54 (4.20 mA) between 13 and 54,
and set the parameter 28.20 to “[2] Analog input
54”. When the warning level is reached “decrease
cooling” action starts by decreasing the com-
pressor speed by steps of 600 rpm (10 Hz) every
3 minutes until the temperature, either drops
below the level, programmed in parameter 28.24
(warning level) or exceed the level programmed
in parameter 28.26 (emergency level). When the
emergency level is reached, the compressor is
stopped and the frequency converter shows an
“alarm”.
Application envelope
59
68
77
86
95
104
113
122
131
140
149
158
167
-22
-13 -4 5 14 23 32 41 50 59 68
Evaporating temperature °F
C
ondensing
te
m
pera
ture
°F
30 - 90 Hz
50 - 90 Hz
50 - 90 H
z
Superheat: 11°F
