Sub-Zero CRC-2020, User Manual

Page: 6 / 18

10
Sr.
No.
Parameter setting method
Description of parameters and functions.
Parameter
01
P2
Parameter Function : To set allowable high
temperature limit.
To change P2 parameter,
press the set key. Use UP/DOWN key to set desired value.
Once set at a particular value, this will not
allow the set point to go above this
value and below P3 setting.
Example : Setting this parameter
0
at 50.0 C will not allow the set point to go
0
above 50.0 C also if the temperature
0
reaches 50.0 C, the display will show HT
(High Temperature). The alarm will be
ON. But at power on till the AL delay is
over controller will not generate HT Alarm.
SP+0.5ºC 50.0ºC 50.0ºC
Range
Min Max Fact. Set
(Message on Display)
09
Sr.
No.
Parameter setting method
Description of parameters and functions.
Parameter
02
P3
Parameter Function : To set allowable low
temperature limit.
Use UP/DOWN key to set desired value.
Once set at a particular value, this will not
allow the set point to go below this value
and above P2 setting.
Example : Setting this parameter at
0
-50.0 C will not allow the set point to go
0
below -50.0 C also if the temperature
0
reaches -50.0 C, the display will show LT
(Low Temperature). The alarm will be ON.
To change parameter,
press the set key.
P3
-50.0ºC SP-0.5ºC -50.0ºC
Range
Min Max
Fact. Set
(Message on Display)
Use UP/DOWN keys to set desired value.
Example(Cooling Mode) : If the set point
0
is set at 10.0 C and differential is set at
0
2.0 C, then when the system reaches
0
10.0 C, the comp. relay will cutout. Since
0
the differential is 2.0 C, the comp. Relay
0
will cutin at 12.0 C
0 0
(10.0 C + 2.0 C).
03
P4
Parameter Function : To set the differential for
compressor restart.
To change
P4
press the set key.
parameter,
0.5ºC 20.0ºC 2.0ºC
Range
Min Max Fact. Set
P5
Parameter
Use UP/DOWN keys to set desired value.
In time it may be possible that the display
may be offset by a degree or so.
To compensate for this error, you may
need to add or minus the degrees
required to achieve the correct
temperature.
Example : The temperature on the
O
display is 28.0 C, whereas the actual
O
temperature is 30.0 C. You will need to set
O
this parameter to 2.0 C, which means that
once out of the programming parameter,
the display will show the temperature
O O O
30.0 C (28.0 C + 2.0 C).
To change P5
press the set key. parameter,
04
Function : To set probe calibration.
-10.0ºC 10.0ºC 0.0ºC
Range
Min Max Fact. Set
HT
LT
Use UP/DOWN keys to set desired value.
This parameter is used to protect the fan
from restarting in a short period of time
and can be set between 0 to 20 minutes.
Example : If this parameter is set at 3
minutes, the compressor will cut off at
the set temperature, but will not restart
for a minimum of 3 minutes, even if the
differential is achieved earlier. This
P6
Parameter
To change P6
press the set key. parameter,
05
Function : To set time delay between
relay restart time.
1 Min 20 Min 3 Min
Range
Min Max Fact. Set
CRC-2020 CRC-2020