6 Optional functions
Optional functions
SMGB0091 rev.2 - 11/2015
108
Defrost control in current control demand mode (
F
)
This function allows to reduce the accumulated heating operation time and to force an earlier defrosting operation.
It is practical as a support of optional function "Fixing of current control demand function (
dE
)".
Setting of the fan performance curves (
F
)
This function allows to adjust the fan operation settings of RASC-(6/8/10)NPE units in order to achieve an optimal
performance of the fan unit. The correct static pressure setting (Low / Medium / High) has to be selected according to the
pressure values below:
• RASC-(4/5)HP: No setting is required.
• RASC-(6/8)HP: Select the “Medium pressure setting (
f:
)” for external static pressures higher than 50 Pa.
• RASC-10HP: Select the most suitable static pressure setting, depending on the installation conditions:
-
“Medium pressure setting (
f:
)”: For external static pressures between 50 and 80 Pa.
-
“High pressure setting (
f:
)”: For external static pressures higher than 80 Pa.
Default value: “Low pressure setting (
f:0
)”
In order to do so, measure the fan motor current and set the static pressure setting according to the following table: For
the measurement of the fan motor current, please refer to the following drawing:
Model
Fan motor current (A)
Medium pressure setting
(
f
:
0
)
High pressure setting
(
f
:
0
)
RASC-6HP
< 1.40 A
-
RASC-8HP
< 3.10 A
-
RASC-10HP
2.65 ~ 3.10 A
< 2.65
Compressor heater control mode (
F3
) (Only for RASC-(4-6)HNPE)
When the system is in stand-by mode, the crankcase heater is ON to ensure an optimum temperature of the
compressor's oil when the unit is required to start operation. This causes an additional heater input while the system is
not expected to start.
This function switches the crankcase heater OFF in stand-by mode; therefore saving energy while the unit is not running.
!
C A U T I O N
When starting up the system again, it remains in thermo-OFF mode until compressor oil is at an optimal temperature to start operation.
It is not recommended to use this control mode when immediate system starting is expected. The preparation time for the starting does
never exceed 4 hours.