12-3
CONTROL SYSTEM
SM ALPHA 1-E.3 GB
12.3 General functions
12.3.1 COMP operation
For each Mode including POWER OFF & SB, a Min time delay of 3 min
before COMP restarting, excluding DEICING Mode
The Min operation time of COMP under different operating conditions is
Operation Mode
Min operation time of
COMP
Heat, Cool or Auto Modes 3 min.
Fan, Dry, Overfl ow, Protection modes, or mode change ignored
12.3.2 IFAN operation
• Min time interval between IFAN speed change in AUTOFAN Mode, is 30 sec.
• Min time interval between IFAN speed change in H/M/L Mode is 1 sec.
• IFAN speed in Heat/Cool Autofan Mode is determined according to the following table:
ΔT IFAN Speed
ΔT ≥ 2 HIGH
2 ≥ ΔT ≥ 1 MED
1 ≥ ΔT LOW
where in Heat Mode: ΔT = SPT-RT
in Cool Mode: ΔT = RT-SPT
Note:
• In Heat Mode, the rules in section 4.0.3 have the higher priority.
• The table above can be represent by a hysteresis curve which
will minimize the switching of the IFAN relay and will minimize the
change in IFAN speed:
T [
o
c]
L
M
H
IFAN speed
321
12.3.3 OFAN operation
• Min time interval between OFAN ON/OFF state change is 30 sec.
• In general, OFAN starts together with COMP.
12.3.4 HE operation
• Minimum Heaters ON or OFF time is 30 sec.
• Heaters can be activated only if IFAN is on.
To Next Page
Loading...
