Airwell ONG3-18, Service Manual

Page: 53 / 113

12-3
CONTROL SYSTEM
Revision 0 Service Manual - EDS
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
. n i m 3 s e d o M o t u A r o l o o C , t a e H
Fan, Dry
2YHUÀR
w, Protection modes, or mode change ignored
12.3.2 IFAN operation
x
Min time interval between IFAN speed change in AUTOFAN Mode, is 30 sec.
x
Min time interval between IFAN speed change in H/M/L Mode is 1 sec.
x IFAN speed in Heat/Cool Autofan Mode is determined according to the following table:
'
d e e p S N A F I T
' T t H G I H 2
2
t '
T
t
D E M 1
1
t '
W O L T
where in Heat Mode:
'
T = SPT-RT
in Cool Mode:
'
T = RT-SPT
Note:
x
In Heat Mode, the rules in section 4.0.3 have the higher priority.
x
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
3 2 1
12.3.3 OFAN operation
x
Min time interval between OFAN ON/OFF state change is 30 sec.
x
In general, OFAN starts together with COMP.
12.3.4 HE operation
x Minimum Heaters ON or OFF time is 30 sec.
x Heaters can be activated only if IFAN is on.