Carel Heos - Page 50

50
ENG
Heos +0300078EN - rel. 1.6 - 23.11.2017
Alarm parameters and activation
AL (AH) is used to determine the activation threshold for the low (high)
temperature alarm LO (HI). The value set for AL (AH) is continuously
compared against the value measured by the probe defi ned by parameter
AA. Parameter Ad represents the alarm activation delay, in minutes; the
low temperature alarm (LO) is activated only if the temperature remains
below the value of AL for a time greater than Ad. The thresholds may
be relative or absolute, depending on the value of parameter A1. In the
former case (A1=0), the value of AL indicates the deviation from the set
point and thus the activation point for the low temperature alarm is: set
point - AL. If the set point changes, the activation point also changes
automatically. In the latter case (A1=1), the value of AL indicates the low
temperature alarm threshold. The low temperature alarm is signalled by
the buzzer and error code LO on the display. The same applies to the high
temperature alarm (HI), with AH instead of AL. I
The meaning of parameters AL2, AH2, Aa2 and A2 is similar to AL, AH, Aa,
A1, relative to the second set point.
Par Description Def UM Min Max
AH High temperature alarm threshold Al.1 10.0
(50.0)
°C
(°F)
-50.0
(-58.0)
50.0
(122.0)
10.0
(18.0)
°C
(°F)
0.0
(0.0)
50.0
(90.0)
AL Low temperature alarm threshold Al.1 4.0
(39.2)
°C
(°F)
-50.0
(-58.0)
50.0
(122.0)
°C
(°F)
0.0
(0.0)
50.0
(90.0)
A1 Type of alarm thresholds, relative to the
control set point or absolute
0: RELATIVE
1: ABSOLUTE
0--01
A0 Temperature alarm diff erential 2.0
(3.6)
°C
(°F)
0.1
(0.2)
20.0
(36.0)
Ad High and low temperature alarm delay 120 min 0 240
Ar Enable propagation of alarms from Slaves
to Master
0: NO; 1: YES
0--01
A7 Delay time for delayed external alarm 1 min 0 240
AH2 High temperature alarm threshold Al.2 10.0
(50.0)
°C
(°F)
-50.0
(-58.0)
50.0
(122.0)
10.0
(18.0)
°C
(°F)
0.0
(0.0)
50.0
(90.0)
AL2 Low temperature alarm threshold Al.2 4.0
(39.2)
°C
(°F)
-50.0
(-58.0)
50.0
(122.0)
°C
(°F)
0.0
(0.0)
50.0
(90.0)
A2 Type of alarm thresholds, relative to the
control set point or absolute
0: RELATIVE
1: ABSOLUTE
0--01
AdE Delayed external alarm delay priority
0: LOW (compressor not stopped)
1: HIGH (compressor stopped)
0--01
As Serial probe alarm delay 30 min 10 500
Tab. 8.b
Note:
• alarms LO(LO2) and HI(HI2) have automatic reset. A0 represents the
hysteresis between the alarm activation value and deactivation value.
A0A0
AL AH
HILO
Ux
ON
OFF
A0A0
AL2 AH2
HI2LO2
Ux
ON
OFF
Fig. 8.a
Key
LO, LO2 Low temperature alarms Ux Probes selected
HI, HI2 High temperature alarms