Configuration of 3
rd
probe as 2nd evap-
orator probe
The 3
a
probe can be used to control the
defrosting of a second evaporator by con-
figuring a relay output as a 2nd evaporator
defrost relay (see par. H21…H26).
To implement this function:
a) configure the 3
rd
probe in 2nd evapora-
tor defrost control mode (par. H43=2EP).
b) configure a relay output as 2nd evapo-
rator defrost relay (configuration parame-
ters H21…H26).
c) define the defrost mode by setting
parameter H45.
Start of defrosting
If two evaporators are used, defrosting
starts in three different ways that are
determined by parameter H45.
• H45=0: Defrosting is enabled by con-
trolling that the temperature of the 1st
evaporator is lower than parameter dSt,
•H45=1: Defrosting is enabled by control-
ling that at least one of the two probes is
below its end of defrosting temperature
(dSt for the 1st evaporator and dS2 for
the 2nd evaporator)
• H45=2: Defrosting is enabled by control-
ling that both the probes are below their
respective end of defrosting set points
(dSt for the 1st evaporator and dS2 for
the 2nd evaporator).
The probe error condition is considered
the defrost calling probe.
When defrosting is terminated by a probe
or is timed out (see par. dEt), dripping fol-
lows (see par. dt).
End of defrosting
If two evaporators are used, defrosting
ends when both the probes have reached
or exceeded their respective end of
defrosting set points (dSt for the 1st evap-
orator and dS2 for the 2nd evaporator).
If one or both the probes are faulty,
defrosting is ended by a time-out.
NOTE:
• If there are no conditions for defrosting,
the request is ignored. Defrosting of a sin-
gle evaporator ends when the value read
by the respective probe is equal to or
higher than the end of defrosting temper-
ature or a time-out occurs. Dripping starts
when both defrosts have been completed.
• If one or both the probes are faulty,
defrosting in the corresponding evaporator
is ended by a time-out. The start of
defrosting is permitted when the corre-
sponding temperature is lower than the
corresponding set point (dSt or dS2).
• If probe 3 is not configured as a probe
on the second evaporator (H43
≠
2),
defrosting on the second evaporator
occurs if a digital output is configured to
control defrosting on the second evapora-
tor (see par. H21..H25). If this is the case,
defrosting is confirmed (as if ST3<dS2)
and ends with a time-out. The fan con-
troller remains unchanged.
DIAGNOSTICS
The alarm condition is always signalled by
a buzzer (if present) and the alarm icon
LED. The alarms from the faulty thermo-
stat control probe (probe 1), the faulty
evaporator probe (probe 2), and the faulty
display probe (probe 3) appear directly on
the instrument display as E1, E2, and E3
respectively.
An error condition in probe 1 (thermostat
control) causes the following:
• E1 code appears on display
• compressor is activated as indicated by
“Ont” and “Oft” parameters if these are
programmed for duty cycle or: The error
condition for probe 2 (evaporator) causes
the following:
• E2 code appears on display
• end of defrost due to time-out. The
error condition for probe 3 (display) caus-
es the following:
• E3 code appears on display Other alarms
do not appear on the instrument display
but can be seen in the “Machine Status”
menu in the “AL” folder.
The maximum and minimum temperature
alarm is regulated according to the ther-
mostat control probe (probe1) and/or dis-
play probe (probe 3). The temperature
limits are defined by the “HAL” (maximum
alarm), “LAL” (minimum alarm) and PbA
(alarm configuration on probe 1,3 or both)
parameters.
MAXIMUM AND MINIMUM TEMPERA-
TURE ALARM
If an alarm condition occurs and alarm
exclusion times are not running (see alarm
exclusion parameters), the alarm icon lights
up permanently and the relay configured
as an alarm is activated. This type of alarm
does not affect the regulating in progress.
Alarms are considered as absolute
(default) values or as values related to the
Set point (the distance from the Set point
itself) and based on the Att parameter. If
the alarms are relative (Att=1), the para-
meter HA1 is set to positive values and
LA1 to negative values.
This alarm condition can be viewed in the
folder “AL” with labels “AH1-AL1”.
ALARM WITH THRESHOLD (PROBE 3)
By setting the PbA=3 parameter an alarm
is associated to probe 3. It refers to a spe-
cific threshold (defined by the SA3 para-
meter). An over-temperature or an under-
temperature alarm is generated and the
icon is turned on. This alarm condition can
be viewed in the “AL” folder with the
labels “AH3-AL3”.
The alarm is handled as a temperature
alarm for probe 3: for delays and back-
swings, refer to standard alarms
DEFROST ALARM
If the end of defrosting is due to a time-
out (rather then because an end of
defrosting temperature is detected by the
defrosting probe), an alarm is generated
and the icon lights up.
This condition can be viewed in the “AL”
folder with the label “Ad2”. Automatic
back swinging occurs when the next
defrost starts. By pressing any button dur-
ing the alarm condition, the signal light dis-
appears. In order to cancel the alarm prop-
erly, you must wait until the next defrost.
EXTERNAL ALARM
The device can also control an external
alarm, i.e. from a digital input. If the digital
input is enabled, the alarm control is acti-
vated by programming and remains
enabled until the next time the digital
input is deactivated. When an alarm is set
off, the alarm icon lights up permanently,
the relay configured as alarm is activated
and the compressor, defrost and fan con-
trollers are deactivated (if specified by the
“EAL” parameter). This alarm condition can
be displayed in the “AL” folder using the
“EA” label. The relay can be silenced; even
if the alarm icon starts blinking, the con-
trollers remain locked until the next time
the digital input is deactivated.
OPEN DOOR ALARM
If a door is open, the Open Door alarm is
signalled in response to a delay defined by
the tdO parameter. The alarm is signalled
by the flashing alarm icon. This alarm con-
dition can be viewed in the “AL” folder
with the label “Opd”.
LINK ALARM
If there is a master/slave/echo communi-
cation failure, the No Link alarm is sig-
nalled. This alarm condition can be viewed
in the “AL” folder with the label “E7”.
NOTE:
•The E7 error is signalled after approx. 20
seconds in “no link” condition to avoid any
link disturbance causing communication
errors.
•The E7 error is also signalled for address-
ing conflicts when:
a) the number of Slaves set on the MAS-
TER is different from the actual number of
Slaves on the network
b) 2 or more Slaves have the same
address.
ID 983-985 LX (/C /CK) HACCP
4/12
Ont
0
0
>0
>0
Oft
0
>0
0
>0
Compressor output
OFF
OFF
ON
dc
DISPLAY
E1
E2
E3
If simultaneous, they will be shown on the display
alternately every 2 seconds
FAULT
Faulty probe 1 (thermostat control)
Faulty probe 2 (1st evaporator)
Faulty probe 3 (display or 2nd evap-
orator)
Table of faulty probes
