The start up or switch off commands of a defrosting cycle can also
be given by the digital input that are correctly programmed (see
par. 4.10).
4.8 - EVAPORATOR FANS CONTROL
All the parameters concerning fan control are contained in the
group
“-Fn”.
The control of the fans on the output configured as “Fn” depending
on determined control statuses of the instrument and the
temperature measured by the probe Pr2.
In the case that the probe Pr2 is not used (parameter “EP” = oF) or
in error (E2 o -E2) , the output Fn is activated only depending on
the parameters “FC” and “FE”.
The parameter
“FC”
decides whether the fans must always be
switched on independently of the compressor status (“FC”=on) or
be switched off together with the compressor (“FC”=oF).
The parameter
“FE
” instead decides whether the fans must always
be switched on independently of the defrosting status (“FE”=on) or
switched off during defrosting (“FE”=oF).
In this latter case, it is possible to delay the start up of the fans
even after the end of the defrosting of the time set in the parameter
“Fd”.
When the probe Pr2 is used (par. “EP” = on) the fans, as well as
being conditioned by the parameters “FC” and “FE”, are also
conditioned by the temperature control.
It is possible to set the disablement of the fans when the
temperature measured by the probe Pr2 is higher than the one set
in the parameter
“FL”
(temperature too hot) or when it is lower
than the one set in the parameter
“LF”
(temperature too cold).
The relative differential that can be set in parameter
“dF”
is also
associated with these parameters
.
d F
d F
t i m e
F n
o f f
O N
L F
P r 2
T e m p .
F L
o f f
o f f
O N
Notes: It is necessary to pay attention to the correct use of this fans
temperature control functions because in the typical application of
refrigeration the stop of the fans evaporator stops thermal
exchange.
Remember that the fans functioning can be conditioned by the
“Door open” function by the digital input.
4.9 - ALARM FUNCTIONS
All the parameters concerning the alarm functions are contained in
group
“-AL”.
The alarm functions of the instrument work on the output desired, if
configured by the parameters “o1”, “o2”, “o3”, “o4” depending on
what is set on the said parameters.
The possible selections of these parameters for the alarm
signalling function are:
= At
- when one wants the output to be activated in alarm and can
be disabled (alarm silencing) manually by pressing any key of the
instrument (typical application for sound signal).
= AL
- when one wants the output to be activated in alarm status
but cannot be disabled manually and are therefore only disabled
when the alarm status ceases (typical application for a light signal).
= An
- when one wants the output to be activated in alarm status
and that they remain activated even when the alarm has ceased
(see par.4.9.5) Disablement (recognition of memorised alarm) can
only be carried out manually by pressing any key when the alarm
has ended (typical application for light signal).
= -At
- when one wants the function described as At but with an
inverse function (output activated in normal condition and disabled
in alarm status).
= -AL
- when one wants the function described as AL but with
inverse logic (output activated in normal conditions and disabled in
alarm status).
= -ALL
- when one wants the function described as An but with
inverse working logic (output activated in normal conditions and
disabled in alarm status).
The alarm conditions of the instrument are:
- Probe errors “E1”, “-E1”, “E2, “-E2”
- temperature alarms “HI” and “LO”
- External alarms “AL”
- Open door alarm “oP”
- Low or High Main voltage alarms “UL” (if the instrument is
equipped with voltage alarms functio n)
4.9.1 - TEMPERATURE ALARMS
The temperature alarms work according to the probe Pr1
measurements, the type of alarm set in the parameter
“Ay”
the
alarm thresholds set in parameters
“HA”
(maximum alarm) and
“LA”
(minimum alarm) and the relative differential
“Ad”.
Through the parameter “Ay” it is possible to set the alarm
thresholds “HA” and “LA” which must be considered as absolute
(“Ay”=Ab) or relative to the active Set Point (“Ay”=dE).
Using some parameters it is also possible to delay the
enablement and the intervention of these alarms.
These parameters are:
“PA”
- is the temperature alarm exclusion time on switching on the
instrument if the instrument is in alarm status when it is switched
on.
“dA”
- is the temperature alarm exclusion time at the end of
defrosting (and , if programmed, at the end of draining)
"cA"
- is the temperature alarm exclusion time at the end of a
continuous cycle.
“At”
- is the temperature alarm delay activation time
The temperature alarm is enabled at the end of exclusion time and
is enabled after the “At” time when the temperature measured by
the probe Pr1 exceeds or goes below the respective maximum and
minimum alarm thresholds.
The alarm thresholds will be the same as those set on the
parameters “HA” and LA” if the alarms are absolute (“Ay”=Ab).
A d
A d
tim e
A L
o ff
O N
L A
H I
H A
T e m p .
P r1
L O
o ff
o ff
O N
or will be the values [”SP”+”HA”] and [”SP”-”LA”] if the alarms are
relative (“Ay”=dE).
tim e
A d
A d
A L
o ff
O N
H I
L A
S P
H A
T e m p .
P r1
L O
o ff
o ff
O N
The maximum and minimum temperature alarms can be disabled
by setting the relative parameters "HA" and "LA" = oF.
At the same time as the signalling of the configured alarm output,
the instrument visualises on the display:
- Alternately
HI
and the set variable in parameter “dS” for maximum
alarm
- Alternately
LO
and the set variable in parameter “dS” for the
minimum alarm
ASCON TECNOLOGIC - TLB55
- OPERATING INSTRUCTIONS - Vr. 04 - 02/12 - ISTR-MTLB55ENG04 - PAG. 6
