4 - FUNCTIONS
4.1 - MEASURING AND VISUALIZATION
All the parameters concerning measuring are contained in the
group
“-in”.
Via the parameter
“SE”
it is possible to select the type of probes
that one wishes to use and which can be: thermistores PTC
KTY81-121 (Pt) or NTC 103AT-2 (nt).
Once the type of probe used has been selected, through the
parameter
“ru”,
it is possible to select the temperature unit of
measurement (°C or °F) and, through the parameter
“dP”
, the
resolution of the desired measurement (oF=1°; on =0,1°).
The instrument allows the measuring to be calibrated, that can be
used for re-calibrating the instrument according to application
needs, through the parameters
“C1”
(for the probe Pr1) and
“C2”
(for the probe Pr2).
Through the parameter
“i.CU”,
it is possible to program an measu-
re offset that will be applied to the Pr1 temperature show .
All the controls will always happen in operation of the measure
corrected only by the calibration parameters (“C1”).
If probe Pr2 (evaporator) is not used, set the parameter
“P2”
= oF.
Using the parameter
“Ft”,
it is possible to set the time constant for
the software filter for measuring the input values to be able to
reduce the sensitivity to measurement disturbances (increasing the
time).
Through the paragraph
“dS”,
it is possible to fix the normal
visualisation on the display that can be the measurement of the cell
probe (P1), the measurement of the evaporator probe (P2) or the
set point of active regulation (SP).
Regardless of what is set in the parameter “dS”, it is possible to
visualise all the variables in rotation by pressing the key
U
, the
display will alternately show the code that identifies the variable
(
P1
,
P2)
and its value.
The exit of this visualisation mode occurs automatically 15 seconds
after the last pressing on the key U.
If the instrument is equipped with the voltage alarms in this mode
will be displayed the variable P3 that represents the main voltage
with a value decreased of 150 V.
The main voltage tension measured by the instrument will be
therefore V = P3 + 150.
If the voltage measure is not correct it is possible to modify it
through the par.
"OU"
present in the group
"- Pr."
Please remember that visualisation of the probe Pr1 can be
changed by the display block in defrosting function too, by using
the parameter “dL” (see Defrost function).
4.2 - OUTPUTS AND BUZZER CONFIGURATION
The instrument outputs can be configured in the parameters group
“-ot”
where the relative parameters
“o1” , “o2”, “o3”, “o4”
are
found.
The outputs can be configured for the following functions :
= Ot
- to control the compressor or however, the temperature
control device
= dF
- to control the defrosting device
= Fn
- to control the fans
= Au
- to control the auxiliary device (see par. 4.11)
= At
- to control a silenceable alarm device through a contact that
is normally open, and then closed when the alarm sounds
= AL
- to control an alarm that cannot be silenced through a
contact that is normally open and closed when the alarm sounds.
= An
- to control an alarm with a memory function through a
contact that is normally open and closed when the alarm sounds.
= -At
- to control a silenceable alarm device through a contact that
is normally closed, and then open when the alarm sounds.
= -AL
- control an alarm that cannot be silenced through a contact
that is normally closed and open when the alarm sounds.
= -An
- to control an alarm with a memory function through a
contact that is normally closed and open when the alarm sounds
(see alarm memory).
= oF
- Disabled output
The internal buzzer (if present) can be configured by par.
“bu”
for
the following functions:
oF
= Buzzer always disable
1
= Buzzer signal active alarms only
2
= Buzzer signal key pressed only (no alarm)
3
= Buzzer signal active alarms and key pressed
4.3 - TEMPERATURE CONTROL
All the parameters concerning temperature regulation are
contained in the group
“-rG”.
The regulation of the instrument is ON/OFF and acts on the output
configured as “Ot” depending on the measuring of probe Pr1, of the
active Set Point
“SP”
(SP, S2, S3, S4), the intervention differential
“d”
and the function mode
“HC”
.
Depending on the function mode programmed on the parameter
“HC” the differential is automatically considered by the regulator
with positive values for a Refrigeration control (“HC”=C) or with
negative values for a heating control (“HC”=H).
Ot
SP
off
ON
HC=H
Ot
time
d
SP
Temp.
d
time
HC=C
ON
ON
ON
ON
ON
off
off
off
Pr1
Pr1
Temp.
In the event of cell probe error (Pr1), it is possible to set the
instrument so that that the output “Ot” continues to work in cycles
according to the times programmed in the parameter
“t1”
(activation time) and
“t2”
(deactivation time).
If an error occurs on the probe Pr1 the instrument activates the
output for the time “t1”, then deactivates it for the time “t2” and so
on whilst the error remains.
Programming “t1” = oF lthe output in probe error condition will
remain switched off.
Programming instead “t1” to any value and “t2” = oF the output in
probe error condition will remain switched on.
Remember that the temperature regulation function can be
conditioned by the “Continuous Cycle”, “Compressor Protection”,
“Minimum compressor function time”, “Delay compressor start up
after defrosting” and “inhibition of compressor close to defrosting”
functions described below.
4.4 - CONTINUOUS CYCLE FUNCTION
The instrument has a continuous cycle function by which it is
possible to maintain the configured output configured as “Ot”
always active for the time set in parameter
“tC”
(in the group “-rG”)
regardless of the temperature control command.
The function can be used for example, when rapid lowering of the
product temperature is required after the refrigerator loading
phase.
During the continuous cycle, the defrosting is inhibited and the
temperature alarms are disabled during the entire cycle and also
later for the time set in parameter
“cA”
(see par. 4.9).
Starting up a continuous cycle can only be done by a manual
command using the U or DOWN/AUX (“UF” or “Fb” = 2) keys or via
the digital input (“FI”=3) if suitably programmed (see par. 4.10 and
4.12).
The continuous cycle in progress is shown on the display with the
indication
CC
and can be stopped by a further action on the key or
digital input (as for activation).
The continuous cycle function cannot be activated during
defrosting and with "tC" = oF.
4.5 - COMPRESSOR PROTECTION FUNCTION AND DELAY AT
POWER-ON
All the parameters concerning the compressor protection functions
and the delay at power on are contained in the group
“-Pr”.
The function “Compressor Protection” carried out by the machine
aims to avoid close start ups of the compressor controlled by the
instrument in cooling applications.
ASCON TECNOLOGIC - TLB55
- OPERATING INSTRUCTIONS - Vr. 04 - 02/12 - ISTR-MTLB55ENG04 - PAG. 4
