Ascon tecnologic e34B User Manual

Ascon Tecnologic - e34B - OPERATING INSTRUCTIONS - PAG. 11
perature is high, parameter DtS allows to set the temperature
related to the EP probe under which defrosts are possible.
Therefore, in the indicated modes, if the temperature meas-
ured by the EP probe is higher than the one set at parameter
dtS and also dtE defrosts are inhibited.
dtE
dts
Defrost
dF
offoffoff
ON ON
AB
Temp.
time
C
(NO defrost)
dde
ddi/dSd
(Defrost)
ddi/dSd
ddi/dSd ddi
(Defrost)
EP
Example: Defrost A ends due to reaching of temperature
dtE, defrost B ends at the end of the ddE time as the
temperature dtE is not reached, defrosting C does not take
place as the temperature is higher than dts.
dtE
dts
offoffoff off
ddi/dSd
ON ON ON
time
ddi
(Defrost)
dde
1°
Defrost
dF
Temp.
EP
Example of electric defrost with evaporator temperature
control: the defrost end after ddE programmed time. During
defrost the dF output switch ON/OFF to control evaporator
temperature in heating mode with set point dtE and 1° dif-
ferential (Hysteresis).
The active defrost is shown on the instrument display with
the lighting up of the LED .
At the end of defrosting, it is possible to delay the new com-
pressor start up (output ot) at the time set in parameter dtd
to allow the evaporator to drain. During this delay, the LED
flashes to indicate the draining state.
5.8.4 Intervals and defrosts duration in case of
evaporator probe error
In event of evaporator probe error the defrosts occur at inter-
vals dEi and duration dEE.
In case an error occurs when the time remaining to the start
or the end of defrost is lower than the one normally set with
the parameters related to error probe conditions, the start or
the end takes place with the shortest time.
These functions are provided because when the EP evapo-
rator probe is used, the set defrost endurance time is usually
longer than necessary (the time ddE is a security time-out)
and in case is used the “Dynamic Intervals Defrost System”
the interval is usually set more longer than what is normally
programmed into instruments that do not have the function.
5.8.5 Display lock during Defrost
Through parameters ddL and AdA it is possible to define the
display behaviour during defrost:
on The ddL parameter locks the display at the last Pr1
temperature reading during all the defrost cycle until,
at the end of defrost, the temperature has not reached
the lock value or the value [SP + rd] or is elapsed the
time set at parameter AdA;
oF The display continues showing the temperature meas-
ured by the Pr1 probe during the defrost cycle.
5.9 Evaporator fans control
The control of the evaporator fans on the output configured as
Fn depends on some specific control statuses of the instrument
and the temperature measured by the evaporator probe (EP).
In the case that the evaporator probe is not used or in error,
the Fn output is activated only depending on parameters
Ftn, FtF and FFE.
Parameters Ftn and FtF can be used to determine the behavior
of the evaporator fans when the ot outupt (compressor) is OFF.
When ot output is OFF, it is possible to set the instrument so
that that the Fn output continues working in cycles according
to the times programmed at parameters Ftn (fan activation
time) and FtF (fan deactivation time).
When output ot is switched OFF the instrument activates the
output Fn for the time Ftn, then deactivates it for the time
FtF and so on whilst the otuput ot remains OFF.
Programming Ftn = oF the output Fn in ot OFF condition
remains switched OFF.
Programming instead Ftn to any value and FtF = oF the
output Fn when ot in OFF condition remains switched ON.
The parameter FFE decides whether the fans must always
be switched ON independently of the defrosting status
(FFE = on) or switched OFF during defrosting (FFE = oF).
In this later case, it is possible to delay the start up of the
fans even after the end of the defrost by the time set at FFd
parameter. When this delay is active the LED flashes to
point out that the FFd delay is in progress.
When the evaporator probe is used the fans, as well as be-
ing conditioned by the parameters Ftn, FtF and FFE, are
also conditioned by a temperature control.
FLF
FFL
Temp.
FdF
FdF
time
offoff offON ON
Ep
Fan
Note: 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
evaporator fans stops also the thermal exchange.
Remember that the fans functioning can be conditioned by
the Door open function by the digital input.

Ascon tecnologic e34B Specifications

General

Brand	Ascon tecnologic
Model	e34B
Category	Temperature Controller
Language	English