OSAKA
- OF 33 AZ - OPERATING INSTRUCTIONS - Vr. 01 - PAG. 5
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
“
]
PrC”.
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.
This function foresees a time control on the switching on of the
“Out” output associated with the temperature regulation
request.
The protection consists of preventing the output being switched
on during the time set in the parameter
“PtC”
and counted
depending on what has been programmed in the parameter
“PSC”
, and therefore that any activation occurs only after the
“PtC” time has finished.
If during the power on delay phase, the regulator request
should disappear, due to an inhibition caused by the
compressor protection function, the foreseen start up of the
output is naturally cancelled
.
Using the parameter
"PSC", it is possible to set the type of
compressor protection and therefore from when the inhibition
time “PtC” must start.
The parameter “PSC” can be set as:
= 1
: Power on delay
T e m p .
O u t
P t C
o f f
O N
S P
P t C
P t C
" P S C " = 1
t i m e
H S E t
o f f
o f f
o f f
O N
O N
P r 1
= 2
: Delay after power off
O N
O u t
o f f
P t C
P t C
P t C
S P
T e m p .
" P S C " = 2
t im e
H S E t
O N
O N
o f f
o f f
P r 1
= 3
: Delay between power on phases.
P t C
O u t
o f f
S P
O N
T e m p .
P t C
P t C
t i m e
H S E t
" P S C " = 3
o f f
o f f
O N
O N
P r 1
The function is disabled by programming “PtC” = 0.
Through the parameter
“LCt”
it is also possible to set the
minimum activation time of the output to avoid switching on of
the compressor that is too short.
During the power on delay phases of the OUT output by
inhibiting the function “Compressor Protection” or delay of
power off caused by the minimum function time “LCt”, the led
OUT flashes.
It is also possible to prevent activation of all the outputs after
the instrument is turned on, for the time set in the parameter
“od”
.
The function is disabled by “od” = OFF.
During the power on delay phase, the display shows the
indication
od,
alternating with the normal programmed
visualisation.
4.6 - DEFROST CONTROL
All the parameters concerning the defrosting control that acts
on the outputs configured as “Out” and “dEF”, are container in
the group
“
]
dEF”.
The type of defrosting that the instrument must carry out is set
by the parameter
“dtyP”
that can be programmed:
= EL
- WITH ELECTRICAL HEATING or BY STOPPING
COMPRESSOR (during defrosting, the output “Out” is
deactivated while the output “dEF” is enabled)
= in
- WITH HOT GAS or INVERSION OF CYCLE (during
defrosting the outputs “Out” and “dEF” are enabled)
The automatic defrosting can take place at intervals or if the
instrument has an internal clock, at set hours.
Defrosting at intervals is possible by setting the time that runs
between the two next automatic defrostings in the parameter
“dint”
.
Counting this interval is set through the parameter
"dCt"
that
can be programmed:
= rt
- counts the total function time (instrument on)
= ct
- counts only the compressor function time (output OUT
switched on)
= cS
- the instrument carries out a defrosting cycle at each
compressor stop (i.e. at each deactivation of the output OUT).
If this option is used, set “dint”=OFF.
if the instrument has an internal clock, it is possible to carry out
up to 6 defrostings per day at set times.
To use this mode, it is necessary to set the parameter
"dint"=OFF so that the defrosting at intervals is disabled and to
set the parameters
“dF 1”, “dF 2”, “dF 3”, “dF 4”, “dF 5”,
“dF 6”
with the times when the defrosting must be carried out.
The automatic defrosting cycle can be at time intervals or, if an
evaporator probe is used (Pr2), when a temperature is reached.
If the evaporator probe is not used (par. “Pr 2” = OFF) the
duration cycle is set by the parameter
“dEFE”.
If instead the evaporator probe is used (parameter “Pr 2” = on)
the defrosting takes place when the temperature measured by
the probe exceeds the temperature set in the parameter
“tEdF”.
If this temperature is not reached in the time set in the
parameter “dEFE”, defrosting is interrupted.
In order to avoid pointless defrosting the parameter.
“tSdF”
is
foreseen that sets the enablement temperature for defrosting
If the temperature measured by the probe is higher than the
one set in the parameter
“tSdF” and in the parameter "tEFE"
the defrosting is inhibited.
( N O d e f . )
( d e f r o s t )
t E d F
d E F
o f f
O N
t S d F
d in t
1
P r 2
T e m p .
( d e f r o s t )
d in t
d E F E
2
d in t
d in t
3
t im e
o f f
o f f
O N
Examples:
defrosting 1 ends due to reaching of temperature
“tEdF”, defrosting 2 ends at the end of the “dEFE” time as the
temperature “tEdF” is not reached, defrosting 3 does not take
plac
e as the temperature is higher than “tSdF”.
At the end of defrosting, it is possible to delay the new start up
of the compressor (output “Out”) at the time set in parameter
“tdCO”
to allow the evaporator to drain.
During this delay, the led Def flashes to indicate the draining
state.
It is also possible to prevent start up of the compressor near to
defrosting, to avoid waste of energy.
If inside the time set in the parameter
“COFd”
(counted in
advance compared to the start up of automatic defrosting both
at intervals and by clock), an activation request for the output
“Out” should take place, this does not take place and it is
signalled by the flashing of the Out led.
