Technical Manual Cold Storage Controller EVP 3150-1 and EVP 3150-2
Page 8
Second setpoint
(night operation)
A second setpoint can be defined by "
r03
" (Setpoint
Page). This can be used for night operation or other
energy savings. Switching between these setpoints
can be made by internal clock or by digital input. The
current used setpoint is marked by a lighted decimal
point in the parameter display. On the 'Actual Values
Page', parameter "
L43
" shows the current state.
Internal switching
The parameters „
P21
“ and „
P22
“ determine
the 2nd setpoint period. If the internal timer is not
used, set both times to "
oFF
".
External switching
The digital inputs can be configured for
external switching, selectable as "
dnL
"
(active low) or "
dnh
" (active high). After the
input has been activated, the 2nd setpoint is
active all time and the internal timer is disabled.
If you want to use external switching only,
please set „
P21
“ and „
P22
“ to "
oFF
".
Second Set of Setpoints
The controller offers two complete setpoint sets
including day/night setpoints and alarm limits.
Example Application: By an external switch it is
possible to change a cold room from refrigeration
to freezing for temporary storage of other products,
without changing any parameters at the controller.
Even here the currently used setpoint is marked by
a lighted decimal point in the parameter display.
Toggling between the setpoint layers
1. internal: by parameter „
r01
“ (Setpoint Page)
2. external: assign function „
SEt
“ to a digital
input. If connected to mains phase,
the 2nd layer is in use.
Light Control
One of the relays is able to control room lightings
(function "
LIt
"). In this case, the relay switches
together with the night settings.
While 'day'-operation the light relay keeps ener-
gized.
Emergency Operation
If all control sensors fail, the unit turns to an
emergency mode automatically. The cooling relay
cycles with a %-part (
P04
, Mode Page) of a 30
minutes period.
Digital Inputs
(Optocoupler Inputs)
Switching OFF the controller unit
Sometimes it is necessary to switch off cold storages
completely including the controller.
If the controller works in a network, the bus-master
so detects a malfunction and generates an alarm.
To prevent this, the unit must be switched OFF via
digital input.
Controller OFF
If a digital input is assigned to the functions "
oFL
"
or "
oFH
" and is activated by the matching signal,
then all control functions will be disabled. All alarm
functions are locked and the display shows "
oFF
".
Safety Chain Monitoring
When using the controller for single compressor
applications, one of the digital inputs can be used
to monitor the safety chain ("
chA
").
Normally the digital input is connected to phase via
this chain of contacts. If the chain opens, cooling
and fan will switch off, a running defrost cycle will be
terminated and a new defrost cycle is impossible.
Parameter "
r46
" defines the response time on the
missing signal voltage.
Door Contact Input
If a digital input with the function "
dor
" is connected
to phase, the evap fan stops immediately. The control
range of the EEx-Valve will be changed automatically
to avoid a further evaporation.
If the door is open
> 3 minutes
, cooling will be
stopped. All other functions continue working.
If the door is open
> 5 minutes
, the unit generates the
error message "
rdo
". After the timer "
r62
" (Setpoint
Page) has been run down, cooling restarts and an
alarm message will be forwarded.
Door open monitoring
Every time a door is opened, the controller adds
the time to the total opening time of the present day
"
L22
" (Actual Values Page). If the total opening time
exceeds the value set by "
r32
" (Setpoint Page), an
alarm will be generated.
The alarm message will be forwarded at the point in
time determined by "
P42
" (Mode Page) and will be
cancelled automatically 1 hour later. "
L31
" shows
the remaining time up to the alarm message.
External Alarm
The digital inputs are able to process external alarm
messages. For this, the function "
ALA
" must be
assigned (Assignment Page).
While normal operation, the input is connected to
mains phase. When the voltage drops down, a delay
time starts ("
r61
", Setpoint Page). After this timer has
been run down, an alarm will be forwarded.
Exception:
If no alarm sensor is assigned or if
the temperature is above the alarm
limit, cooling continues without inter-
ruption. The cooling keeps switched
ON and the fan starts again, so the
door opening is ignored.
Real Time Clock
The built-in real time clock has a buffer for max. 10
days without mains voltage. Date and time can be
set by "
P82
"..."
P87
" (Mode Page).
An automatic summer / winter switch ("
P81
", Mode
Page) considers the current EU-rules from 1996 (EU
96), but can also be switched off.
30 minutes
emergency ON
in %
ON
OFF
cooling OFF
cooling ON
