Page 0 - IOM / @DNOVA-µAC-0907-E
Pd Return-supply temp. difference for supply temperature
alarm
Sets the minimum difference between the return temperature
(measured by B1) and the supply temperature (measured by
B4) for the activation of the cooling function alarm (At). This
alarm has a fixed delay of 4 minutes.
n.B.
For alarm At to be generated, the following conditions
must all be satisfied:
1. Supply temp. > Return temp. - Pd that is B4 > B1-Pd.
2. At least one compressor on or cooling valve open more
than 50%.
3. Both heating elements off or heating valve closed.
4. Delay time of 4 minutes has elapsed.
When this alarm is detected, only the active compressor is
blocked.
Range: 0÷20°c 0÷36°F Def.: 3
Pe ID4 input selection
If = 1 instead of the heating element thermal overload alarm it
activates a smoke-fire alarm.
Range: 0÷1 flag Def.: 0
PF ID49 input selection
If = 1 in the CW machines, it activates a water flow alarm.
Range: 0÷1 flag Def.: 0
PG High temperature prealarm enabling
It enables the “ht” prealarm with a differential from the set equal
to P7/2 and hysteresis of 1 degree (in this case it is better to
increase the P7 value).
Range: 0÷1 flag Def.: 0
H= general configuration parameters
H1 Machine model
Sets the type of air-conditioning unit to be controlled.
0= eD unit (see par. 4.2)
1= cW unit (see par. 4.1)
2= cW unit (c/H)
3= shelter unit (see par. 4.3)
For models CW and ED, the configuration is determined by
parameters H5 and H6; for models CW C/H and shelters, on
the other hand, it is set according to the cooling actuators.
cW c/H:
machine using refrigerated water with central cooling/
heating switching. In heating mode the battery is supplied with
hot water, and the cooling valve is used for regulation. Input
ID7 performs the switching from heating to cooling and the
exchange of the set-point, as
follows:
ID7= 24Vac Heating set= r9
ID7= 0 cooling set= r1
When the machine is in cooling mode, the presence and the
number of heating elements depends on parameter H6; in
heating mode, on the other hand, the cooling actuators are
considered absent and the heating elements inhibited.
shelters:
direct expansion machine with 1 compressor,
1 heating element (optional - H6), condensation control,
damper management for free-cooling and no power alarm
(no humidifier control possible). For the configuration of the
inputs and outputs.
Range: 0÷3 flag Def.: 0
H2 number of machines in rotation
H2 is setting at 0 in stand alone machine. Enables the rotation
function of a unit in stand-by within a group of H2 units (H2=1
no meaning). The value of H2 in fact specifies the total number
of units connected according to the diagram in par. 4.4 on
p. 10. Only one unit is in stand-by, while the others are in
operation. Once the time H4 has elapsed, the rotation of the
unit in reserve occurs, according to the progressive order of
the addresses. If one of the units in operation stops, due to an
alarm, the machine in stand-by is automatically re-activated.
The alarm condition is detected after a delay of 30s.
Range H2: 0÷6 flags Def. H2: 0
H3 Address of unit in rotation
Specifies the address of the unit; if two units have the same
address they are placed in stand-by together. The unit with
address 1 is the master, and this unit, with impulses transmitted
via digital output Out7, sends the other units the command to
switch from ON => STAND-BY and vice-versa. This command
is re-sent every 10 minutes.
Range H3: 1÷6 Def. H3: 1
H4 Rotation time between a series of units
Sets the rotation interval, after which the unit off is turned on,
while the unit with the subsequent address goes to stand-by.
Setting H4= 0 activates test mode, with a rotation time of 2
mins. This operating mode is indicated by the letter “C” in the
“day field” on the display.
Range H4: 0÷250 hours Def. H4: 0
DESCRIPTION AND CONFIGURATION OF THE PARAMETERS
