Smooth Lines On Mpxpro: Confi Guration - Carel PVPRO Mode D'emploi

ENG
If the Smooth lines function is enabled, the algorithm tells the supervisor whether the MPXPRO is operating
with a certain margin, i.e., the suction pressure set point on the corresponding line can be increased wi-
thout jeopardising control. In detail, the MPXPRO declares that operation is suitable if the average working
superheat set point is higher than P3 + THS. The average is calculated inside the time window FSt.
Working setpoint
Superheat setpoint (P3)
Regulation temperature
Regulation setpoint
Cooling request
1
0
Smooth line status
1
0
1.2 Smooth lines on MPXPRO: confi guration
The Smooth lines confi guration parameters are listed in Table 1. The basic settings are listed below, with the
parameter name and default value:
enable function, default value is PSM = 0 (disabled);
1.
set maximum superheat off set, default value is PHS = 15 (K);
2.
set compressor cut-off off set, default value is PLt = 2 (K);
3.
set main control diff erential, default value is rd = 2 (K);
4.
if smooth lines is enabled, the suggested value is rd = 4 (K).
+030220575 - 1.1 - 04.12.2014
As soon as the regulation temperature falls below the
setpoint + rd/2, an offset will be added to the superheat
setpoint in order to reduce the EXV valve opening.
Cooling status will stay active until the regulation
tewmperature does not fall below the threshold St - PLt.
When the average of working setpoint is higher
than the threshold P3 + TSH the Smooth line status
becomes 0, allowing suction pressure rising.
t t1 t2
FSt = average time window (min)
Fig. 1.b
6
PHS = max superheat offset
rd/2
PLt = offset under setpoint
t3 t4 t5
TSH = superheat threshold
rd = setpoint differential