Carel EVD Evolution Twin, User Manual

Page: 62 / 68

ENG
“EVD Evolution TWIN” +0300006EN - rel. 2.6 - 31.01.2019 62
TA PA
E
L
F
S
V
CP
M
S1
EVD
evolution
S2
EV
POWER +
speed drive
RS485
Modbus®
0V + -
1 2 3
TB
PB
S3 S4
Tx/Rx GND
shield
pCO
GND
shield
C
Fig. 13.d
Legenda:
CP Compressor V Solenoid valve
C Condenser S Liquid gauge
L Liquid receiver EV Electronic valve
F Dewatering filter E Evaporator
TA,TB Temperature probes PA, PB Pressure probes
For information on the wiring see paragraph “General connection diagram”.
To optimise performance of the refrigerant circuit, compressor operation
must always be inside a specific area, called the envelope, defined by the
compressor manufacturer.
Inviluppo ⁄ Envelope
Temperatura di evaporazione (C°)
Evaporation temperature (C°)
Temperatura di c
ondensazione (
C°)
C
ondensing temper
atur
e (
C°)
Fig. 13.e
The pCO controller defines the current set point according to the point of
operation within the envelope:
•
superheat setpoint;
•
discharge superheat setpoint;
•
discharge temperature setpoint.
Parameter/Description Def. Min. Max. UOM
ADVANCED
Superheat setpoint
11 LowSH:
threshold 180(324) K(°F)
Discharge superheat setpoint 35 -40(-72) 180(324) K(°F)
Discharge temperature setpoint 105 -60(-76) 200(392) °C(°F)
Tab. 13.g
Note
:
this control function is only available CAREL valve drivers; no set point needs
to be configured by the user.
S uperheat regulation with 2 temperature probes
The functional diagram is shown below. This type of control must be used
with care, due to the lower precision of the temperature probe compared to
the probe that measures the saturated evaporation pressure.
Parameter/Description Def.
CONFIGURATION
Main control
…
superheat regulation with 2 temperature
probes
multiplexed showcase/cold
room
C
T
E
L
F
S
V
CP
M
S4
EVD
evolution
S2
EV
T
Fig. 13.f
Key:
CP Compressor V Solenoid valve
C Condenser S Liquid gauge
L Liquid receiver EV Electronic valve
F Dewatering filter E Evaporator
T Temperature probe
Parameter/Description Def. Min. Max. U.M.
ADVANCED
Superheat setpoint
11 LowSH: soglia 180 (324) K (°F)
PID: proportional gain 15 0 800 -
PID: integral time
150 0 1000 s
PID: derivative time 5 0 800 s
Tab. 13.h
13.9 Auxiliary control
Auxiliary control can be activated at the same time as main control, and uses
the probes connected to inputs S3 and/or S4.
Parameter/description Def.
CONFIGURATION
Auxiliary control:
1=Disabled;
2=High condensing temperature protection on S3 probe;
3=Modulating thermostat on S4 probe;
4=Backup probes on S3 & S4;
5, 6, 7 = Reserved;
8 = Subcooling measurement;
9 = Reverse high condensing temperature protection on S3
Disabled
Tab. 13.i
For the high condensing temperature protection (only available with
superheat control), an additional pressure probe is connected to S3 that
measures the condensing pressure. For the modulating thermostat function
(only available with superheat control), an additional temperature probe
is connected to S4 that measures the temperature on used to perform
temperature control (see the corresponding paragraph).