10
ENG
“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018
2.3 Wiring diagram for superheat control
•
EVD mini requires the use of an evaporation pressure probe S1 and
suction temperature probe S2, which will be fitted downstream of
the evaporator, and a digital input to enable control. Alternatively, the
signal to enable control can be sent via a remote RS485 connection;
•
input S1 is programmable and connection to the terminals depends
on the parameter settings. See the chapters “Commissioning” and
“Functions”.
Note:
for details on installing probes, see the “EEV system guide”
(+030220810).
GAS Type
Mode
Super Heat
GND
Tx/Rx+
Tx/Rx-
G
G0
DI
S1
S2
CVSTDUM0R0
PC
VPM
2 1
4
5
0,3 Nm
CAREL E2 V/ E3V
unipolar valve
digital input to star
t
the regulation
24 Vdc
G
G0
20 VA
230 Vac
24 Vac
G
G0
3
Fig. 2.g
Key:
1
Ratiometric pressure transducer – evaporation pressure
2
NTC – suction temperature
3
Digital input to enable control
4
Personal computer for configuration
5
USB / tLAN converter
2.4 Installation
For installation, proceed as shown below, with reference to the wiring
diagrams and the technical specifications table:
1.
connect the probes: these can be installed up to a maximum
distance of 10 m from the driver; select the pressure probe suitable
for the refrigerant. For details on the recommended pressure probe
for each refrigerant, see “Commissioning”;
2.
connect any digital inputs, maximum length 10 m;
3.
connect the valve cable: it is recommended to use a maximum cable
length of 1 m for E2V and E3V valves.
4.
the 24 V models can be powered at:
•
24 Vac: use a class II safety transformer, adequately protected against
short-circuits and overload. Transformer power must be between
20 and 50 VA, as shown in the technical specifications table;
•
24 Vdc: use an external power supply, the see technical
specifications table;
5.
the connection cables must have a minimum cross-section of 0.35 mm
2
;
6.
power on the driver: the LED on the power supply/display comes
on and the driver will be immediately operational, with the default
parameters:
a. Refrigerant = R404A;
b. Type of control: multiplexed showcase/cold room;
c. Superheat set point = 11 K.
7.
program the driver, if necessary: see the “User interface” chapter;
8.
connect to the serial network where required. See the following diagrams
for connecting the earth on the 24 V EVD mini models.
EV
D
mini 24 Vac in serial network
Case 1:
multiple drivers connected in a network, inside the same electrical
panel, powered by the same transformer
GND
Tx/Rx+
Tx/Rx-
G
G0
DI
GND
Tx/Rx+
Tx/Rx-
G
G0
DI
230 Vac
24 Vac
pCO
PC
Fig. 2.h
Case 2:
multiple drivers connected in a network, inside different electrical
panels with the same earth point
GND
Tx/Rx+
Tx/Rx-
G
G0
DI
20 VA
230 Vac
24 Vac
GND
Tx/Rx+
Tx/Rx-
G
G0
DI
20 VA
230 Vac
24 Vac
pCO
PC
Fig. 2.i
Important:
Earthing of G0 and G in driver EVD mini 24 Vac
connected in serial network brings to permanent damage of the driver.
GND
Tx/Rx+
Tx/Rx-
G
G0
DI
20 VA
230 Vac
24 Vac
GND
Tx/Rx+
Tx/Rx-
G
G0
DI
20 VA
230 Vac
24 Vac
pCO
PC
NO!
Fig. 2.j
