Carel EVD Evolution Twin, Руководство пользователя

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ENG
“EVD Evolution TWIN” +0300006EN - rel. 2.6 - 31.01.2019 23
The activation status of the procedure is indicated on the standard display by
the message “TUN” at the top right.
Superheating
4.9 K
Valve opening
44 %
TUN
-- Relais
A/B
Fig. 5.e
The optimisation procedure can only be performed if the driver is in control
status, and lasts from 10 to 40 minutes, performing specific movements of the
valve and measurements of the control variables.
Note:
•
during the function maintenance of the superheat set point is not
guaranteed, however the safety of the unit is ensured through activation of
the protectors. If these are activated, the procedure is interrupted;
•
if, due to external disturbance or in the case of particularly unstable
systems, the procedure cannot suitably optimise the parameters, the
controller will continue using the parameters saved in the memory before
the procedure was started. If the procedure ends successfully, the resulting
control parameters will be automatically saved.
•
both the tuning procedure and adaptive control can only be enabled for
superheat control, they cannot be used for the special control functions
For CAREL internal use only, some tuning procedure control parameters
can be shown on the display, supervisor, pCO and VPM; these must not be
modified by non-expert users.
These are:
-
Tuning method
-
Adaptive control status
-
Last tuning result
Parameter/Description Def. Min. Max. UOM
SPECIAL
Tuning method
0 0 255 -
Tab. 5.f
Tuning method is visible as a parameter in the Special category, the two other
parameters are visible in display mode. See paragraph 3.4.
Note: the “Tuning method” parameter is for use by qualified CAREL
technical personnel only and must not be modified.
5.4 Control with Emerson Climate Digital
Scroll ™ compressor
Important: this type of control is incompatible with adaptive control
and autotuning.
Digital Scroll compressors allow wide modulation of cooling capacity by
using a solenoid valve to active a patented refrigerant bypass mechanism.
This operation nonetheless causes swings in the pressure of the unit, which
may be amplified by normal control of the expansion valve, leading to
malfunctions. Dedicated control ensures greater stability and efficiency of the
entire unit by controlling the valve and limiting swings based on the instant
compressor modulation status. To be able to use this mode, the LAN version
driver must be connected to a Carel pCO series controller running a special
application to manage units with Digital scroll compressors.
Parameter/Description Def.
CONFIGURATION
Main control
multiplexed showcase/cold
room
...
air-conditioner/chiller with Digital Scroll
compressor
Tab. 5.g
S2 S1
EVD evolution
twin
S
F
L
CP
C
S3 S4
E2
E1
V
M
EEVA
EEVB
PB TB
PA TA
Tx/Rx
GND
shield
pCO
GND
Fig. 5.f
Key:
CP Compressor V Solenoid valve
C Condenser S Liquid gauge
L Liquid receiver EEV Electronic expansion valve
F Dewatering filter E1, E2 Evaporator
TA, TB Temperature probes PA, PB Pressure probes
For information on the wiring see paragraph “General connection diagram”.
5.5 Special control
E PR back pressure
This type of control can be used in applications in which a constant pressure
is required in the refrigerant circuit. For example, a refrigeration system may
include different showcases that operate at different temperatures (showcases
for frozen foods, meat or dairy). The different temperatures of the circuits are
achieved using pressure regulators installed in series with each circuit. The
special EPR function (Evaporator Pressure Regulator) is used to set a pressure
set point and the PID control parameters required to achieve this.
PA
E1
V1 V2
EVA
M T
PB
E2
V1 V2
EVB
M T
S1
EVD evolution
twin
S3
Fig. 5.g
Key:
V1 Solenoid valve E1, E2 Evaporator 1, 2
V2 Thermostatic expansion valve EVA,
EVB
Electronic valve A, B
PA,
PB Pressure probe driver A, B
For the wiring, see paragraph “General connection diagram”.