Control With Siam Anb Scroll Compressor; Superheat Regulation With 2 Temperature Probes - Carel EVD evolution User Manual

Key:
CP Compressor
C Condenser
L Liquid receiver
F Dewatering fi lter
S Liquid gauge
For information on the wiring see paragraph 2.11 "General connection
diagram".
5.5 Control with SIAM ANB scroll
compressor
Important: this type of control is incompatible with adaptive
control and autotuning.
To be able to use this control function, only available for CAREL valve
drivers, the driver must be connected to a CAREL pCO programmable
controller running an application able to manage a unit with SIAM ANB
scroll compressor. In addition, the compressor must be controlled by the
CAREL Power+ "speed drive" (with inverter), specially designed to manage
the speed profi le required by the compressor operating specifi cations.
Two probes are needed for superheat control (PA, TA) plus two probes
located downstream of the compressor (PB, TB) for discharge superheat
and discharge temperature (TB) control.
Parameter/Description
CONFIGURATION
Main control
...
AC/chiller with SIAM ANB compressor
C
L
F
S
M
V
E
EV
Fig. 5.c
Key:
CP Compressor V
C Condenser S
L Liquid receiver EV
F Dewatering fi lter E
TA, TB Temperature probes PA, PB
For information on the wiring see paragraph 2.11 "General connection
diagram".
To optimise performance of the refrigerant circuit, compressor operation
must always be inside a specifi c area, called the envelope, defi ned by the
compressor manufacturer.
V Solenoid valve
V2 Thermostatic expansion valve
EV Electronic valve
E Evaporator
P Pressure probe
Def.
multiplexed showcase/cold
room
Tab. 5.i
TB
PB
POWER +
speed drive
EVD
evolution
0V +
1
CP
GND Tx/Rx
Modbus®
RS485
PA TA
pCO
shield
Solenoid valve
Liquid gauge
Electronic valve
Evaporator
Pressure probes
The pCO controller defi nes the current set point according to the point of
operation within the envelope:
•
superheat setpoint;
•
discharge superheat setpoint;
•
discharge temperature setpoint.
Parameter/Description
ADVANCED
Superheat setpoint
Discharge superheat setpoint
Discharge temperature setpoint
Note:
•
this control function is only available CAREL valve drivers.
•
no set point needs to be confi gured by the user.
5.6 Superheat regulation with 2
temperature probes
-
2 3
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
CONFIGURATION
Main control
...
superheat regulation with 2 temperature
probes
21
Inviluppo ⁄ Envelope
Temperatura di evaporazione (C°)
Evaporation temperature (C°)
Fig. 5.d
Def. Min. Max.
11 LowSH: 180 (324) K (°F)
threshold
35 -40 (-72) 180 (324) K (°F)
105 -60 (-76) 200 (392) °C (°F)
Def.
multiplexed showcase/cold
room
"EVD evolution" +0300005EN - rel. 3.1 - 25.07.2011
ENG
UOM
Tab. 5.j
Tab. 5.k