Slave Mode - LU-VE Emeritus LU1W Manual De Usuario

MODBUS MODBUS
Parameter Name and
Register Register
Description
Base 0 Base 1
PR09
Time range for resource
percent variation in fast
0x0781 1922 response zone
PF21
0x07B7 1976 Start-up fans speed
PF22
0x07B8 1977 Start-up time
4.2.3

Slave mode

If the machine is slave (parameter PG01 = 1), the adjustment is proportional to the command received from the
remote master (0-10V, 4-20mA, analogue input AI2).
Attention: if the master signal is type 0-10V, depending on the hardware architecture of the remote master
controller, a voltage of more than 0V can occur on the AI2 input channel, even with a signal from the master = 0V. To
overcome this problem, a galvanic isolator must be interpolated between master controller and LU1W controller.
The adjustment of the various utilities (fans, adiabatic panels and spray) takes as a reference the remote master
control subdivision in 1, 2 or 3 areas based on the presence of wet resources and parameters P0R4 and PR05. The
division of the signal band between the different resources follows the same logic as the subdivision for the neutral
zone (paragraph 3.2.2). Therefore:
between 0% and PR04% of master signal → Ventilation control
•
between PR04% and PR05%/100% of the master signal → First/Single Wet Resource (Adiabatic or Spray)
•
between PR05% and 100% of master signal → Second Wet Resource Control (EMERITUS® spray + adiabatic
•
panels)
0V
4mA
VENTILATION
Attention: In SLAVE mode, the adjustment parameter PR02 remains a parameter of interest. Firstly, it represents
the "emergency" threshold beyond which it is reasonable to assume an anomaly of the master supervisor. In fact, if
the adjustment temperature exceeds the set-point for more than 60 seconds, the control is handled locally, with its
own probes. The set-point must then be set to the upper limit of the working amplitude for the remote supervisor
(e.g. set the PR02 to at least 55/60 °C for a condenser).
Correspondingly, even if the error status is detected on the incoming signal from the remote master (signal above or
below the standard signal limits), the LU1W controller manages the adjustment locally, on the base of the set-point
set and of the temperature/pressure acquired.
During local operation, the controller signals an alarm for the master failure (AL01) or for a master signal error (ES05,
see chapter 13 ALARMS) respectively. When the alarm condition returns, the controller returns to SLAVE mode.
LU1W - User Manual
Data Type and Notes
[sec]
- unsigned short int
[%]
- unsigned short int
[sec]
- unsigned short int
PR04%
1° Wet (AP or Spray)
Adjustment band Subdivision
39
Default
Min Max
value
5 1 9999
100.00 0.00 100.00
30 0 9999
PR05%
2° Wet (Spray + AP)
REV.1.1 – 07/11/2017 - ENG
MODBUS
Decimal
Register
positions
Type
0 holding
0.00 holding
0 holding
10V
20mA