EN - 40
17.1 Operating principle:
The master machine sends the following information to the slave machine:
- On/off.
- Heating/cooling mode
- Control temperature.
The master machine will not have access to detailed information about the slave machine (fault details, operation readings, unit parameters,
reading parameters, etc.) and vice versa.
If a BMS is used, each machine will have access to all the information on the other machine.
Important:
The master machine's BMS link manages information from the loop and the master machine. To obtain information on the slave
machine, its BMS link must be connected.
Loop description:
- The loop is limited to two units. Both may be assigned to the loop's operation or one may be assigned as a backup.
- The loop may be controlled in either heating or cooling mode. Switching between modes is managed in the same way as when a single
machine is running (no master/slave control).
- Each machine will be adjusted by its own software and the adjustments made to the master machine will control the units on the loop in cascade mode.
17.2 General:
In all cases, the slave machine's On/Off button can be used to cut the master machine's control over the slave machine.
Once a machine is configured as the master, it has control over the slave machine.
The machine with the most control stages must always be designated as the master machine.
The slave machine's control parameters become locked when P28 = Yes.
The time on the master machine's console is sent to the slave machine so that both have the same time.
If communication between the master and slave machine is lost for more than 10 minutes, the slave machine switches to independent operation
with its own information and displays the following message:
Automatic acknowledgment:
- The automatic operation controls are managed by each machine as if the machines were not linked.
- Load shedding via the on/off inputs is managed by each machine as if the machines were not linked.
- The pumps are also managed by each machine as if the machines were not linked.
Parameters P801 to P810 are hidden if P800 = No (i.e. on the slave machine.
17.3 Management of the functions:
►
Machine operation priority and operating time balancing:
- The order in which machines are started is determined based on faults and the number of hours of operation.
- A machine is available when it is off, has no faults, and is authorised to operated.
- The first machine to start is one that is available and has run for the shortest time.
Runtime balancing:
- After every 50 hours of machine operation, the system switches to the machine which has operated the least in order to balance the runtimes.
- While the system is on (and before it is shut off), the time counters of the machines that are running are compared and the order number is
changed so that the machine that has run the longest is shut off first.
- If a fault occurs on an active stage (or the stage is forced off), stage
n
becomes
n
–
1
.
- Stages are shut off in the reverse order that they were turned on regardless of their number of hours of operation.
The total runtime of each machine calculated by adding P285 and P286 on each machine.
►
B) Backup or auxiliary machine (P801 = Yes):
Without changeover:
The backup machine is designated by the customer (P803 = X).
Important:
In this configuration, the customer will have to run this machine twice a year to prevent the pump from seizing.
With changeover:
- The stopped machine with the longest running time is automatically set as the spare.
- If a partial fault occurs on a machine on the loop, that machine is automatically made the backup.
- If parameter P807
≠
0, the backup machine also serves as the auxiliary machine. It is started up if the temperature > se P807, and
stopped at 1 K below this value.
The backup machine may operate if:
- A machine has a link fault.
- A machine has a total fault.
- Operation of backup authorised if P807
≠
0 and the temperature
>
se P807.
On the backup machine the pumps are off, the LED flashes on and off at 1-second intervals and the following message is displayed:
►
Forced stop of machines:
This function can be configured to prevent a machine from operating.
►
Water loop winter protection:
If parameter P142 on the master machine = Yes
In heating mode:
- This function is possible if P142 on the master machine = Yes, if the automatic operation control inputs on both machines are open, and both
machines are set to On. The function must maintain the water inlet temperature on the heat exchanger at 30°C as soon as the outdoor
temperature
3°C (2 K differential = pump and compressors shut off immediately)(Cascade control on the return line).
- Adjust water-to-water units to the hot water sensor.
- The heating LED is lit; the On/Off LED flashes.
- If a fault occurs on the outdoor sensor, maintain the water loop at 30°C.
B O A R D L I N K F A U L T
M U L T I U N I T M A N A G E M E N T
M U L T I U N I T M A N A G E M E N T
B A C K U P M A C H I N E