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21. 07. 20. Document Number 671954
Nuaire |
Western Industrial Estate
|
Caerphilly
|
CF83 1NA
|
nuaire.co.uk
XBC+ with Ecosmart Connect (C) Control
Installation Manual
6.8 Trickle Mode
When trickle mode is active, the fans will run at their minimum speed
even when there is no enable signal. Heating and cooling will also
function in this mode if available. While in trickle mode, the unit will
function in “Supply Temperature Control Mode” but with a different,
wider deadband, set by the network input Trickle Deadband.
6.9 Frost Protection
Should the internal temperature of the unit fall below a value defined
in the commissioning variables, the control will override all heating/
cooling logic to open the LPHW or CW control valves, if fitted. This is
to allow any protective flow through the heating/cooling coils. The
supply fan will also stop and the appropriate frost protection software
module will enter an alarm state. This period will last for a minimum
of 5 minutes by default. The fault relay will also open. Heat and cool
demand relays will operate and the software frost alarm will enter an
alarm state. Frost protection will only function if the Heating Type or
CoolingType setpoints are set to LPHW or CW.
6.10 Summer Night Free Cooling
Once enabled in software, this routine uses an individual time schedule
to cool the fabric of the building at night using only the external air.
This mode only functions if the daytime temperature is above the
setpoint, cooling is possible and if the cooling air is not too cold.
6.11 Purge Mode
Once enabled in software, this routine uses an individual time schedule
to provide a period of increased air change throughout a space. This
mode only functions if the inlet air is above a minimum temperature
of 12°C. While purge is in progress, the unit will function in “Supply
Temperature Control Mode” but with a different, wider deadband, set
by the network input “Trickle Deadband”.
6.12 Hibernate
This mode is available for LPHW and CW units where the valves are
required to be driven open in anticipation of a period where the unit is
electrically isolated and inactive. When enabled via the network input
“Hibernate Mode” this will stop the fans and open all LPHW & CW
valves fully. The unit can then be powered down. This mode activation
is reset upon power cycle so when restarted the unit will function as
normal.
This mode is for periods when to building is left dormant and will stop
the coils trapping water and causing a freeze risk. It will be the buildings
responsibility to provide freeze-preventative heating during this time.
This can also be used for a cleaning or flushing cycle.
6.13 Alarms
6.13.1 Critical Alarm (Latching)
Once in critical alarm state the unit will drive all heating and cooling
outputs to 0V. In the event of fan fail other functions continue as
normal. The critical alarm is latched and requires power cycle or reset
via the “Reset Alarms” variable.
Causes of critical alarm:
•
Fan fail via fault circuit 1
•
Heater overtemp via fault circuit 1
6.13.2 Maintenance Alarm (Non-Latching)
Once in maintenance alarm state the only action taken is de-energising
of the fault relay. Once the trigger is removed, the alarm will reset
automatically.
Causes of maintenance alarm:
•
Sensor Failure
•
Low supply temperature, default 8°C. This can be set to stop fans
if required
•
Frost protection routine active, default 4°C (This only runs if water
valves are selected as fitted
•
Excessively high supply temperature reading (This will stop
heating)
•
Filter dP fault (if fitted)
All alarms have a hold off period set by the setpoint “Alarm Delay”.
Maintenance alarms are not covered by warranty.
6.13.3 Thermal Trip Alarm (latching)
In case of software failure, as a final resort, the electric heater is
protected by a fail-safe thermal overload switch. This switch disables
the heater controller via a contactor once the temperature reaches
80°C. When this occurs, the critical alarm will latch in software and the
supply contactor will latch in the off position. Once the unit cools, the
contactor will remain latched off until power cycle.
6.13.4 Configurable Analogue Output (OUT4)
OUT4 is a configurable analogue output which can be set to the
following functions via the multi-state object “OUT4 Mode”.
•
Cooling Demand (Default Setting)
This will provide a standard 0-10V cooling output. This output will only
function if a cooling type is selected.
•
ES Classic BMS
This option will provide a 0-10v ESClassic BMS output based on
ventilation demand. This can then be used in conjunction with the fan
run relay to run multiple slave Classic units from a master Connect
control.
The type of BMS output can be selected by the multi-state object ‘ECS
BMS Thermic Output’.
Auto
- The BMS output will switch between heating and cooling
depending on outdoor air temperature.
None
- The unit will only supply ‘Vent Only’ voltages
Heating
- The unit will only supply ‘Heating’ voltages
Cooling
- The unit will only supply ‘Cooling’ voltages
6.13.5 Fire Alarm
Once the Fire Alarm object is switched to the Alarm State, all fans,
heating and cooling elements will stop instantly. The fault relay
will de-energise and a fault message will be sent to the ESCO-LCD.
Once the fire alarm status is released, the units will continue running
automatically.
6.13.6 ES Classic BMS Output Table
Vent Only
Cooling
Heating
OFF / TRICKLE
0.25V
-
-
SPEED 1
0.5V
0.75V
1V
SPEED 2
1.5V
1.75V
2V
SPEED 3
2.5V
2.75V
3V
SPEED 4
3.5V
3.75V
4V
SPEED 5
4.5V
4.75V
5V
SPEED 6
5.5V
5.75V
6V
SPEED 7
6.5V
6.75V
7V
SPEED 8
7.5V
7.75V
8V
SPEED 9
8.5V
8.75V
9V
SPEED 10
9.5V
9.75V
10V
