NuAire B815H/ER/AT-L, Инструкция по установке, эксплуатации и обслуживанию

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BOXER BPS ECOSMART ADAPT (TREND) CONTROL (AT)
7.0 DESCRIPTION OF CONTROL - SOFTWARE STRATEGY
A comprehensive unit
control specification -
factory fitted and tested
to provide guaranteed
operation from a
single supplier – one who
will take responsibility.
7.1 GENERAL
The system incorporates a web enabled Trend iQ4E/96/LAN/BAC/230
controller with iQ4/IO/8DO relay expansion module.
7.2 UNIT CONTAINS THE FOLLOWING CONTROLLABLE ITEMS:
7.3 ENABLE SIGNAL
• Supply fan.
• Extract fan.
• Heat recovery bypass damper (If applicable).
• Thermal wheel (if applicable).
• Heating coil (if fitted).
• Cooling coil (if fitted).
• DX coil (if fitted).
• Inlet damper (if fitted).
• Exhaust Damper (if fitted).
• Recirculation damper (if fitted).
The unit can be enabled via the following methods:
• Software switch (ENABLE) via SDU, IQView4, IQView8 or network.
• Switched live (230VAC) input, PIR etc.
• Extra Low voltage contacts.
• Night cooling / summer free-cooling strategy.
• Scheduled via weekly calendar.
When the enable signal is removed, the unit will run on for a time defined by the
run-on setpoint. If an electric heater is fitted, the fans will automatically run-on
for an extra 2 minutes, without heating, in order to dissipate residual heat.
For DX units the fans will run-on for an extra 5 minutes, this is to allow for the
ramp down of the reverse cycle compressor.
7.4 OCCUPANCY CONTROL
7.5 BOOST
7.10 INLET / OUTLET (OPTIONAL)
7.7 PRESSURE SENSOR
7.8 FILTER DP SWITCH
7.9 THERMAL WHEEL / PLATE HEAT EXCHANGER BYPASS
7.6 TRICKLE MODE
When a Trend occupancy sensor is selected via UI4 & 5 software module, the
control will look for a Trend OCC-U sensor in the appropriate input.
An occupied signal will give an enable signal.
0V = Occupied
14V = Unoccupied
When the control receives a boost signal the fans will run at boost speed. Once
the signal is removed the fans will run on for a time defined by the boost run-on
setpoint.
Inlet and outlet dampers are 24vac and controlled by the iQ4-8DO relay 7.
When energised it gives a 24vac signal to both I/O dampers to open.
When installed, there is the option of connecting the internal damper close
switch to the fault circuit alarm circuit 2 (orange wires).
When IO dampers are fitted the strategy Switch “IO Damper Fitted” must be set
to “On”. This will cause the software to delay the fans starting for the IO Damper
delay period. It will also ignore faults on Alarm Circuit 2 if the fans are stopped
and the dampers are closed intentionally.
See Internal connection section for physical damper connections.
An extract air pressure sensor is fitted as standard. This is disabled in the Trend
strategy by default but can be enabled by the software switch “Enable Constant
Pressure”.
When enabled, the unit will increase the fans speeds as required until the
pressure differential between the extract air and atmosphere reaches the
constant pressure setpoint. The pressure sensor is a 0-10v 0-1000Pa sensor on
the iQ4E input 6.
3 filter differential pressure switches are fitted as standard. These monitor the
Extract filter, and Supply filter and Supply pre-filters.
These are connected in series with Alarm Circuit 2 (orange wires) and will break
the circuit on overpressure. The adjustable range is 0.5 to 4 mbar and is set by
default to 2mbar.
The plate heat exchanger bypass damper and thermal wheel both run on the
same iQ4-8DO Relay 1. Energised = Bypass.
The bypass strategy is as follows.
If the fresh air temperature is equal to the setpoint within the deadband, then
the heat exchanger will be forced into bypass mode.
The 24vac bypass signal from the Trend relay is converted by relay logic for each
of the following options:
• Thermal Wheel
Runs on a volt free enable signal, which is produced using a combination
of the HX bypass relay and fan run relay to close the circuit if fans are
running and the unit is not in bypass.
• Plate Heat Exchanger
The HX bypass damper opens on a 24 Vac signal which is produce from the
bypass damper relay.
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.