FP AHU Configuration

This section covers how to view and edit the settings of a typical FP AHU.

To view and edit an existing FP AHU's settings, click the FP AHU icon on the Floorplan, in the Temperature Layer.

The FP AHU Control Screen will appear.

FP AHU Status And Reference Temp

The FP AHU's current operating status is shown in the AHU Status field in the top-left corner of the diagram. For a list of all possible statuses, see FP AHU Control Status.

The FP AHU's current reference temperature is shown in the AHU Reference Temp field in the top-left corner of the diagram. This value is set by the active Temperature Mode.

Alarms

The alarms shown on the Control Screen are as follows:

Damper Alarm	if the unit is in free cooling and the Supply Air is 10° above Outside Air then the damper may not be open or faulty
DX Minor	if the unit is in DX cooling and the Supply Air is 5–10° below Return Air then DX may not be working properly
DX Major	if the unit is in DX Cooling and the Supply Air is less than 5° below the Return Air then DX is not working properly
Smoke Detect	If the Smoke Detection digital input is high then an alarm is highlighted and the unit will be in Smoke Detection mode

Editing Control Points

To edit any control points, click the Edit Points button, adjust the dropdown selections accordingly, and then click Save. More information …

FP AHU Info Panel And Advanced Panel

The FP AHU Info Panel and Advanced Panel are used to manage the FP AHU setup. The Info Panel is found in the bottom-left corner. The Advanced Panel is accessed via the Advanced button at the bottom of the Info Panel (moderator password required). The Advanced Panel contains all of the settings available in the Info Panel plus some further settings.

The settings of the Advanced Panel are as follows:

FP AHU Control Settings
Description	Description of the FP AHU Object
Asset Name	Unique customer reference number for the FP AHU
Temp Mode	One of 4 Configurable Modes (and 1 fail-safe mode that is not configurable) of control regarding which temperature sensor(s) thewill control against in certain situations. The system may change to a different temperature mode if the choice configured by the user is not achievable. For more information, seeTemperature Modes.
Cooling Setpoint	The cooling will enable when the reference temp is above this setpoint
Hysteresis	How many degrees the temperature has to drop below setpoint to disable cooling
Fan Hi-Speed Setpoint	The temperature at which the system will allow the FP AHU fan to operate at full speed.
Hysteresis	Once the strategy has enabled the fan to run at full speed it will not switch it off until the temperature has fallen below the Fan Hi-Speed Setpoint value minus this hysteresis value, e.g. if Fan Hi-Speed Setpoint = 24°C and Hysteresis = 1°, the fan will disable at 22.9°C.
AHU Enable Setpoint	The FP AHU will enable when the reference temperature is above this setpoint
Hysteresis	How many degrees the temperature has to drop below setpoint to disable the FP AHU
Min Outside Air	If the WEMS outside air temperature is below this setpoint then WEMS disable the DX Inhibit and the FP AHU controls to its own settings
Max Outside Air	If the WEMS outside air temperature is above this setpoint then WEMS disable the DX Inhibit and the FP AHU controls to its own settings
Max Ref Temp	If the WEMS reference temp temperature is above this then WEMS disable the DX Inhibit and the FP AHU controls to its own settings
Test Mode Time	The length of time for which Test Mode is active
Smoke Run On Time	If Smoke Detect Alarm is active and then clears, this is the number of minutes it will run on the fan before going back to normal settings
AHU Stage	Four pre-defined default AHU Enable and Cooling Setpoints for the unit. Stage 1 has the lowest setpoints and Stage 4 has the highest
FP AHU Alarm Settings
Alarming	Enable or disable alarms
Damper: Wait Time	If damper alarm setpoints have been breached, this is the amount of minutes it will wait before it sends the alarm
Damper: Differential	The number of degrees that the Supply Air Temp is above the Outside Air Temp before a damper alarm is generated
Damper: Diff Hysteresis	The number of degrees that the Supply Air Temp must be under the differential for the alarm to clear
DX Major/DX Minor: Wait Time	If DX alarm setpoints have been breached, this is the amount of minutes it will wait before it sends the alarm
DX Major: Differential	If the difference between Supply Air Temp and Return Air Temp is below this setpoint then an alarm is generated
DX Major: Diff Hysteresis	The number of degrees that the Return Air Temp must be above the differential for the alarm to clear
DX Minor: Differential	If the difference between Supply Air Temp and Return Air Temp is below this setpoint then an alarm is generated
DX Minor: Diff Hysteresis	The number of degrees that the Return Air Temp must be above the differential for the alarm to clear

Manual Override

The Manual Override button at the top of the screen is used to put the unit back into fail-safe mode. This stops all control by the system over the FP AHU and reverts it back to its normal control strategy, as if the WEMS equipment were not there.

Test Mode

When the Manual Override button is pressed, another button labelled Test Mode appears at the top of the screen. This button allows engineers the ability to test the relay digital outputs to see whether they are wired and operating correctly. This is a useful test to conduct when commissioning the unit and helps to highlight any wiring issues or faults with the physical units themselves.