Copeland E3 - Ahu; Analog and Digital Combiner; Anti-Sweat Control

©2025 Copeland LP.
026-1803 R13 Supervisor I&O User Guide 9 - 48
9.33 AHU
The AHU control application controls HVAC equipment,
rooftop units, or air handlers. The number of AHU applications
allowed is based on the total number of applications allowed
on the device. The AHU application provides basic
functionality to control a typical packaged HVAC unit. The
packaged HVAC units have up to four stages of heating and
cooling and may have a fresh air damper installed to allow
free-air cooling (economization) when conditions permit.
How To Add an AHU Device on the Supervisor:
1. From Home screen, click the Control Inventory icon.
2. From the Control Inventory screen, expand the desired
section (such as Refrigeration, HVAC, Lighting, and more)
to locate the Add Control drop-down list that contains the
application you wish to add. For AHU, expand the HVAC
category and click the Add Control drop-down list and
select AHU. Note that depending on the type of
application you are adding, different fields are required
and become editable (such as Protocol, Association, Port
ID, Address, and more).
3. Click the checkmark to save changes. To add multiple
instances quickly, click the Duplicate icon next to the
wrench.
4. To remove an application, click the box next to the
application name and click Delete Selected
Application(s) in the upper right corner of the screen.
Click OK or Cancel on the pop-up
window to proceed with the action or stop.
9.34 Analog and Digital Combiner
The Analog Combiner application is used for analog inputs.
Instead of using a single output source as an application
input, 16 input source combinations may be used. For
multiple inputs, a Multiple Input cell must be used. The
Multiple Input cell is a simple application that reads data
values from its inputs, combines them using a user-defined
combination strategy, and sends the combined value to the
desired application input. A common application for this is in
the HVAC control where a single heating control value comes
from the average number of temperature sensors throughout
the building. Two different types of Multiple Input cells may
be used if the inputs to be combined are analog or digital
sources.
Inputs:
In addition to the 16 analog inputs, combined Analog Input 1
to 16, these inputs is combined based upon the
CombMethod parameter setting. If they are not connected to
any of the Analog Inputs, the input value will not be used in
the calculation.
The user can connect a digital value to the Use Alt input to
select an alternate combiner method – as defined in the
AltCombMethod parameter. When the Use Alt input is true,
the combiner logic will use the AltCombMethod parameter to
calculate the combined value instead of the CombMethod
parameter.
The user can also provide a digital value to the InputSelect. If
this input is true, then the parameter InputSelect will indicate
which AnalogInputXX the user would like to set to the
combiner output value.
Outputs:
The Output value is the calculation of the combined analog
sensor inputs. The Alternate-Out value is always filled with the
calculated value as specified by the AltCombMethod
parameter. The ActiveInput value is set to a specific
value (1-16) and serves as the analog input value when the
CombMethdod is set to FIRST or SELECT.
9.35 Anti-Sweat Control
A case controller manages its anti-sweat heaters by
monitoring the dewpoint in and around the case area. The
dewpoint input value is compared to the anti-sweat
application’s control setpoints (the Full ON setpoint and the
Full OFF setpoint). Based on this comparison, the anti-sweat
heaters will do one of three things:
• If the input is equal to or above the Full ON
setpoint, the heaters remain ON 100% of the time.
• If the input value is equal to or below the Full OFF
setpoint, the heaters will be ON 0% of the time (fully OFF).
• If the input value is between the Full ON and Full OFF
setpoint, the heaters will be pulsed ON for a percentage
of the specified time interval. The
percentage is determined by proportionately
measuring where the dewpoint falls between the range
of values formed by the two setpoints.
Figure 9-22 shows an example of how anti-sweat control
works. The setpoints (Full ON dewpoint= 80°F, Full OFF
dewpoint = 20°F) form the range of dewpoints across which
the heaters will be pulsed. When the measured dewpoint is
45°F (directly in between both setpoints), the percentage will
be 50%, and the heaters will be pulsed ON for 5 seconds of
the defined 10-second interval. If the dewpoint drops to 30°F,