Emerson Site Supervisor, Руководство пользователя

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Site Supervisor Controller User Guide 2.0 026-1800 Rev 3 02-AUG-2016
To set up a setpoint reset for heating or cooling, the
user must specify the minimum and maximum range of
reset sensor values, and the maximum range of setpoint
adjustment.
As the value of the reset sensor varies within the mini-
mum and maximum range, an equivalent portion of the
maximum setpoint adjustment will be added or subtracted
from the heating or cooling setpoint. When the reset sen-
sor value is directly in between the minimum and maxi-
mum range values, nothing will be added or subtracted
from the setpoint. Between the halfway point and the min-
imum value, part of the setpoint adjustment will be sub-
tracted from the setpoint. Between the halfway point and
the maximum value, part of the setpoint adjustment will be
added to the setpoint. An example of this is shown in
Figure 5-13
.
5.23 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 Site
Supervisor:
1. From Home screen, navigate to Main Menu>
Summaries and Floor Plans> Site Summaries>
HVAC, click the screen drop-down arrow on the
upper right of the screen, click
Add Controls
.
2. Select the Control or Application Type -
AHU
,
enter the Quantity, Control Name and Serial
Type. Note that Serial Type information can be
enter later. Click
Save
to add the application.
3. A Confirmation box will appear saying that the
application is successfully added to the system,
click
Close
or
Edit these controls
.
4. The system will display the new application(s) on
the Site Summary screen.
5. Click the AHU application panel box to view the
application.
6. The system will display the AHU application
parameters.
7. The user can view and configure the properties of
the application by setting the Edit Mode to
ON
on the screen drop-down arrow on the upper right
of the screen.
5.24 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.
Figure 5-13
- Setpoint Reset Diagram
MIN
RANGE
MIDPOINT
MAX
RANGE
AD
D
SUBT
RA
CT
+0
RESET
SENSOR
RANGE
SET
POINT
CHANGE
MAX
CHANGE
MAX
CHANGE