Specifications

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1.3.3 LCD Touch Screen Display
The objective of the LCD touch screen display is to provide the user an intuitive,
easy to manipulate means of controlling the system. The display should be large
in size so that it is easy to see when mounted on a wall. The buttons should be
of ample size so that they are easily manipulated with a normal sized finger. The
display should be color, and look professional. It should be regularly updated
with the current temperature and relative humidity inside the building so the user
is aware of the current inside conditions. The touch display must be graphically
advanced so it is pleasing to look at. The LCD touch screen display is likely the
only part of the system the user will ever see or interact with and therefore
appearance and functionality is of utmost importance when developing the LCD
touch screen display. The LCD touch screen display is to be fully operated by
any person, and require no training or previous touch screen experience by the
user.
1.4 Specifications and Requirements
1.4.1 Detailed Specifications
The following specifications are derived from several meetings with our sponsor,
AC3 Development Group, LLC. Although these values are estimates, careful
consideration has gone into developing realistic specifications necessary for the
design of a practical HVAC control system. These are only initial estimates of
what is necessary and will most likely change as problems arise, however we are
going to try to stick to these initial values as much as possible as they are what
we have determined to be ideal for this system.
 Total cost of $1500 or less for initial prototype
 Wireless transmission of temperature and relative humidity data
over a distance of at least 100 feet
 Ability to connect to a web server to allow for remote control of
main control unit via mobile device
 Must be able to provide 24V AC to control HVAC components
 Must be able to measure realistic outdoor temperature (0 ˚F – 110
˚F) and relative humidity (0% - 100%) values for all climates
 Must be able to measure indoor temperature (+- 0.5 ˚C) and
relative humidity (+- 5%) with specific accuracy
1.4.2 Detailed Requirements
The requirements for our project have been provided by our sponsor, AC3
Development Group, LLC. Our system is required to sense temperature and
relative humidity from inside and outside a building (residential or commercial),
read the settings determined by the user, and make an intelligent decision to
satisfy the preset temperature and relative humidity levels in the most effective
and energy efficient manner.