#1 Character size – How can I be sure people can read it?
The most important selection criteria is deciding where the
display will be placed and estimating the typical and maximum viewing distance. This will decide how large the text needs to be for
optimum legibility.
The typical "rule of thumb" is 1" of character height for every
50 feet of maximum viewing distance. Therefore, a standard 2" character can be read from 100 feet away and a 4" character can
be read from 200 feet away.
Let’s make it easier yet:
• In most applications, a 1.5" to 2" character will meet your
needs.
• In large warehouses or production areas, 3" to 4" characters
are typically required.
• An outdoor environment is a little different story…most static letter
boards you see use 4" or 6" letters, while most road side signs use about 10" characters (as a point of reference, signs next to an
interstate will usually start with at least 36" to 48" characters).
#2 Display size – How big of a display do I really need?
The second most important selection criteria is determining how
much data needs to be shown at one time. LED displays can cycle through long messages and stream data automatically, but
the viewer may need to wait to see the information that is most relevant. Of course, LED displays can be built to nearly any
size, but the bigger they are, the more expensive they get. It is important to optimize your investment while insuring that the
most important data is always on the display for quick viewing.
#3 Data source – Where is the information coming from?
Alpha displays offer a broad variety of communications
interfaces that will plug into your existing systems, without costing a fortune in integration services.
Windows Applications and TCP/IP Network Communications
LED displays are the most effective when the information on them
is current. Most Windows® applications on the market today can easily share data on your network. That same technology is
used to get it to your displays.
Alarms and Process Control Applications and Direct RS232/RS485
Communications
Imagine the improved efficiency by adding real information to
your alarms, in addition to the horns, buzzers, stack lights and strobes. Process information can be continuously displayed, so
action can be taken before the alarm condition is reached.
