Rockwell Automation 2755 Enhanced Decoder Series B - Manual (Page 347)

Glossary G–6
Publication 2755-833
multi-drop link
A link that has more than 2 stations (contrasted with a point-to-point
link.)
multiplexer
The incorporation of 2 or more signals into a single wave from
which the individual signal can be recovered.
N
NAK
See negative acknowledgement.
Negative Acknowledgment
An ASCII control character transmitted by a receiver as a negative
response to the sender.
NEMA standards
Consensus standards for electrical equipment by the members of the
National Electrical Manufacturers Association (NEMA).
NEMA Type 1
Enclosure intended for indoor use. Provides a degree of protection
against contact with the enclosed equipment in locations where
unusual service conditions do
not exist. The enclosure is sheet steel, treated to resist corrosion.
NEMA Type 4
Enclosure intended for indoor or outdoor use primarily to provide a
degree of protection against windblown dust and rain, splashing
water, and hose directed water; and to be undamaged by the
formation of ice on the enclosure.
No-Match
An output condition in which decoded data does not match an
entry in the match code table.
No-Read
An output condition in which bar codes on a package are not read
correctly or are incomplete (fields per package count not satisfied).
numeric
A character set that includes only the numbers as contrasted to
alphanumeric which includes both letters and numerals.
O
orientation
The alignment of bars and spaces the the scanner. Often referred to
as vertical (picket fence) or horizontal (ladder).