Rockwell Automation 1764-xxxx MICROLOGIX 1500 PROGRAMMABLE CONTROLLERS - Manual (Page 162)

Publication 1764-UM001B-EN-P - April 2002
Glossary 6
modem
Modulator/demodulator. Equipment that connects data terminal
equipment to a communication line.
modes
Selected methods of operation. Example: run, test, or program.
negative logic
The use of binary logic in such a way that “0” represents the desired
voltage level.
network
A series of stations (nodes) connected by some type of
communication medium. A network may be made up of a single link
or multiple links.
nominal input current
The typical amount of current seen at nominal input voltage.
normally closed
Contacts on a relay or switch that are closed when the relay is
de-energized or deactivated. They are open when the relay is
energized or the switch is activated.
normally open
Contacts on a relay or switch that are open when the relay is
de-energized or the switch is deactivated. They are closed when the
relay is energized or the switch is activated.
off-delay time
The OFF delay time is a measure of the time required for the
controller logic to recognize that a signal has been removed from the
input terminal of the controller. The time is determined by circuit
component delays and by any applied filter.
offline
When a device is not scanning/controlling or when a programming
device is not communicating with the controller.