Rockwell Automation 2711 Standard PanelView Operator Terminal User Manual - Manual (Page 278)

278 Publication 2711-UM014G-EN-P - September 2008
Glossary
remote I/O link
A serial link for carrying I/O data between a PLC or SLC
processor/scanner and remote I/O adapters.
repeater
Two-port component that receives and transmits all data from one
segment to another.
restore
To load an application from a memory (PC) card.
RS-232
An EIA standard that specifies electrical, mechanical, and functional
characteristics for serial binary communication circuits in a
point-to-point link.
RS-485
An EIA standard that specifies electrical characteristics of
balanced-voltage digital interface circuits in a multi-point link.
scheduled messages
Messages that occur at a regular specified interval. They are assigned a
particular portion of the network update time (NUT) and are always
transmitted at that time.
safety extra-low voltage (SELV)
A voltage that, under all operating conditions does not exceed 42.4 V
peak or dc between conductors, or between any conductor and earth,
in a circuit that is isolated from the main power supply by means of a
safety isolating transformer or an equivalent means. National
regulations have to be considered for a correct isolation voltage rating.
scratchpad
A window that appears in the center of the terminal display that
allows data entry by using the terminal or screen keypad.
screen
1) the viewing surface on which data is displayed. 2) The visual image
on a screen.