Rockwell Automation 1760-DNET Pico DeviceNet Communications Module User Manual - Manual (Page 160)

Publication 1760-UM003A-EN-P - September 2005
Glossary 8
Polled I/O connection
A polled I/O connection is used to establish a conventional
master/slave relation between a programmable controller and a
DeviceNet device, and represents a PtP connection between two
stations on the fieldbus. The master (client) transmits a polling request
to the slave (server), and this answers with a polling response.
• 3 bytes of output data
S1 to S8
Pico/GFX output range, RUN/STOP
(inputs at the DeviceNet master)
• 3 bytes of input data
R1 to R16
Pico/GFX input range, RUN/STOP (outputs of the DeviceNet
master)
Equipotential bonding
Adaptation of the electrical level of the body of electrical equipment
and auxiliary conductive bodies by means of an electrical connection.
Potential-free
Galvanic isolation between the reference potentials of the control and
load circuit of I/O modules.
Common potential
Electrical interconnection of the reference potentials of the control
and load circuit of I/O modules.
Response time
In a bus system this represents the time interval between the
transmission of a read request and receiving the answer. Within an
input module, it represents the time interval between the signal
change at an input and its output to the bus system.
Repeater
Amplifier for signals transferred across a bus.
Screen
Term that describes the conductive covering of cables, cubicles and
cabinets.