Emerson PACSystems RX3i, User Manual

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RSTI-EP PROFINET I/O Controller User Manual Section 1
GFK-2571R May 2021
Introduction 27
PNSR
PROFINET System Redundancy: the PROFINET processes and mechanisms by
which an IO-Device is controlled by multiple IOCs in redundant PLCs.
RDO Record Data Object. Services used to read and write structured data stored
in a PROFINET IO-Device.
Reduction Ratio Along with Send Clock determines the Update Period for a PROFINET cyclic
data transfer between two devices (see IOCR). The Update Period equals the
Reduction Ratio multiplied by the Send Clock time. For example, if the
Reduction Ratio is 4 and the Send Clock is 1ms, the Update Period is 4ms.
Remote Node For an RX3i PROFINET network, a Remote Node is any PROFINET IO-Device,
such as a rack of I/O modules with a Remote Scanner or a third party
PROFINET IO-Device.
RIV Reference ID Variables
RTA Real-Time Acyclic. A PROFINET-IO Mechanism used to exchange non-
periodic data such as alarms.
RTC Real-Time Cyclic. A PROFINET-IO Mechanism used to exchange input and
output data.
Send Clock Value between 1 and 128 inclusive in units of 31.25 µs (equivalent to a range
of 31.25 µs to 4 ms) used to calculate the Update Period for a PROFINET cyclic
data transfer between two devices (see IOCR). The Send Clock is the basis for
all other scheduling parameters.
Send Offset The time to delay a scheduled PROFINET cyclic data transfer frame.
Measured in nanoseconds from 0 to 3,999,999. Must be less than the Send
Clock time.
SFP Small Form-factor Pluggable. Pluggable, hot-swappable transceivers.
SNMP
Simple Network Management Protocol. UDP-based network protocol that
facilitates the exchange of management information between network
devices.
Status Bits Module status data in RX3i CPU reference memory.
Submodule PROFINET-IO representation of the smallest configurable entity of a
PROFINET Module.
SVC_REQ Service Request Function Block. A control system service initiated by the
RX3i CPU.
TLV Type-Length-Value
Unicast In Ethernet, the transmission of a network message to an individual host.
Update Period The time between PROFINET cyclic data transfers between an IO-Controller
and an IO-Device.
USB Universal Serial Bus
WinLoader A software utility used to download and install firmware upgrades via a serial
port.