GE RX3i PROFINET User Manual page 24

Glossary, continued
PNC
PROFINET Controller. This could be a separate module, e.g. IC695PNC001 for the RX3i family, or a functional
component of a product such as the PROFINET controller embedded in the ICRXICTL000, IC695CPE330, or
IC695CPE400. Refer to Section 1.4.1.
PNS
PROFINET Scanner. Refer to Section 1.4.2.
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.
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.
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.
WinLoader
A software utility used to download and install firmware upgrades.
GFK-2737F December 2016
Chapter 1. Introduction
17