User manual

Characteristics of the XBT Terminal Range
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Polling Times
Overview
The polling times for non-connected equipment differ between XBT N/R/RT
terminals and XBT NU400 terminals. The following sections describe general polling
times of XBT N/R/RT terminals and specific polling times of XBT NU400 terminals.
General Polling Time for Non-Connected Equipment
The XBT N/R/RT terminal polls the missing equipment (usually a PLC) every 5
seconds. All the configured PLCs in an application should be connected. A missing
equipment is therefore considered to be a temporary problem, i.e. the PLC or XBT
is temporarily disconnected, and communication will resume as soon as the
connection is re-established. In this arrangement, degraded communication
performance is considered acceptable.