Rockwell Automation Allen-Bradley AADvance T9110, Руководство по решениям

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Rockwell Automation Publication ICSTT-RM447M-EN-P - July 2019 129
Module Overview and Specifications Chapter 7
T9451 Digital Output
Module, 24Vdc, 8 channel The T9451 digital output module has 8 channels for a maximum of 8 field
elements and can switch 1 A at 32 Vdc for each device. It features voltage and
load current monitoring on each channel, reverse current protection and short
and open circuit line monitoring. It is designed to always be able to switch off
an output when demanded. No single failure in the module can cause a stuck-
on failure. The module supports dual redundant power feeds for field devices
without the need for external diodes.
The output module isolates the processor module from the output channel
control and data management circuits, thus protecting the processor module
from possible faults in the output control circuits and field connections. An
output channel protection activates when the channel load exceeds a safe limit.
And, a reverse voltage protection circuit in each output channel verifies that
externally applied voltages do not supply current flow into the module outputs.
The module has self-checking functionality. Short circuit and open circuit line
monitoring is supplied on all outputs (
see article 605753 on the Rockwell
Knowledgebase website)
. Internal diagnostics do ongoing functionality checks
ensuring that the output channel command data is correctly transferred to the
output. The processor module initiates a test sequence on each output channel,
checking for 'stuck-on' and 'stuck-off ' conditions on the output switch pairs.
Front panel LEDs give module, channel and field connection status
indications. These status indications can also be connected to application
variables and viewed at the Workbench.
When a controller uses a pair of digital output modules in a dual configuration,
the two fail-safe output switches on each channel are combined in a parallel
arrangement so that they automatically form a fault-tolerant output
configuration.
The AADvance Workbench has settings for individual digital output channels:
• You can specify a shutdown state for an output channel that defines how
the output will behave when the module is in a shutdown mode.
• You can disable the line test feature for an output that disables detection
of a no-load condition (e.g. for used output channels).
Channel load (135 ± 0.2 %)
Ω
Channel isolation:
T9831 None
T9832/T9833 ± 1.5 kVdc Maximum withstanding for 1 minute
Maximum field loop power dissipation 0.08 W for each field loop (0.27 BTU/hr)
Attribute Value