Manual

SDS-8402
Trusted
TM
Industrial Control System
Trusted
TM
Dual 24Vdc Digital Input Module-T8402
Issue 5 Jan 2006
FRONT PANEL
DESCRIPTION
The Trusted
TM
Dual 24V dc Digital
Input Module interfaces to 60 field
input devices. A wide input voltage
range and programmable thresholds
allow the module to be used in
current source and current sink
configurations. Comprehensive
diagnostic tests are performed on
each input channel, including tests for
stuck on and stuck off failures. Fault
tolerance is achieved through Dual
Redundancy within the same module
for each of the 60 input channels.
When a line-monitoring device is
installed at the field switch, the
module can detect open and shorted
field cables. Line monitoring can be
independently configured for each
input channel.
The module provides on-board
Sequence of Events (SOE) reporting
with a resolution of 1ms. A change of
state triggers an SOE entry. States
are determined by programmable
voltage thresholds that can be
configured on a per channel basis.
When the field voltage and field return
are connected to the auxiliary input
channels of the module, thresholds
can be specified as a ratio of the
current field supply voltage.
Each section of the module, referred
to as a slice, conditions and
measures each channel
independently. Each slice is opto-
isolated up to 2500V dc. Each slice
sends its data to a safety layer
hardware voter that presents the
information from both slices to the
Trusted
TM
TMR Processor. When a
fault is detected on any dual input
channel, the Trusted
TM
TMR
Processor will flag the error,
indicating the need to replace the
module. The Trusted
TM
TMR
Processor will continue to use the
information provided by the remaining
slice until a replacement module is
available. Replacement modules can
be located in a standby slot next to
the module or in a designated
SmartSlot with a temporary
connection to the same Trusted
TM
Termination Assembly.
Modules may be placed in any I/O
module slot in a Trusted
TM
Processor
Chassis or Expander Chassis. Once
the I/O module configuration is set,
mechanical keying is available on all
I/O modules to prevent inserting a
module into an incorrect slot.
Configuration of the module is carried
out using the Trusted
TM
Toolset
running on an Engineering
Workstation. Once configured and
loaded into the Trusted
TM
Controller,
replacement modules are on-line
educated by the TMR Processor.
FEATURES
 60 Dual (1oo2D) input channels
per module
 Comprehensive diagnostics
and self-test
 Line monitoring on a per
channel basis
 2500V dc Opto-Isolation
 On-board 1ms resolution
Sequence of Events reporting
 Hot replaceable
 Module fault and status
indicators
 IEC 61508, SIL 3 safety
applications
T8402 Trusted Dual 24
Vdc Digital Input