Description

ICS Triplex T8403C Trusted TMR 24 VDC Digital Input Module

Configured for 24 VDC digital signal acquisition in the Trusted TMR I/O architecture, the ICS Triplex T8403C (T8403C Input Module) provides 40 discrete input channels with configurable thresholds and 50 V reinforced field isolation.

Hardware Specifications

Parameter	Specification
Model	T8403C
Brand	ICS Triplex
Product Type	Trusted TMR 24 VDC Digital Input Module
Origin	USA
Weight	1.15 kg
Dimensions	3 x 30.3 x 26.4 cm estimated shipping size
Operating Temp	Not specified in supplied data
Power Consumption	Maximum power dissipation: 29 W
Number of Inputs	40
Input Type	Digital Input
Nominal Field Voltage	24 VDC
Field Commo	50 V reinforced
Impedance	5 kOhm
Measurement Range	-6 to +36 VDC
Input Thresholds	Configurable
Maximum Withstanding Voltage	+/-50 VDC
Safety Accuracy	0.5 VDC
Field Connection	3-wire field device connection
Field Power	Fused field power supply per channel
Mounting	DIN rail compatible
Redundancy Architecture	Triple Modular Redundancy (TMR)
Inter-Module Bus	IMB
Status Indicators	3 Healthy, 1 Active, 1 Standby, 1 Educated

TMR Safety Architecture and Digital Input Processing

The T8403C uses a Triple Modular Redundancy (TMR) architecture for digital input acquisition. Each module contains three module slices that process the input data independently.

The Field Processing Unit (FPU) receives data from the three slices and performs a 2oo3 vote on each input data bit. Therefore, the voting process determines the reported input state from redundant processing paths.

The module interfaces with the Trusted Inter-Module Bus (IMB), which distributes module power and communication with the Trusted TMR Processor. In addition, the field interface provides direct connections for the external digital input circuits.

The supplied data specifies 50 V reinforced field isolation. Furthermore, each channel incorporates a fused field power supply, while the field interface supports 3-wire device connections.

The front panel provides six status LEDs. Three Healthy indicators correspond to the individual module slices, while Active, Standby, and Educated indicators are controlled by the FPU.

Frequently Asked Questions (FAQ)

Q: How many digital inputs does the ICS Triplex T8403C provide?
A: The T8403C provides 40 digital input channels per VFTA.

Q: How does the T8403C process redundant input data?
A: Three module slices process the input data, and the FPU performs a 2oo3 vote on each data bit.

Q: What input voltage range does the T8403C specify?
A: The supplied specification lists a measurement range of -6 to +36 VDC, with configurable input thresholds and +/-50 VDC maximum withstanding voltage.

Field Installation Guidelines

• Install the T8403C according to the applicable Trusted system hardware installation requirements.
• Verify the field wiring before energizing the module. Confirm correct polarity and terminal allocation for each digital input.
• Use the specified 3-wire field connection arrangement where applicable.
• Keep field signal wiring separated from high-voltage power and high-current switching conductors to reduce electrical interference.
• Connect cable shields according to the plant grounding and control-system wiring standard. Avoid creating unintended ground loops.
• Verify the field supply voltage remains within the specified input measurement range before connecting external devices.
• Check each channel fuse and field power circuit before commissioning.
• Confirm the three Healthy indicators and the Active, Standby, and Educated status indicators after installation.
• Do not apply voltages beyond the stated +/-50 VDC maximum withstanding specification.
• Confirm correct IMB seating and module engagement before system startup.

Specifications

• Brand: ICS Triplex

Advantages

• High reliability in industrial environments
• Supports continuous operation
• Compatible with major PLC/DCS systems