Technical Specifications of T8442

Manufacturer: ICS Triplex (Rockwell Automation)

Model: T8442

Catalog: Trusted TMR System

Description: 40 Channel 24 Vdc Digital Input FTA

Origin: United States (US)

Supply Ratings: 20 – 32 Vdc, 22 W maximum power.

Input Channels: 40 channels per FTA for digital field devices.

Field Device Connections: Industry standard 2-wire termination.

Mounting Type: Standard DIN rail compatibility.

Operating Voltage: 24 Vdc nominal operation.

Power Supply and Channel Protection

The T8442 derives field power from dual 24 Vdc feeds. Diodes common these feeds on the FTA for redundancy. A green LED indicates the presence of field power. Each channel includes a 50 mA fuse for current limiting. This fuse protects the field loop from overcurrent conditions. The incoming digital signal passes directly to the input module. Line monitoring components detect open circuits or short circuits. The input module uses these thresholds for alarm detection.

Connectors and SmartSlot Features

A 96-way socket (SK1) terminates the cable between the input module and FTA. SmartSlot Version 1 signals connect through SK1. A second 96-way socket (SK2) supports SmartSlot connections. Note that SmartSlot Version 2 does not use the SK2 connector. Dual DC field power supplies connect via a 5-way terminal block (PWR TB). The 40 input signals use 2-wire arrangements. These terminate on twelve 3-way terminal blocks and two 2-way terminal blocks.

Installation Guide

Mount the T8442 on a standard DIN rail in a control cabinet.

Connect dual 24 Vdc field power supplies to the PWR TB terminal block.

Verify the green LED illuminates to confirm power integrity.

Wire field devices to the appropriate input channels using 2-wire connections.

Connect the T8403 input module to SK1 using a 96-way cable.

For SmartSlot Version 1, also connect SK2 as required.

Test each channel for proper signal detection and fuse protection.

Package Contents

One ICS Triplex T8442 Field Termination Assembly.

Pre-installed terminal blocks (12 x 3-way, 2 x 2-way).

One 5-way power terminal block (PWR TB).

Frequently Asked Questions (FAQ)

Q: Which input module works with the T8442 FTA?
A: The T8442 is designed specifically for the Trusted T8403 24 Vdc Digital Input Module. They must be used together.

Q: What is the purpose of the per-channel fuse?
A: Each channel has a 50 mA fuse that limits current in the field loop. This protects both the field device and the input module.

Q: Can I hot-swap the input module with this FTA?
A: Yes, the SmartSlot feature supports ‘one to many’ hot replacement of input modules. This allows module changes without powering down.

Q: What does the green LED indicate?
A: The green LED shows that field power is present and within specification. No LED means a power supply issue.

Q: Does the T8442 work with SmartSlot Version 2?
A: Yes, but Version 2 does not use the SK2 connector. Only the SK1 connection is required for Version 2 systems.