Honeywell FC-TDIO51 Digital Input/Output Module

Signal Acquisition
The module connects to external switch signals (such as buttons, sensor contacts, relay status) via terminal blocks, supporting dry contact (non-voltage) or wet contact (DC 5-30V) inputs.

Level Conversion

Optical Isolation
Input signals are isolated by optocouplers to prevent external electrical interference (such as surges, ground loops) from affecting internal circuits.

Status Buffering
Converted digital signals are stored in internal registers for CPU reading and processing

Instruction Reception
The CPU receives output control instructions (such as set, reset, pulse output) from the host computer (e.g., PLC, DCS) via communication interfaces.

Drive Control

Protection Mechanisms
Output channels integrate overcurrent protection (e.g., automatic cut-off during short circuits) and freewheeling diodes for inductive loads (suppressing back EMF)

Input Interface
Includes multiple independent channels, each integrated with filter circuits (eliminating signal jitter), optocouplers (isolation voltage ≥500V AC), and signal conditioning circuits.

Output Interface
Configures different drive circuits based on output types (relay/transistor), supports sink/source current modes, with single-channel maximum load capacity up to 2A/30V DC.

Supports Modbus RTU protocol (via RS485 interface) for data exchange with host computers.

Optional Ethernet interface (e.g., TCP/IP protocol) for remote configuration and monitoring.

Built-in communication buffer ensures data transmission reliability.

Supports wide voltage input (DC 24V±10% or AC 100-240V), with internal EMI filtering and surge protection circuits.

Isolated power design ensures independent power supply for functional units, enhancing anti-interference capability.

Polling Mode
The host computer periodically sends query instructions, and the module responds by uploading input statuses (e.g., on/off values of DI channels).

Event Triggering
When input status changes (e.g., switch closure) or output execution completes, the module proactively sends event reports to the host computer.

Remote Configuration
The host computer can modify module parameters (e.g., output mode, communication baud rate) via communication protocols.

Built-in Logic
Supports simple logical operations (e.g., AND, OR, NOT) and timing functions (e.g., pulse width modulation), enabling local implementation of basic control logic to reduce host computer load.

Interlocking Control
Configures interlocking relationships between inputs and outputs (e.g., "DO3 outputs high level when DI1 is closed") to achieve local automation independent of the host computer.