The **IDEC MicroSmart FC4A-R161** is a Programmable Logic Controller (PLC) CPU module designed for industrial automation. It belongs to the MicroSmart series, known for its compact size and modularity. --- ### ## 1. Technical Specifications The FC4A-R161 is an All-in-One type CPU module. Below is a breakdown of its primary electronic characteristics: | Feature | Specification | | :--- | :--- | | **Input Type** | 24V DC (Sink/Source) | | **Number of Inputs** | 9 Inputs | | **Output Type** | Relay Output | | **Number of Outputs** | 7 Outputs | | **Power Supply** | 100 - 240V AC | | **Mounting** | 35mm DIN Rail or Panel Mount | | **Programming Port** | RS232C (Mini-DIN 8-pin) | --- ### ## 2. Core Electronic Components #### ### A. Input Circuitry The module features **9 Digital Inputs**. These are internally isolated to protect the CPU logic from external surges. * **Voltage:** 24V DC. * **Logic:** Can be wired as either "Sink" (connecting to 0V) or "Source" (connecting to +24V). * **Filtering:** Includes electronic noise filters to prevent "chattering" from mechanical switches. #### ### B. Output Circuitry (Relay) The **7 Relay Outputs** act as dry contacts (mechanical switches) controlled by the PLC. * **Voltage Range:** Can handle both AC (up to 240V) and DC (up to 30V). * **Current Rating:** Typically rated for 2A per point. * **Benefit:** Since they are relays, they provide physical galvanic isolation between the PLC electronics and the load (motors, solenoids, or lights). #### ### C. Power Supply Section This specific model features a built-in AC-to-DC converter. * It accepts a wide range of AC input (100V to 240V). * It provides an internal **24V DC auxiliary power supply** (limited current) which can be used to power the input sensors, reducing the need for an external power brick. --- ### ## 3. Communication and Expansion * **Serial Port:** Features an RS232C port for uploading/downloading ladder logic or connecting to an HMI (Human Machine Interface). * **Memory:** Utilizes EEPROM for program storage, meaning no battery is strictly required for program backup (though a battery can be used for data registers). * **Expansion:** The electronic bus on the right side of the unit allows for adding additional I/O modules if the initial 16 points are insufficient.