M74RSmart I/O module
Flexible I/O expansion for your control system.
CT 4 · DI 4 · DO 8
Versatile I/O for monitoring and control
Expand with up to 3 units
Per M74 or M74P controller
Automatic detection and mapping
Communication setting copying and I/O mapping

Features
M74R FeaturesM74R is a universal smart I/O module that expands the M74 series and can also connect directly to a PLC, PC or touch panel. It provides 4 CT inputs, 4 DI inputs and 8 relay contact outputs. Connect up to 3 M74R units per M74 or M74P controller, or up to 189 units through external communication in a standalone configuration.
Compact construction
At approximately 70% of the volume of competing products, M74R helps make efficient use of control-panel space.
Versatile inputs and outputs
Provides 4 CT inputs, 4 DI inputs and 8 relay contact outputs.
Automatic detection and mapping
Automatically maps I/O through internal communication when connected to M74 series modules.
Universal I/O module
Can interface directly with a PC, PLC or touch panel as a standalone module.
High-speed host communication
Supports Modbus ASCII/RTU and PC-Link at communication speeds up to 115,200 bps.
Automatic copying and setup of communication parameters
Configure one module to automatically assign station numbers 1~63 and copy its settings.
Fully isolated design
A fully isolated design separates the inputs and outputs. The specified terminal pairs are rated for a dielectric strength test of 1,000 V AC for 1 minute.
Module expansion configurations
Connect up to 3 M74R units per M74 or M74P controller, up to 189 units in a standalone external communication configuration, or manage up to 93 M74R units through M74C.
Specifications
View Catalog PDF| General | |
|---|---|
| Model | M74R smart I/O expansion module |
| Supply voltage | 24 V DC |
| Allowable voltage range | 90–110% of rated supply voltage |
| Power consumption | 5 W max. (at maximum load) |
| Display & operation | No display / M74 series expansion module or standalone I/O device connected to a PLC, PC or touch panel |
| Dimensions | 29(W) × 90(H) × 70(D) mm |
| Inputs and outputs | |
| CT inputs | 4 inputs / CT ratio: 1/800 / current range: 0.0~38.0 A / ±3% of FS + 1 digit |
| DI inputs | 4 inputs / contact or non-contact inputs / ON: 1 kΩ max., OFF: 100 kΩ min. |
| Individual contact outputs | 3 outputs / 1a contacts / 250 V AC, 3 A (resistive load) / mechanical life: 10 million operations min. |
| Common contact outputs | 5 outputs / 1a contacts / 250 V AC, 3 A (resistive load) / mechanical life: 10 million operations min. |
| Measurement accuracy · CT | Current range: 0.0~38.0 A / ±3% of FS + 1 digit |
| Control methods | Controlled through M74 or a host PLC, PC or touch panel |
| Communication and expansion | |
| Host communication · RS-485 | Modbus ASCII/RTU, PC-Link or TL-Link / 9,600~115,200 bps (when connected to a host device) |
| Automatic station numbering | Station numbers 1~63 / automatic copying of communication settings |
| Controller expansion | Up to 3 units per M74 or M74P |
| Standalone external communication configuration | Up to 189 units |
| Integrated management through M74C | Up to 93 units / 31 M74 or M74P controllers × 3 M74R units |
| Insulation, Reliability & Environment | |
| EEPROM endurance & retention | At least 4 million write cycles / At least 200 years of data retention |
| Insulation resistance | 100 MΩ min. (500 V DC insulation tester) |
| Insulation construction | Double or reinforced insulation / Dielectric strength of at least 1 kV between measurement input and power supply |
| Dielectric strength | 1,000 V AC, 50/60 Hz, for 1 minute — between input terminals, input and output terminals, and input and power terminals |
| Vibration resistance | 5–55 Hz (1-minute cycle), 0.75 mm double amplitude / 2 hours each in X, Y and Z directions |
| Noise immunity | Noise simulator square wave, 1 μs pulse width / ±1 kV |
| Ambient temperature | Operating: −10 to 50 °C / Storage: −20 to 60 °C |
| Ambient humidity | Operating: 35–85% RH / Storage: 35–85% RH |
| Weight | Approx. 230 g with packaging / Approx. 120 g net |
Dimensions & Wiring
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