In real industrial control systems, machines interact continuously with sensors, switches, motors, valves, and other field devices. If signal conversion between field devices and controller logic is unstable, systems can display incorrect readings, delayed responses, or unsafe output behavior. This risk increases in fast production lines and safety-monitored environments. PLC I/O modules solve this by acting as the electrical interface between field signals and PLC processing logic.
| Image | Part Number / Manufacturer | Description / Specs | MOQ | Datasheet | RFQ | |
|---|---|---|---|---|---|---|
| 73G-OV10 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG OUTPUT MODULE | 1 | ||||
| 73G-IV10B Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG INPUT MODULE | 1 | ||||
| 73G-II420 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG INPUT MODULE | 1 | ||||
| IDC5Q Manufacturer: Sensata-Crydom Category: I O Relay Modules | DC INPUT MODULE 12-60V | 1 | ||||
| 73G-ITCK Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG INPUT MODULE | 1 | ||||
| 73G-OV5 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG OUTPUT MODULE | 1 | ||||
| 5535868 Manufacturer: Phoenix Contact Category: I O Relay Modules | OUTPUT MODULE | 1 | ||||
| 73G-OI420 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG OUTPUT MODULE | 1 | ||||
| 73G-IV5 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG INPUT MODULE | 1 | ||||
| 73G-ITCJ Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG INPUT MODULE | 1 | ||||
| 73G-OI020 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG OUTPUT MODULE | 1 | ||||
| 73G-IV10 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG INPUT MODULE | 1 | ||||
| 73G-IVAC120 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG INPUT MODULE | 1 | ||||
| SLO48CRA4 Manufacturer: Weidmüller Category: I O Relay Modules | DC OUTPUT MODULE 4A | 1 | ||||
| SLI120CR Manufacturer: Weidmüller Category: I O Relay Modules | AC INPUT MODULE 120V | 1 | ||||
| 73G-II5000 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG INPUT MODULE | 1 | ||||
| G3R-ODX02SN DC5-24 Manufacturer: Omron Automation and Safety Category: I O Relay Modules | DC OUTPUT MODULE 2A | 1 | ||||
| G3R-OD201SN DC5-24 Manufacturer: Omron Automation and Safety Category: I O Relay Modules | DC OUTPUT MODULE 1.5A | 1 | ||||
| 73G-ITR100 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG INPUT MODULE | 1 | ||||
| 73L-OI420 Manufacturer: Grayhill Inc. Category: I O Relay Modules | ANALOG OUTPUT MODULE | 1 |
PLC I/O modules are typically selected during early automation system wiring and control design because field wiring layout, control logic mapping, and signal conditioning depend on module specifications. When a PLC I/O module reaches end-of-life, replacement can be difficult if signal conditioning behavior, isolation rating, or channel mapping changes.
This is common in industrial systems that remain operational for more than ten years. Maintenance teams often require the same I/O module models to avoid rewiring or control program modification. Even small signal timing or electrical tolerance differences can affect process stability.
Delays in sourcing compatible PLC I/O modules can lead to production downtime and increased maintenance cost.
Maketronics assists global engineering and procurement teams with reliable sourcing of both active and obsolete PLC I/O Modules.
A PLC I/O module connects field devices to a PLC by converting sensor signals into readable data and controller commands into actuator control signals.
Digital modules handle on/off signals, while analog modules process variable signals such as temperature, pressure, or flow levels.
Isolation protects the controller from electrical noise, voltage spikes, and ground loop issues, ensuring reliable system operation.
Signal compatibility, isolation rating, channel mapping, and communication compatibility must be verified to maintain system stability.