Field signals
Digital status, relay control, voltage or current input, and analog output.
RS485 Modbus I/O Modules for Field Data Acquisition and Control
Connect digital and analog field signals to PLCs, SCADA systems, and edge controllers. Choose from compact digital I/O, mixed I/O with relay outputs, and high-density DI, AI, or AO modules.
- DI, relay DO, AI, and AO models
- RS485 Modbus RTU across the Y301 family
- RS232, TTL, and Modbus ASCII on selected models
Host systems
PLCs, SCADA systems, and edge controllers with a compatible serial interface and register map.
Serial communication
RS485 Modbus RTU across the family; additional interfaces and ASCII on selected models.
Installation
DIN-rail modules for control panels. Confirm supply voltage and environmental limits by model.
Connect field I/O to a serial Modbus host
A Y301 module sits between field signals or loads and the PLC, SCADA system, or edge controller that reads and writes its registers.
- 01
Signal sideConnect compatible inputs, relay loads, or analog outputs for the selected model.
- 02
Module roleThe module exposes field states and values to the host; it does not replace the controller.
- 03
Host sideMatch the interface, protocol mode, baud rate, address, and register map.
Start with the I/O task, then compare channel count and electrical limits
MiniLink, ControlLink, and FlexPoint organize the Y301 range by I/O combination and project task.
MiniLink Family
Compact one- or two-channel digital I/O for status monitoring and relay control.
Best fit
- Space-constrained panels
- Simple DI or relay DO tasks
Y301-110 · Y301-200 · Y301-020
View MiniLink Models
ControlLink Family
Combined digital input and relay output, with analog input and local rules on selected models.
Best fit
- Monitoring and relay control in one module
- Mixed digital and analog input requirements
Y301-220 · Y301-222 · Y301-440 · Y301-444 · Y301-880
View ControlLink Models
FlexPoint Family
Dedicated DI, AI, or AO modules for higher channel counts and signal-specific expansion.
Best fit
- Six, eight, or sixteen input channels
- Four, six, or eight analog output channels
Y301-600 · Y301-800 · Y301-G00 · Y301-006 · Y301-008 · Y301-00G · Y301-0004 · Y301-0006 · Y301-0008
View FlexPoint ModelsMatch the module to the signal and load
Use these three wiring patterns to identify the right product family. Final selection still depends on signal range, load, interface, supply, and installation conditions.
Start with MiniLink or FlexPoint DI models
Monitor switches and equipment status
- Signal
- Dry-contact or compatible wet-contact DI
- Device or load
- Switches, buttons, level contacts, and equipment status contacts
- Confirm before selection
- Input voltage, common wiring, isolation, and debounce by model
Compare all 17 Y301 models
Scan the compact model list, then open the detailed comparison for interface and electrical limits before final design or ordering.
3 models
MiniLink
Compact one- or two-channel digital I/O for status monitoring and relay control.
Open detailed comparison
| Model | I/O | Power | Interface / protocol | Signal or load boundary | Best for | Action |
|---|---|---|---|---|---|---|
| Y301-110 | 1 DI + 1 relay DO | 5–36 VDC | RS485; optional RS232 / TTL · Modbus RTU | SPDT relay · 277 VAC 10 A / 28 VDC 10 A | One status input and one relay-control point | |
| Y301-200 | 2 DI | 5–36 VDC | RS485; optional RS232 / TTL · Modbus RTU | Dry / wet contact inputs · opto-isolated | Two-channel status monitoring | |
| Y301-020 | 2 relay DO | 5–36 VDC | RS485; optional RS232 / TTL · Modbus RTU | SPDT relays · 277 VAC 10 A / 28 VDC 10 A | Two relay-control points |
Y301-1105–36 VDC
- Y301-1101 DI + 1 relay DO
Review limits and fit
- Y301-110 · Interface
- RS485; optional RS232 / TTL · Modbus RTU
- Signal / load
- SPDT relay · 277 VAC 10 A / 28 VDC 10 A
- Best for
- One status input and one relay-control point
Y301-2005–36 VDC
- Y301-2002 DI
Review limits and fit
- Y301-200 · Interface
- RS485; optional RS232 / TTL · Modbus RTU
- Signal / load
- Dry / wet contact inputs · opto-isolated
- Best for
- Two-channel status monitoring
Y301-0205–36 VDC
- Y301-0202 relay DO
Review limits and fit
- Y301-020 · Interface
- RS485; optional RS232 / TTL · Modbus RTU
- Signal / load
- SPDT relays · 277 VAC 10 A / 28 VDC 10 A
- Best for
- Two relay-control points
5 models
ControlLink
Combined digital input and relay output, with analog input and local rules on selected models.
Open detailed comparison
| Model | I/O | Power | Interface / protocol | Signal or load boundary | Best for | Action |
|---|---|---|---|---|---|---|
| Y301-220 | 2 DI + 2 relay DO | 5–36 VDC | RS485; optional RS232 / TTL · Modbus RTU | 10 A relays · up to 4 local rules | Compact monitoring and relay control | |
| Y301-222 | 2 DI + 2 relay DO + 2 AI | 5–36 VDC | RS485; optional RS232 / TTL · Modbus RTU | 0–10 V / 4–20 mA AI · 16-bit · up to 4 rules | Mixed digital and sensor monitoring | |
| Y301-440 | 4 DI + 4 relay DO | 5–36 VDC | RS485; optional RS232 / TTL · Modbus RTU | 10 A relays · up to 8 local rules | Four-point monitoring and control | |
| Y301-444 | 4 DI + 4 relay DO + 4 AI | 5–36 VDC | RS485; optional RS232 / TTL · Modbus RTU | 0–10 V / 0–5 V / 4–20 mA AI · up to 8 rules | Mixed four-channel monitoring and control | |
| Y301-880 | 8 DI + 8 relay DO | 5–36 VDC | RS485; optional RS232 / TTL · Modbus RTU | 10 A relays · up to 16 local rules | Higher-density digital monitoring and control |
Y301-220/2225–36 VDC
- Y301-2202 DI + 2 relay DO
- Y301-2222 DI + 2 relay DO + 2 AI
Review limits and fit
- Y301-220 · Interface
- RS485; optional RS232 / TTL · Modbus RTU
- Signal / load
- 10 A relays · up to 4 local rules
- Best for
- Compact monitoring and relay control
- Y301-222 · Interface
- RS485; optional RS232 / TTL · Modbus RTU
- Signal / load
- 0–10 V / 4–20 mA AI · 16-bit · up to 4 rules
- Best for
- Mixed digital and sensor monitoring
Y301-440/4445–36 VDC
- Y301-4404 DI + 4 relay DO
- Y301-4444 DI + 4 relay DO + 4 AI
Review limits and fit
- Y301-440 · Interface
- RS485; optional RS232 / TTL · Modbus RTU
- Signal / load
- 10 A relays · up to 8 local rules
- Best for
- Four-point monitoring and control
- Y301-444 · Interface
- RS485; optional RS232 / TTL · Modbus RTU
- Signal / load
- 0–10 V / 0–5 V / 4–20 mA AI · up to 8 rules
- Best for
- Mixed four-channel monitoring and control
Y301-8805–36 VDC
- Y301-8808 DI + 8 relay DO
Review limits and fit
- Y301-880 · Interface
- RS485; optional RS232 / TTL · Modbus RTU
- Signal / load
- 10 A relays · up to 16 local rules
- Best for
- Higher-density digital monitoring and control
9 models
FlexPoint
Dedicated DI, AI, or AO modules for higher channel counts and signal-specific expansion.
Open detailed comparison
| Model | I/O | Power | Interface / protocol | Signal or load boundary | Best for | Action |
|---|---|---|---|---|---|---|
| Y301-600 | 6 DI | 7–30 VDC | RS485 / RS232 · Modbus RTU / ASCII | Opto-isolated DI · 3.3–24 VDC active input | Six digital status points | |
| Y301-800 | 8 DI | 7–30 VDC | RS485 / RS232 · Modbus RTU / ASCII | Opto-isolated DI · 3.3–24 VDC active input | Eight digital status points | |
| Y301-G00 | 16 DI | 7–30 VDC | RS485 / RS232 · Modbus RTU / ASCII | Opto-isolated DI · 3.3–24 VDC active input | Sixteen digital status points | |
| Y301-006 | 6 AI | 7–30 VDC | RS485 / RS232 · Modbus RTU / ASCII | 0–10 V / 4–20 mA · 12-bit · ±0.5% FS | Six analog measurement points | |
| Y301-008 | 8 AI | 7–30 VDC | RS485 / RS232 · Modbus RTU / ASCII | 0–10 V / 4–20 mA · 12-bit · ±0.5% FS | Eight analog measurement points | |
| Y301-00G | 16 AI | 7–30 VDC | RS485 / RS232 · Modbus RTU / ASCII | 0–10 V / 4–20 mA · 12-bit · ±0.5% FS | Sixteen analog measurement points | |
| Y301-0004 | 4 AO | 12–30 VDC | Isolated RS485; optional RS232 · RTU / ASCII | 0–10 V / 4–20 mA · 14-bit · ±0.1% FS | Four analog setpoint outputs | |
| Y301-0006 | 6 AO | 12–30 VDC | Isolated RS485; optional RS232 · RTU / ASCII | 0–10 V / 4–20 mA · 14-bit · ±0.1% FS | Six analog setpoint outputs | |
| Y301-0008 | 8 AO | 12–30 VDC | Isolated RS485; optional RS232 · RTU / ASCII | 0–10 V / 4–20 mA · 14-bit · ±0.1% FS | Eight analog setpoint outputs |
Y301-600/800/G007–30 VDC
- Y301-6006 DI
- Y301-8008 DI
- Y301-G0016 DI
Review limits and fit
- Y301-600 · Interface
- RS485 / RS232 · Modbus RTU / ASCII
- Signal / load
- Opto-isolated DI · 3.3–24 VDC active input
- Best for
- Six digital status points
- Y301-800 · Interface
- RS485 / RS232 · Modbus RTU / ASCII
- Signal / load
- Opto-isolated DI · 3.3–24 VDC active input
- Best for
- Eight digital status points
- Y301-G00 · Interface
- RS485 / RS232 · Modbus RTU / ASCII
- Signal / load
- Opto-isolated DI · 3.3–24 VDC active input
- Best for
- Sixteen digital status points
Y301-006/008/00G7–30 VDC
- Y301-0066 AI
- Y301-0088 AI
- Y301-00G16 AI
Review limits and fit
- Y301-006 · Interface
- RS485 / RS232 · Modbus RTU / ASCII
- Signal / load
- 0–10 V / 4–20 mA · 12-bit · ±0.5% FS
- Best for
- Six analog measurement points
- Y301-008 · Interface
- RS485 / RS232 · Modbus RTU / ASCII
- Signal / load
- 0–10 V / 4–20 mA · 12-bit · ±0.5% FS
- Best for
- Eight analog measurement points
- Y301-00G · Interface
- RS485 / RS232 · Modbus RTU / ASCII
- Signal / load
- 0–10 V / 4–20 mA · 12-bit · ±0.5% FS
- Best for
- Sixteen analog measurement points
Y301-0004/0006/000812–30 VDC
- Y301-00044 AO
- Y301-00066 AO
- Y301-00088 AO
Review limits and fit
- Y301-0004 · Interface
- Isolated RS485; optional RS232 · RTU / ASCII
- Signal / load
- 0–10 V / 4–20 mA · 14-bit · ±0.1% FS
- Best for
- Four analog setpoint outputs
- Y301-0006 · Interface
- Isolated RS485; optional RS232 · RTU / ASCII
- Signal / load
- 0–10 V / 4–20 mA · 14-bit · ±0.1% FS
- Best for
- Six analog setpoint outputs
- Y301-0008 · Interface
- Isolated RS485; optional RS232 · RTU / ASCII
- Signal / load
- 0–10 V / 4–20 mA · 14-bit · ±0.1% FS
- Best for
- Eight analog setpoint outputs
Need help choosing? Get a model recommendation.
Confirm more than the channel count
The correct model depends on the signal, electrical load, host connection, power, environment, and local-control requirement.
- 01
Signal direction and type
Identify each DI, relay DO, AI, or AO point and whether the signal is digital, voltage, or current.
- 02
Channel count
Count the required points and allow only the project margin you can justify.
- 03
Range or load
Confirm analog range or relay operating voltage, steady current, inrush current, and load type.
- 04
Host interface and protocol
Confirm RS485, RS232, or TTL availability and the required Modbus mode for the selected model.
- 05
Power and environment
Check supply voltage, temperature, humidity, enclosure, wiring, and installation clearance.
- 06
Local rules and accessories
Confirm whether local rules, retention, converters, termination, protection, or external contactors are required.
FAQ
Questions that change model selection. Check the product family, signal type, communication option, load, and required documents before final selection.
Which Y301 series should I start with?
Start with MiniLink for compact one- or two-channel digital I/O, ControlLink for combined digital input and relay output with analog input on selected models, and FlexPoint for dedicated higher-channel-count DI, AI, or AO expansion. Then compare channel count and model-specific electrical limits.
How do I choose between DI, DO, AI, and AO models?
Use DI for discrete status signals, relay DO for on/off load control, AI for supported voltage or current measurements, and AO for supported voltage or current setpoints. Confirm signal range, common wiring, isolation, accuracy, and load requirements in the selected model specification.
Which serial interfaces and Modbus modes are available?
RS485 Modbus RTU is available across the documented Y301 family. RS232, TTL, and Modbus ASCII are available only on selected models. Match the host interface, protocol mode, baud rate, address, and register map to the selected model.
Can relay outputs switch pumps, motors, or other inductive loads directly?
Do not select a relay from steady current alone. Check operating voltage, inrush current, switching frequency, and load type. Y301-110 and Y301-020 relay contacts are rated 277 VAC 10 A or 28 VDC 10 A under the designated specification, but the application may still require protection or an external contactor.
What information is needed for a model recommendation?
Share the I/O type and channel count, signal range or load, host interface and protocol, supply voltage, installation environment, and any local rule requirement. Submit the conditions you know; missing details can be confirmed later.
Where can I find wiring diagrams, register maps, and manuals?
Open the detailed comparison above and follow the selected model specification for electrical and mechanical limits. Use the linked technical reference for wiring, configuration, communication settings, and register information.
Find the right Y301 model
Share the I/O and project conditions you know. We will use them to narrow the product family and model.
- I/O type and channel count
- Signal range or controlled load
- Host interface and protocol
- Supply voltage and installation environment