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Y305 PLC I/O Modules Specification: Y305-4400/4421/8800/8821
Y305 PLC I/O modules run local control programs and provide either 4 digital inputs and 4 digital outputs or 8 of each. Y305-4421 and Y305-8821 add two 0–10 V inputs and one 0–10 V output.
User Manual · Technical Manual · Documentation Index
Contents
1. Model selection
| Model | Digital inputs (DI) | Digital outputs (DO) | Analog inputs (AI) | Analog outputs (AO) |
|---|---|---|---|---|
| Y305-4400 | 4 | 4 | 0 | 0 |
| Y305-4421 | 4 | 4 | 2 | 1 |
| Y305-8800 | 8 | 8 | 0 | 0 |
| Y305-8821 | 8 | 8 | 2 | 1 |
The four positions after Y305 represent DI / DO / AI / AO. A zero means no channels of that type; the AO position remains present when it is zero.
| Selection | Ordering information |
|---|---|
| Output hardware | Relay by default; DC NPN transistor optional. Specify this separately from the four-digit model. |
| RS485 | Specify whether RS485 is required and whether one or two ports are needed. The model code does not specify port count. |
| RTC | Specify whether clock functions are required; availability depends on the selected hardware combination. |
| High-speed counting or pulse output | Specify the signals, channels, and rates required. Use only hardware rated for those functions; relay outputs cannot generate high-speed pulses. |
Match the order record to the delivered options. Relay and NPN outputs are different hardware, not a software setting. Analog channels on 4421/8821 are voltage channels; they do not provide direct current-loop, thermocouple, or RTD inputs.
2. Electrical specifications
2.1 Supply and digital inputs
| Parameter | Value |
|---|---|
| Nominal module supply | 24 VDC |
| DI count | 4 on 4400/4421; 8 on 8800/8821 |
| Input arrangement | S/S to +24 V; a dry contact or compatible sinking signal connects Xn to 0 V |
| Channel labels | X0–X3 or X0–X7 |
24 VDC is the nominal supply, not a permitted voltage range. Obtain the unit's supply tolerance, current consumption, and inrush before sizing the supply. Match powered sensors to the DI thresholds, input current, filter time, and leakage limits. Do not apply AC to supply or DI terminals.
2.2 Digital outputs
| Parameter | Relay hardware | NPN transistor hardware |
|---|---|---|
| Output action | Switches a contact circuit | Sinks DC load current |
| Stated load voltage | AC 220 V or DC 30 V | Use the output-voltage rating for the ordered hardware |
| Stated current ceiling | 5 A, subject to the load conditions below | 3 A, subject to the load conditions below |
| AC loads | Subject to the applicable contact/load rating | Prohibited |
| High-speed pulse output | Not supported through relay contacts | Requires channel-specific hardware ratings |
| Channel labels | Y0–Y3 or Y0–Y7 | Y0–Y3 or Y0–Y7 |
These figures alone do not establish a per-channel continuous-load rating or a common-terminal rating. They do not define motor or inductive-load capability, inrush, or simultaneous channel loading. Obtain the applicable load-category, common-terminal, and derating ratings before connecting a load. Use a rated interposing device where direct switching is unsuitable; its input or coil must also meet the PLC output rating.
2.3 Analog I/O: Y305-4421 and Y305-8821
| Parameter | Value |
|---|---|
| Channels | 2 AI + 1 AO |
| Signal range | 0–10 V |
| Raw range / resolution | 0–4095 / 12 bits |
| Input terminals | AD0, AD1 |
| Output terminal | DA0 |
| Signal reference | GND, wired to the unit's reference arrangement |
Nominal voltage = raw value × 10 / 4095. Resolution is not an accuracy specification. Match sensors and receivers to the unit's accuracy, update time, AI impedance, AO load capability, and reference/isolation limits. Do not apply an external voltage to DA0 or connect 4–20 mA directly to these channels.
For measurement registers and scaling, see the Analog and PID Guide.
3. Programming and interfaces
| Item | Description |
|---|---|
| Local control | User PLC program |
| Engineering software | GX Works2 programming with an FX3U-style device/instruction model; use the setup specified for the hardware and firmware |
| RS485 option | Up to two fitted ports; Modbus RTU master/slave or non-protocol RS communication |
| Network integration | An external gateway can connect an RS485 bus to a network; select it for the required protocol and application |
RS and ADPRW cannot operate simultaneously. Protocol settings and register access are in the Technical Manual; connection and transaction workflows are in the Modbus Integration Guide.
4. Dimensions
| Digital size | Models | Enclosure, mm | Relay PCB outline, mm |
|---|---|---|---|
| 4 DI + 4 DO | Y305-4400 / Y305-4421 | 96 × 99 × 41 | 92.50 × 87.00 |
| 8 DI + 8 DO | Y305-8800 / Y305-8821 | 125 × 99 × 41 | 122.80 × 87.80 |
Enclosure dimensions are width × height × depth. PCB outlines are the two edge lengths in the relay drawings; their order does not indicate enclosure orientation. Use the drawing for the delivered hardware to locate mounting holes, terminals, and required clearances; do not use PCB dimensions as enclosure dimensions or as a drilling template.
5. Installation limits
Select the enclosure and installation site using the unit's environmental, protection, isolation, and EMC limits. Product certification requirements must match the intended installation.
Do not use Y305 as a safety PLC or as the sole protective control. Provide independent safety functions where required. Test startup, STOP, power loss, and communication recovery with production loads isolated; do not assume an automatic safe output state. Installation steps are in the User Manual.