Y301-220/222 Technical Manual

Y301-220	Y301-222

• Specification

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Contents

1. Overview
2. Default Settings
3. Modbus Register Map
4. Command Examples
5. Parameter Configuration
6. Automation Rules
7. Troubleshooting

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1. Overview

This manual describes the Modbus RTU communication commands for the Y301-220 and Y301-222 I/O modules.

Model	DI	DO	AI	Description
Y301-220	2	2	0	Dual input + dual relay
Y301-222	2	2	2	Dual input + dual relay + dual analog input

Frame format: [slave address][function code][data][CRC low][CRC high]

The examples below use slave address 0x01. Replace it with the actual device address in your application.

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2. Default Settings

Parameter	Default
Slave address	1
Baud rate	9600 bps
Data bits	8
Parity	None
Stop bits	1

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3. Modbus Register Map

3.1 Digital Input (DI) - Function Code 0x02

Channel	Address	Supported Models
DI1	0x0000	Y301-220, Y301-222
DI2	0x0001	Y301-220, Y301-222

Return value: 0 = inactive, 1 = active.

3.2 Digital Output (DO) - Function Code 0x01/0x05

Channel	Address	Supported Models
DO1	0x0000	Y301-220, Y301-222
DO2	0x0001	Y301-220, Y301-222

Write value: 0x0000 = open, 0xFF00 = closed.

3.3 Analog Input (AI) - Function Code 0x04 (Y301-222 only)

Channel	Address	Description
AI1 voltage	0x0000	Voltage value in mV
AI1 current	0x0001	Current value in uA
AI2 voltage	0x0002	Voltage value in mV
AI2 current	0x0003	Current value in uA

Each AI channel can be wired for either voltage or current. The other reading is invalid.

3.4 Configuration Registers - Function Code 0x03/0x06

Address	Parameter	Range	Default
0x003E	Slave address	1-255	1
0x0057	Baud rate	600-230400	9600
0x0059	Data bits	8 or 9	8
0x005A	Stop bits	1 or 2	1
0x005B	Parity	0=None, 1=Odd, 2=Even	0

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4. Command Examples

4.1 Read Digital Inputs

Read DI1:

Request:  01 02 00 00 00 01 B9 CA
Response: 01 02 01 [status] [CRC]

Read DI2:

Request: 01 02 00 01 00 01 E8 0A

4.2 Read Digital Output Status

Read DO1:

Request:  01 01 00 00 00 01 FD CA
Response: 01 01 01 [status] [CRC]

Read DO2:

Request: 01 01 00 01 00 01 AC 0A

4.3 Control Digital Outputs

Operation	Command
Open DO1	01 05 00 00 00 00 CD CA
Close DO1	01 05 00 00 FF 00 8C 3A
Open DO2	01 05 00 01 00 00 9C 0A
Close DO2	01 05 00 01 FF 00 DD FA

4.4 Read Analog Inputs (Y301-222 only)

Read AI1 voltage:

Request:  01 04 00 00 00 01 31 CA
Response: 01 04 02 [high byte] [low byte] [CRC]

Read AI1 current:

Request: 01 04 00 01 00 01 60 0A

Read AI2 voltage:

Request: 01 04 00 02 00 01 90 0A

Read AI2 current:

Request: 01 04 00 03 00 01 C1 CA

4.5 Quick Reference Table

Operation	Request (Hex)
Read DI1	01 02 00 00 00 01 B9 CA
Read DI2	01 02 00 01 00 01 E8 0A
Read DO1	01 01 00 00 00 01 FD CA
Read DO2	01 01 00 01 00 01 AC 0A
Open DO1	01 05 00 00 00 00 CD CA
Close DO1	01 05 00 00 FF 00 8C 3A
Open DO2	01 05 00 01 00 00 9C 0A
Close DO2	01 05 00 01 FF 00 DD FA
Read AI1 voltage	01 04 00 00 00 01 31 CA
Read AI1 current	01 04 00 01 00 01 60 0A
Read AI2 voltage	01 04 00 02 00 01 90 0A
Read AI2 current	01 04 00 03 00 01 C1 CA

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5. Parameter Configuration

5.1 Change the Slave Address

Set the slave address to 5:

Request:  01 06 00 3E 00 05 E8 00
Response: 01 06 00 3E 00 05 E8 00

After the change, subsequent commands must use the new address.

5.2 Change the Baud Rate

Common baud-rate values:

Baud Rate	Value
9600	0x00002580
19200	0x00004B00
38400	0x00009600
115200	0x0001C200

Power-cycle the device after changing the baud rate.

5.3 Restore Factory Defaults

Hold the Reload button for 3-15 seconds to restore:

• Slave address -> 1
• Baud rate -> 9600
• All parameters -> factory defaults

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6. Automation Rules

The Y301-220/222 support DI -> DO automation, and the Y301-222 also supports AI threshold triggering.

6.1 Automation Register Map

Rules start at address 0x0080. Each rule uses 8 registers (16 bytes). Up to 4 rules are supported, with 2 rules per DO.

Offset	Field	Description
+0	Mode	Rule type (see table below)
+1	Action	0=open, 1=close, 2=toggle
+2	DO index	Target relay, starting from 1
+3	Trigger index	Source DI or AI, starting from 1
+4-5	Parameter 1	Mode-dependent, 32-bit
+6-7	Parameter 2	Mode-dependent, 32-bit

6.2 Rule Modes

Mode	Name	Description
0	DI follow	DO follows the DI state
1	DI inverse	DO is the inverse of the DI state
2	Pulse	DO outputs a pulse for parameter1 ms when DI triggers
3	Delayed ON	DO closes parameter1 ms after DI closes
4	Delayed OFF	DO opens parameter1 ms after DI opens
5	Cycle	DO toggles periodically, parameter1=ON time, parameter2=OFF time
10	AI threshold	Trigger when AI exceeds parameter1 (Y301-222 only)

6.3 Example: DO1 Follows DI1

Configuration:

Field	Value
Mode	0x0000 (DI follow)
Action	0x0001 (close when DI=1)
DO index	0x0001
Trigger index	0x0001
Parameter 1	0x00000000
Parameter 2	0x00000000

Modbus command:

01 10 00 80 00 08 10 00 00 00 01 00 01 00 01 00 00 00 00 00 00 00 00 0D FE

6.4 Example: Close DO1 When AI1 Exceeds 5 V (Y301-222 only)

Configuration:

Field	Value
Mode	0x000A (AI threshold)
Action	0x0001 (close)
DO index	0x0001
Trigger index	0x0001 (AI1)
Parameter 1	0x00001388 (5000 mV)
Parameter 2	0x000003E8 (minimum trigger interval 1000 ms)

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7. Troubleshooting

Symptom	Cause	Solution
No response	Wrong address or baud rate	Check settings and try broadcast address 0
CRC error	Wiring issue or interference	Check RS485 polarity and add termination resistors
DO does not switch	Load exceeds rating	Reduce the load and verify contact ratings
DI always reads 0	Wiring error	Check COM/DI wiring and input voltage
AI reading is abnormal	Wrong wiring mode	Verify voltage/current wiring; each channel supports only one mode at a time

LED Indicators

LED	Status	Meaning
POWER	Solid on	Power is normal
TX	Flashing	Data is being transmitted
RX	Flashing	Data is being received
DI1/DI2	On	Input is active
DO1/DO2	On	Relay is closed

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• Manufacturer: Hunan YenGear Tech Co., Ltd.
• Email: hi@yengear.com
• Website: www.yengear.com