GSA-M Series Single Turn Modbus Absolute Encoder
1. Basic Product Parameters
| Parameter | Details/Options |
|---|---|
| Model | GSA-M Series Single Turn Modbus Absolute Encoder |
| Housing Diameter | 38 mm, 50 mm, 58 mm |
| Shaft Diameter | 6 mm, 8 mm, 10 mm (Solid/Hollow) |
| Resolution | Single turn, up to 16-bit |
| Output Code | Binary, Gray, Excess Gray, BCD |
| Interface | Modbus (RS-485) |
| Supply Voltage | 5V; 8–29V |
| Maximum Frequency | 300 kHz |
2. Electrical Data
| Output Format | Consumption Current | Load Current | VOH | VOL |
|---|---|---|---|---|
| Open Collector | ≤80 mA | 40 mA | ≥ Vcc × 70% | ≤ 0.4 V |
| Voltage Output | ≤80 mA | 40 mA | ≥ Vcc – 2.5 V | ≤ 0.4 V |
| Line Driver | ≤150 mA | 60 mA | ≥ 3.4 V | ≤ 0.4 V |
| Push Pull | ≤80 mA | 40 mA | ≥ Vcc – 1.5 V | ≤ 0.8 V |
3. Mechanical Data
| Parameter | Value |
|---|---|
| Start Torque | 4 × 10⁻³ N·m |
| Maximum Axial Load | 29.4 N |
| Maximum Radial Load | 19.6 N |
| Maximum Speed | 3000 rpm |
| Weight | 160 – 200 g |
4. Environmental Data
| Parameter | Range |
|---|---|
| Operating Temp. | -30°C ~ 80°C |
| Storage Temp. | -40°C ~ 80°C |
| Protection Grade | IP54 |
5. Modbus Communication Parameters
| Parameter | Details |
|---|---|
| Transmission | RS-485 |
| Address Range | 1–254 (Default address: 01H) |
| Baud Rate | 4800, 9600 (default), 19200, 38400 |
| Transmission Media | STP |
| Data Frame Format | 1 start bit, 8 data bits, 1 even parity bit, 1 stop bit; no flow control |
| Protocol | Modbus (Request/Response mode) |
6. Modbus Message Format
| Function Code | Function Description | Master Request Format | Slave Response Format | Example |
|---|---|---|---|---|
| 03H | Read Position Value | Address | 03H | Parameter Address | Data Length | Check Code | Address | 03H | Byte Length | Parameter Value | Check Code | Master Example: 01H 03H 00H 00H 00H 02H C4H 0BH Slave Example: 01H 03H 04H 01H F4H 00H 01H 7BH FDH |
| 10H | Preset Current Position | Address | 10H | Parameter Address | Data Length | Byte Length | Parameter Value | Check Code | Address | 10H | Parameter Address | Data Length | Check Code | Master Example: 01H 10H 00H 4AH 00H 02H 04H 00H 00H 00H 00H 77H E0H Slave Example: 01H 10H 00H 4AH 00H 02H 60H 1EH |
| 06H | Write Parameter Value | Address | 06H | Parameter Address | Parameter Value | Check Code | Address | 06H | Parameter Address | Parameter Value | Check Code | Example – Change ID: Master: 01H 06H 00H 44H 00H 02H 48H 1EH Slave: 02H 06H 00H 44H 00H 02H 48H 2DH |
7. Parameter Settings & Register Allocation
| Parameter Name | Register Address | Length | Data Description | Note |
|---|---|---|---|---|
| Change Encoder ID | 0044H | 0001H | High byte fixed at 00H, low byte is the new ID | Takes effect after power cycling |
| Baud Rate Setting | 0045H | 0001H | High byte fixed at 00H, low byte is the baud rate code | Codes: 01: 4800bps; 02: 9600bps; 03: 19200bps; 04: 38400bps |
| Counting Direction | 0046H | 0001H | High byte fixed at 00H, low byte is the counting direction code | 00: Clockwise (increasing); 01: Counterclockwise (decreasing) |
| Preset Current Position | 004AH | 0002H | Four bytes (from high to low) representing the current position value | Preset value must not exceed the physical limit |
8. Parameter Change Examples
| Example | Master Send Message | Slave Response Message | Description |
|---|---|---|---|
| a. Change Encoder ID (01H → 02H) | 01H 06H 00H 44H 00H 02H 48H 1EH | 02H 06H 00H 44H 00H 02H 48H 2DH | Using register 0044H |
| b. Change Baud Rate (to 38400bps, code 04H) | 01H 06H 00H 45H 00H 04H 99H DCH | 01H 06H 00H 45H 00H 04H 99H DCH | Using register 0045H |
| c. Change Counting Direction (to Counterclockwise, code 01H) | 01H 06H 00H 46H 00H 01H A9H DFH | 01H 06H 00H 46H 00H 01H A9H DFH | Using register 0046H |
| d. Preset Current Position (00000000H) | 01H 10H 00H 4AH 00H 02H 04H 00H 00H 00H 00H 77H E0H | 01H 10H 00H 4AH 00H 02H 60H 1EH | Using register 004AH |
9. Selection Process (Five Steps)
| Step | Description |
|---|---|
| 1 | If you already use encoders from other brands, provide the brand and model information for equivalent replacement suggestions. |
| 2 | Choose the encoder type: Incremental, Absolute, Draw Wire Sensors, or Manual Pulse Generator. |
| 3 | Select the output format (for incremental: NPN/PNP/LINE DRIVER/PUSH PULL) or the interface (e.g., Modbus, SSI, BISS, etc.). |
| 4 | Choose the encoder resolution (Incremental: up to 50000 ppr; Absolute: up to 29-bit). |
| 5 | Select the housing diameter and shaft diameter of the encoder. |
10. Equivalent Replacement Products Reference
| Brand | Example Models |
|---|---|
| Omron | E6A2-CS3C, E6A2-CS3E, E6A2-CS5C, E6A2-CW3C, E6A2-CW3E, E6A2-CW5C, E6A2-CWZ3C, E6A2-CWZ3E, E6A2-CWZ5C |
| Koyo | TRD-MX, TRD-2E/1EH, TRD-2T, TRD-2TH, TRD-S, TRD-SH, TRD-N, TRD-NH, TRD-J, TRD-GK, TRD-CH Series |
| Autonics | E30S, E40S, E40H, E50S, E50H, E60S, E60H |
11. Packaging Details
| Item | Description |
|---|---|
| Packaging | Standard export packaging or customized per buyer's requirements |
12. FAQ and Other Information
| Content | Details |
|---|---|
| Delivery Time | Shipment within one week via DHL or other specified logistics after full payment |
| Payment Methods | Bank Transfer, Western Union, Paypal |
| Quality Control | Inspected by a professional quality control team with over 10 years of experience |
| Technical Support | Supported by a professional technical team, including protocols such as Profinet, EtherCAT, Modbus-TCP, and Powerlink |
| Certifications | CE, ISO9001, RoHS; KC certification in progress |
| After-sales Policy | 1-year warranty and lifetime technical support |
| Contact | [email protected] (also available via WhatsApp or WeChat for instant messaging) |



