# AGRINOVO-PH-100: Digital pH Sensor

Agrinovo technical datasheet, revision 1.2 (October 2026).
PDF version: https://agrinovo.io/datasheets/sensors/AGRINOVO-PH-100_Datasheet.pdf

## 1. Overview

The AGRINOVO-PH-100 is a digital pH sensor for continuous water quality monitoring. It provides high-accuracy pH measurements through RS485 Modbus-RTU interface with three-point calibration capability.

### Key Features

- pH range: 0 to 14.00
- Resolution: 0.01 pH
- Accuracy: ±0.02 pH
- Stability: ≤0.02 pH/24h
- 3-point calibration
- RS485 Modbus-RTU
- Low power: ≤0.5W
- 12-24 VDC supply

### Applications

- Agricultural irrigation
- Hydroponics and greenhouses
- Water quality testing
- Aquaculture
- Wastewater treatment

## 2. Specifications

| Parameter | Specification |
|:----------|:--------------|
| **Measurement Range** | 0.00 to 14.00 pH |
| **Resolution** | 0.01 pH |
| **Accuracy** | ±0.02 pH |
| **Stability** | ≤0.02 pH / 24 hours |
| **Power Consumption** | ≤0.5W |
| **Supply Voltage** | 12-24 VDC |
| **Operating Temp** | 0 to 60°C |

## 3. Wiring

| Wire Color | Function | Description |
|:-----------|:---------|:------------|
| **Red** | V+ | Power Supply (12-24V DC) |
| **Black** | GND | Power Ground |
| **Yellow** | RS485-A | Data+ |
| **Green** | RS485-B | Data- |

## 4. Communication Settings

| Parameter | Value |
|:----------|:------|
| **Protocol** | Modbus-RTU |
| **Baud Rate** | 9600 bps |
| **Data Bits** | 8 |
| **Parity** | None |
| **Stop Bits** | 1 |
| **Default Address** | 0x01 |

## 5. Register Map

### Measurement Registers (Function 0x03)

| Address | Description | Scaling |
|:--------|:------------|:--------|
| 0x0000 | pH Value | Value ÷ 100 |

### Configuration Registers (Function 0x06)

| Address | Description | Notes |
|:--------|:------------|:------|
| 0x0009 | Intercept/Offset | Calibration offset |
| 0x0050 | Slave Address | 0x01 to 0xFE |
| 0x005A | 9.18 pH Calibration | Write 0x000A |
| 0x005B | 6.86 pH Calibration | Write 0x000B |
| 0x005C | 4.00 pH Calibration | Write 0x000C |

## 6. Reading pH Value

Read 1 register from 0x0000:

```
Request:  01 03 00 00 00 01 84 0A
Response: 01 03 02 02 AE 38 98
```

**Decoding:**

| Hex | Decimal | Scaling | Result |
|:----|:--------|:--------|:-------|
| 0x02AE | 686 | ÷100 | **6.86 pH** |

## 7. Three-Point Calibration

Clean electrode with distilled water between each buffer.

| Step | Solution | Register | Command |
|:-----|:---------|:---------|:--------|
| 1 | 9.18 pH | 0x005A | Write 0x000A |
| 2 | 6.86 pH | 0x005B | Write 0x000B |
| 3 | 4.00 pH | 0x005C | Write 0x000C |

### Calibration Commands

**9.18 pH:**
```
01 06 00 5A 00 0A 29 DE
```

**6.86 pH:**
```
01 06 00 5B 00 0B B9 DE
```

**4.00 pH:**
```
01 06 00 5C 00 0C 49 DD
```

### Calibration Procedure

1. Clean electrode with distilled water
2. Place in buffer solution
3. Wait for reading to stabilize
4. Send calibration command
5. Repeat for each buffer

## 8. Address Configuration

### Change Address (0x01 → 0x02)

```
01 06 00 50 00 02 08 1A
```

### Broadcast Discovery

Use address 0xFE with only one device connected.

## 9. Installation Notes

**Safety**

- Do not hot-plug
- Verify wiring before power

**Sensor Care**

- Clean with distilled water
- Avoid air bubbles
- No bare hand contact

## Ordering Information

| Part number | Description |
|:------------|:------------|
| AGRINOVO-PH-100 | Digital pH Sensor |

## Revision History

| Rev | Date | Changes |
|:----|:-----|:--------|
| 1.0 | June 2026 | Initial release |
| 1.1 | August 2026 | Layout revision |
| 1.2 | October 2026 | New layout |

## Contact

Agrinovo, https://agrinovo.io/products, contact@agrinovo.io, +972 54 688 8148 (direct / WhatsApp).
Specifications subject to change without notice.