1. Product Overview
The INK318 is a compact, submersible online chlorophyll-a sensor designed for continuous water quality monitoring in environmental, industrial, and aquatic applications. It employs fluorescence spectroscopy to directly measure chlorophyll-a concentrations in water, eliminating the need for reagents, electrolytes, or frequent maintenance.
Built with a corrosion-resistant titanium housing and IP68 ingress protection, the sensor supports long-term submersion up to 30 meters. It features digital RS-485 communication with MODBUS RTU protocol for seamless integration into industrial control systems, delivering real-time, factory-calibrated data for algae bloom early warning, water quality assessment, and ecological research.
2. Sensing Technology & Self-Cleaning System
2.1 Sensing Technology
The sensor uses fluorescence-based optical measurement:
- Excitation: A high-energy LED emits light at the characteristic absorption wavelength of chlorophyll-a molecules.
- Fluorescence Emission: Chlorophyll-a absorbs the light energy and re-emits fluorescence at a longer, specific wavelength.
- Detection & Conversion: A photodetector captures the emitted fluorescence signal, which is processed by the on-board microcontroller using factory-calibrated algorithms to calculate chlorophyll-a concentration.
- Compensation: Built-in signal processing filters out background noise and temperature drift, ensuring stable readings across the full operating range.
This technology eliminates polarization and reagent-related errors, delivering reliable, repeatable measurements without consumables.
2.2 Self-Cleaning System
The INK318 does not include a built-in automatic self-cleaning system (ultrasonic/mechanical). The standard package does not include a cleaning brush, meaning the optical window must be cleaned manually in turbid or fouling-prone environments to maintain measurement accuracy. Optional cleaning accessories are available separately.
3. Key Features & Competitive Advantages
Key Features
- Reagent-Free Fluorescence Measurement: No electrolytes or chemical additives required, reducing operating costs.
- Wide Range & High Precision: Measures 0–500 µg/L with ±5% accuracy (or ±0.5 µg/L, whichever is greater) and 0.01 µg/L resolution.
- Industrial Digital Communication: RS-485 interface with MODBUS RTU for multi-drop network integration.
- Robust Sapphire Optical Window: Ensures durability and chemical resistance in harsh aquatic environments.
- Low Power Consumption: 0.2W power draw under DC 12–24V, ideal for remote solar/battery-powered stations.
- Factory Pre-Calibrated: Calibration data stored on-board, enabling plug-and-play installation.
- Titanium Housing & IP68 Rating: Corrosion-resistant construction suitable for marine and coastal applications.
- Flexible Calibration Options: Supports zero-point, one-point, or two-point calibration for on-site adjustment.
Competitive Advantages
| Aspect |
Advantage Over Alternatives |
| Maintenance Cost |
No reagents required, and low calibration frequency reduces long-term operating costs vs. wet-chemistry sensors. |
| Reliability |
Sapphire optics and titanium housing offer superior durability compared to plastic or glass-based sensors. |
| Integration |
Standard MODBUS protocol enables easy connection to PLC/SCADA systems without additional hardware. |
| Deployment Flexibility |
Compact Φ22mm form factor supports installation in narrow wells, pipes, and portable monitoring setups. |
| Environmental Adaptability |
High anti-interference performance reduces the impact of turbidity and background light on readings. |
4. Technical Specifications
| Parameter |
Specification |
| Model |
INK318 (Y515-A) |
| Measured Parameter |
Chlorophyll-a |
| Measurement Principle |
Fluorescence method |
| Measuring Range |
0–500 µg/L |
| Accuracy |
±5% of reading or ±0.5 µg/L (whichever is greater) |
| Resolution |
0.01 µg/L |
| Operating Temperature Range |
0–50°C |
| Maximum Water Depth |
30 m |
| IP Rating |
IP68 |
| Communication Interface |
RS-485, MODBUS RTU |
| Power Supply |
DC 12–24V |
| Power Consumption |
0.2W (current ≤ 50mA) |
| Housing Material |
Titanium (Ti) |
| Dimensions |
Φ22 mm × 175.5 mm |
| Standard Cable Length |
10 m (customizable) |
| Calibration Method |
Zero-point, one-point, or two-point calibration |
| Optical Window Material |
Sapphire |
| Anti-Interference Performance |
High resistance to turbidity and background light |
5. Applications
The INK318 is suitable for a wide range of water quality monitoring applications:
- Surface Water Monitoring: Rivers, lakes, reservoirs, and watershed assessment.
- Drinking Water Source Protection: Algae bloom early warning in intake water sources.
- Coastal & Marine Monitoring: Seawater quality, eutrophication, and red tide detection.
- Aquaculture: Fish/shrimp farm water quality control to prevent oxygen depletion.
- Industrial Wastewater: Discharge monitoring and process water quality control.
- Environmental Research: Ecological surveys, eutrophication studies, and long-term monitoring.
- Reservoir & Dam Management: Real-time water quality monitoring for large-scale water bodies.
- Desalination Plants: Intake water quality monitoring to protect reverse osmosis systems.
