ACITEK's Water Transmitter

In today's society, water is a basic substance for human life and economic development, and its importance is self-evident. From daily drinking to industrial production and agricultural irrigation, the quality of water is directly related to people's health and sustainable development of the industry. The water quality monitoring industry has also shouldered a heavy responsibility and become a key line of defense to protect the safety of water resources. ​
However, the rapid development of modern social economy is bringing many difficult problems to water quality monitoring. On the one hand, emerging pollutants continue to emerge, such as microplastics and drug residues, and traditional monitoring technology is difficult to capture their traces, and it is urgent to develop new detection methods. On the other hand, with the expansion of cities and changes in industrial layout, the scientific nature of the layout of water quality monitoring points has been challenged, and some areas have insufficient monitoring coverage, which cannot timely and comprehensively reflect the dynamics of water quality. ​
Faced with these challenges, the industry actively explores innovative paths. In the field of technological innovation, scientific research teams have increased investment to develop monitoring equipment based on cutting-edge technologies such as nanotechnology and biosensors, greatly improving the detection accuracy and efficiency of trace pollutants. At the same time, with the help of Internet of Things technology, an intelligent monitoring network is built to realize real-time transmission and analysis of monitoring data, effectively make up for the shortcomings of insufficient monitoring points, improve the overall monitoring efficiency, provide solid support for the scientific management of water resources, and ensure that high-quality water sources continue to benefit society.

In recent years, with the continuous improvement of water quality management technology and level in water plants, online water quality monitoring system has been integrated as an emerging management method, triggering industry changes. With the help of advanced sensor technology and automation equipment, the system can monitor the quality of raw water, water production process and outgoing water in water plants 24 hours a day. From key indicators such as pH, turbidity to residual chlorine content, they can all be accurately measured, and data can be fed back in real time, which completely changes the lag and limitations of traditional manual sampling and monitoring. ​
After the online monitoring system is put into use, the water plant can capture subtle changes in water quality in a timely manner, quickly adjust the water production process, and ensure that the water quality is stable and meets the standards. This not only effectively improves the safety of water supply and ensures the health of residents' water use, but also greatly improves the operating efficiency of water plants and reduces labor costs and management difficulties. At present, the online water quality monitoring system has become an important measure for many water plants to optimize management. With the continuous iteration of technology, it is expected to be popularized in more water plants in the future, promoting the entire water supply industry to move towards intelligent and refined management, and building a solid line of defe

Drinking water safety is clearly a critical priority.Yet the number of threats to water safety continues to grow daily, and include animal and human waste, improper disposal of chemicals, pesticides, and deep earth injection of hazardous materials. Contamination is also a threat due to improper water treatment and disinfection procedures, as well as from poorly maintained water distribution systems.

The Safe Drinking Water Act, has established national health-based standards that address both man-made and naturally occurring contamination. Compliance requires consistent, accurate measurement of water parameters performed in the lab, field, and online. While many measurements can be made in the lab, key variables such as pH, conductivity, fluoride, and chlorine can also be measured online in real-time to warn immediately if limits are exceeded.

Usually there is four steps for drinking water process
First step is Pre-treatment for source water
Second step is Filtration
Third step is disinfection process
Fourth step is distribution ,we have to measure pH,turbidity,hardness,residual chlorine,conductivity(TDS),then we can know the potential risks or threaten to public heath on time.the residual chlorine value should be over 0.3mg/L when be piped out from drinking water plant, and over 0.05mg/L at end of pipe network.turbidity must less 1NTU,pH value is between 6.5~8,5,pipe will be corrosive if pH value is less 6.5pH and easy scale if pH is over 8.5pH.

At present online water quality monitoring system can monitor water quality 24 hours and real time.it also provide quickly and correct information to decision-makers based on water quality changes in real time,Thereby providing people with healthy and safe water quality.

1. Project Background
A medium-sized biopharmaceutical manufacturer in Jiangsu runs a full-process purified water system, including multi-media filtration, activated carbon filter, two-stage RO reverse osmosis, mixed ion exchange bed and finished water storage tank. Purified water is used for reagent preparation, equipment cleaning and injection auxiliary production, requiring stable conductivity ≤ 2.0 μS/cm (25°C) to meet GMP standards.

Original Monitoring Pain Points

Adopted old 2-wire conductivity controllers, severe measurement polarization error under low conductivity; readings fluctuated ±0.5~1.2 μS/cm, unable to judge resin failure accurately.
Only single 4-20mA conductivity output, no independent temperature signal; PLC could not realize automatic temperature compensation logic.
Single relay output only supports simple high-limit alarm, cannot interlock resin regeneration pump and RO bypass valve synchronously.
No intelligent sensor diagnosis function; electrode fouling or cable aging could not be pre-warned, leading to long-time unqualified water without discovery.
Single panel mounting mode, difficult to install beside vertical ion exchange tanks, extra bracket costs required.

Project Demand

Stable low-conductivity detection for RO & mixed bed outlet, eliminate polarization error
Dual independent 4-20mA outputs for conductivity + temperature synchronous transmission
Dual floating relays for automatic linkage of regeneration and bypass protection
Multi-installation modes: wall / pipe / panel mounting to fit all process points
Built-in sensor monitoring & preventive maintenance reminder function
Compatible with all analog two-electrode platinum probes (ACITEK CR-GS-10 K=10)

2. Solution Deployment
The factory fully replaced old controllers with ACITEK G400-COND 4-wire conductivity transmitters, matching CR-GS-10 platinum two-electrode sensors, complete system layout as below:

2.1 Equipment Configuration

Transmitter: ACITEK G400-COND, 4-wire signal acquisition, PBT reinforced industrial enclosure, 24VDC power supply;
Matching electrode: CR-GS-10 platinum conductivity probe, cell constant K=10, installed via G1/2 pipeline thread;
Signal design:

Channel 1 4-20mA: Conductivity value (0–20 μS/cm customized range for purified water)
Channel 2 4-20mA: Real-time water temperature (0–60°C)
Relay 1: High conductivity alarm, trigger mixed bed acid-alkali regeneration pump
Relay 2: Ultra-high conductivity interlock, open RO bypass valve to drain unqualified water


Installation layout:

RO front/back monitoring points: Panel mounting inside control cabinet
Ion exchange tank outlet: Pipe wall mounting with matching hoop accessories
Finished water pipeline: Wall-mounted beside flow cell


Calibration: On-site one-point solution calibration, support one-key factory reset for routine maintenance.

2.2 Core Technical Matching Advantages of G400-COND

4-wire measurement anti-polarization technology Separate current excitation and signal collecting circuit, completely eliminate ion polarization interference in low-ion purified water, stable reading fluctuation controlled within ±0.08 μS/cm, fully meet pharmaceutical water precision requirements.
Dual independent 4-20mA current outputs Conductivity and temperature transmit signals separately to workshop PLC, realizing automatic 25℃ benchmark temperature compensation program, no manual parameter modification needed when water temperature changes in workshop.
Dual floating relay contacts for multi-linkage control Two groups of independent relays realize graded control: early warning regeneration & emergency bypass, avoid mass unqualified purified water entering production line, reduce waste loss.
Multi-scene flexible installation Support panel, wall and pipe three installation ways, no customized bracket required for vertical tank measuring points, cut on-site installation material and labor cost by 30%.
Intelligent sensor continuous monitoring & maintenance prompt Real-time judge electrode fouling, cable open/short circuit, pop up maintenance icon on high-contrast LCD screen; technicians can schedule cleaning and calibration in advance, avoid blind sampling inspection.
Wide adaptable cell constant range Freely set cell constant 0.005 ~ 20 cm⁻¹, compatible all existing two-electrode and four-electrode analog sensors of the factory, no need to replace original probes, save renovation investment.

3. On-Site Operation Effect After 6 Months Running
3.1 Measurement Accuracy & Stability Improvement

Original equipment fluctuation: ±0.5~1.2 μS/cm → G400-COND fluctuation ≤ ±0.08 μS/cm
Early warning time of resin failure advanced by 2–3 hours, avoid delayed regeneration leading to conductivity over-limit.

3.2 Automatic Control Economic Benefits

Purified water waste reduced by 82%: Bypass interlock function automatically cut off unqualified water, monthly loss of discarded water reduced by over 12,000 L.
Regeneration chemical consumption saved by 21%: Accurate conductivity threshold trigger regeneration, reduce redundant acid/alkali dosing frequency.
Labor maintenance cost down 65%: Intelligent diagnosis reduces daily manual sampling frequency from 4 times/day to 1 time/day, maintenance workload greatly relieved.

3.3 Environmental & Compliance Value
Continuous traceable conductivity & temperature data fully meet GMP audit data recording requirements; stable long-term operation without drift passes factory quarterly third-party water quality inspection all times.

Customer Feedback
“The ACITEK G400-COND 4-wire transmitter solved our long-standing unstable low-conductivity measurement problem. Dual signal output and dual relay linkage greatly optimize our purified water automatic control logic, the multi-installation design also simplified our on-site reconstruction work. After half a year of operation, data is stable and maintenance work is significantly reduced, which is a cost-effective upgrade solution for pharmaceutical water systems.” ——Water Treatment Supervisor, Biopharmaceutical Plant

4. Extended Application Cases of G400-COND
Case 2: Electronics Factory Ultra-Pure Water Monitoring
Matched low K=0.01 electrode, monitor EDI outlet ultra-pure water, real-time judge filter element aging, guarantee wafer cleaning water quality, support long-distance cable transmission up to 50m without signal attenuation.

Case 3: Cooling Circulating Water Blowdown Control for Machinery Factory
Set high conductivity threshold linkage blowdown valve, control water salt concentration, reduce fresh water replenishment and scale inhibitor dosage, annual water saving over 10,000 tons.

Case 4: Municipal Drinking Water Ion Exchanger Station
Wall-mounted layout for outdoor equipment room, wide temperature LCD display visible under strong light, one-year warranty reduces after-sales maintenance pressure for municipal engineering integrators.

5. Comprehensive Product Strength Summary Verified by Field Cases

Universal 4-wire anti-polarization measurement, cover full range 0.000 μS/cm ~ 200 mS/cm, adapt ultra-pure water to medium-concentration industrial water;
Dual current output + dual relay multi-linkage function, integrate measurement, display and automatic control into one unit, no extra secondary control module needed;
Three installation modes + dual power supply (24VDC/230VAC), fit cabinet, workshop pipeline and outdoor equipment room;
Intelligent sensor diagnosis + preventive maintenance prompt, lower long-term operation & maintenance cost;
Wide compatible cell constant and temperature sensor (Pt1000/NTC30k), support OEM/ODM customization for water equipment manufacturers;
Industrial PBT corrosion-resistant housing, stable continuous 24h online operation with 12-month global warranty.

6. Conclusion
ACITEK G400-COND 4-wire conductivity transmitter perfectly solves the measurement error, single control signal and single installation pain points of traditional 2-wire controllers. Verified by pharmaceutical purified water, electronic ultra-pure water, industrial circulating water and municipal water treatment projects, it provides integrated display, measurement and automatic linkage control solution for all analog conductivity sensors. For water system integrators, pharmaceutical, electronics and municipal water plants pursuing high precision and low maintenance monitoring, G400-COND is a reliable cost-performance 4-wire conductivity control host.