High Quality Water Meter Transmitter

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. Product Application Overview
ACITEK G100-DO is a miniature DIN rail-mounted dissolved oxygen (DO) transmitter specially designed for industrial process water quality monitoring. With an ultra-narrow 12.5 mm modular housing, 4–20 mA active analog output, RS485 communication, 24 VDC power supply and integrated temperature measurement function, it perfectly solves the installation limitation of narrow control cabinets, compact fermenters and small-scale process monitoring stations. Matched with 12 mm diameter 316L stainless steel DO sensor (IP65 protection), it delivers fast response within 1 minute and stable long-term measurement, widely deployed in chemical, pharmaceutical, biotechnology, food & beverage, energy industries, industrial wastewater treatment and laboratory process analysis. The complete package includes DIN rail transmitter, stainless steel DO sensor, mounting fittings, signal cable, flow cell and operation manual, supporting OEM & ODM customized service for diversified on-site working conditionsacitekinst....

2. Industry-Specific Application Scenarios
2.1 Biotechnology & Pharmaceutical Fermentation
Biopharmaceutical and microbial fermentation processes require precise real-time dissolved oxygen control to guarantee strain reproduction, metabolite yield and drug purity.


Core application: Small & medium-sized bioreactors, seed culture tanks, cell culture lines.
Application advantages:

Ultra-thin 12.5 mm body allows centralized installation in dense PLC control cabinets with multi-channel parameter transmitters (pH, conductivity, DO) without cabinet space shortage.
Built-in manual calibration keys (K3/K4) support on-site one-point/two-point calibration without extra handheld calibrators; calibration cycle is recommended once every 3 months to sustain measurement accuracy.
Stainless steel 1.4435 sensor probe adapts to repeated SIP/CIP high-temperature sterilization sanitary working conditions, avoiding corrosion from culture medium and organic solvents.
4–20 mA signal connects to DCS/PLC to realize automatic linkage of stirring speed and aeration flow, stabilizing DO concentration in fermentation broth and improving production batch consistency.


Typical case: Antibiotic, amino acid, vaccine cell culture production lines.

2.2 Food & Beverage Production
Dissolved oxygen directly determines product flavor, shelf life and oxidation stability in food processing.


Core application: Beer/wine fermentation, pure water production, beverage filling pretreatment, dairy processing.
Working value:

Monitor low-level residual oxygen in finished water and beverage pipelines to suppress fat oxidation, color fading and flavor deterioration.
Fermentation tank online monitoring: control oxygen supply in yeast growth stage to avoid excessive DO causing off-flavor in finished wine.
Compact DIN rail design fits small beverage factory central control cabinets, realizing multi-point DO monitoring for multiple production lines with low overall investment cost.


Matching hardware: 12 mm stainless steel sanitary DO sensor with silicone sealing, compatible with food-grade fluid pipelines.

2.3 Chemical Industry Process Monitoring
Chemical synthesis, polymerization and fine chemical reactions are sensitive to dissolved oxygen to prevent invalid oxidation side reactions.


Application points: Chemical reaction kettles, solvent recovery systems, intermediate water circulation pipelines, fine chemical pilot test lines.
Product highlights for chemical sites:

4-wire system with 14–24 VDC wide voltage power supply, stable signal transmission under factory electromagnetic interference.
RS485 Modbus communication supports distributed networking, enabling centralized remote data collection of dozens of monitoring points.
Low-cost modular measurement station solution, ideal for small-batch pilot chemical workshops with limited cabinet space.



2.4 Energy & Power Industry Water Treatment
High dissolved oxygen in boiler feed water, cooling circulating water and thermal power sampling water will cause pipeline and equipment corrosion, shortening service life.


Core scenario: Thermal power plant condensate sampling rack, boiler deaerator outlet monitoring, cooling water circulation system.
On-site advantages:

Slim DIN rail transmitter can be densely arranged on sampling rack small-sized control boxes.
Synchronous measurement of dissolved oxygen and medium temperature, providing dual-parameter data for water chemical supervision.
4–20 mA analog signal uploads DO data to power plant monitoring system to trigger deaeration equipment linkage control.



2.5 Industrial Wastewater & Environmental Water Treatment
Aerobic and anaerobic biochemical tanks rely on precise DO adjustment to optimize activated sludge treatment efficiency and reduce aeration energy consumption.


Applications: Factory sewage treatment stations, small municipal wastewater aerobic tanks, discharge water quality monitoring wells.
Field performance:

IP65 stainless steel sensor probe resists sludge adhesion and weak corrosive wastewater medium.
Fast 1-minute response time timely reflects DO fluctuation in biochemical tanks to adjust fan operation frequency and cut power consumption.
Low maintenance cost, suitable for scattered small sewage treatment stations with limited operation manpower.



2.6 Laboratory & Pilot Test Equipment
Universities, R&D laboratories and pilot workshops have compact test equipment with limited installation space.


Usage scene: Laboratory bench bioreactors, small water quality test circulation devices, material oxidation test systems.
Laboratory advantages: Miniature transmitter saves laboratory control box space; simple manual calibration operation meets frequent experimental parameter calibration demands; one-year warranty and customizable OEM labels support laboratory self-developed test equipment matching.

3. Installation & System Application Modes
3.1 DIN Rail Central Cabinet Installation
The G100-DO transmitter adopts standard 35 mm DIN rail mounting, dozens of units can be side-by-side installed together with pH, conductivity transmitters inside narrow control cabinets, realizing multi-parameter centralized monitoring of the whole production line, which is the most mainstream application mode for medium and small factories.

3.2 Independent Small-Scale Monitoring Station
Matched with flow chamber, mounting bracket and cable, it forms a complete compact DO measuring station for single reactor, single pipeline or single wastewater tank independent monitoring, without large integrated analysis cabinet, greatly reducing equipment procurement and cabinet transformation cost.

3.3 PLC/DCS Automatic Control System Integration

Analog output: 4–20 mA active current signal accesses PLC analog module to realize closed-loop automatic control of aeration, stirring, deaeration equipment.
Digital communication: RS485 Modbus-RTU connects to industrial gateway, uploading DO & temperature data to upper computer, SCADA or cloud platform for remote real-time viewing and historical data recording.

4. Application Advantages Over Traditional Large DO Transmitters

Space-saving layout: Only 12.5 mm width, solving the installation bottleneck of narrow cabinets and compact equipment that large display transmitters cannot fit.
Cost-effective construction: Low unit price plus modular assembly reduces the total investment of multi-point monitoring stations, especially suitable for small factories and pilot projects.
Wide universal compatibility: One set of equipment covers biotech, food, chemical, energy and environmental protection industries; stainless steel sensor adapts to sanitary, corrosive and aqueous working conditions.
Easy on-site maintenance: Independent K3/K4 calibration buttons support field calibration without removing the transmitter from the cabinet; recommended quarterly calibration ensures long-term stable measurement.
Dual signal output: Simultaneous 4–20 mA analog and RS485 digital communication, compatible with both traditional PLC control and modern industrial internet remote monitoring systems.

5. Application Matching Notes

For sanitary fermentation and food production, select 1.4435 stainless steel sanitary DO sensor; for chemical wastewater, 316L stainless steel probe is recommended.
The transmitter body protection grade is IP20, so it must be installed inside closed control cabinets; the matched DO sensor reaches IP65 and can be directly inserted into pipelines or tanks.
Power supply range: 14–24 VDC 4-wire connection, avoid long-distance thin wire power supply to prevent voltage drop affecting measurement stability.
OEM/ODM customization is available for special industrial application requirements, including logo printing, cable length adjustment and flow chamber modification.

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.