YOKOGAWA SC200S Control Valve Positioner

YOKOGAWA SC200S Control Valve Positioner

Core product positioning and application scenarios

YOKOGAWA SC200S is a 2-wire conductivity/resistivity measurement system designed specifically for industrial automation process control. Its core function is to monitor the conductivity performance of industrial process media in real time, providing accurate data support for process optimization, quality control, and safety assurance. Its typical application scenarios include: monitoring of solution reaction processes in the chemical industry, testing of boiler feedwater quality in the power industry, monitoring of purified water purity in the pharmaceutical industry, and analysis of raw material water quality in the food and beverage industry, which are sensitive to the conductivity characteristics of the medium. As a two-wire instrument, it has the advantage of low-power design and can be directly connected to the industrial standard 4-20mA signal circuit. It is seamlessly compatible with Yokogawa Electric's DCS system or other mainstream industrial control systems, achieving long-distance transmission and centralized control of measurement data.

Key technical parameters

The technical parameters of SC200S are designed around the stable operation requirements of industrial sites, and the core indicators are as follows:

-Power supply specifications: Adopting a 2-wire circuit power supply, compatible with industrial standard 24V DC power supply system, the power supply voltage range is suitable for most industrial power supply environments, ensuring stable operation with small voltage fluctuations.

-Measurement range: Conductivity measurement covers the requirements of conventional industrial scenarios, and the specific range can be adjusted through matching sensor parameter configuration to meet the measurement needs of different concentration media; The accuracy of resistivity measurement meets the monitoring requirements of medium to high purity media, providing reliable data for precision industrial production.

-Output signal: Standard 4-20mA analog signal output, with a signal transmission distance of over 1000 meters (depending on cable specifications), can be directly connected to display instruments, recorders, or AI modules of DCS systems to achieve real-time acquisition and feedback of measurement data.

-Environmental adaptability: The working temperature range is -20 ℃ to 60 ℃ (-4 ℉ to 140 ℉), with a relative humidity tolerance of 95% (non condensing state), which can adapt to the temperature and humidity environment of most industrial sites; The protection level of the shell meets the requirements of dust and splash prevention in industrial sites, and can resist the erosion of general industrial dust and occasional water droplets.

-Frequency response: In response to the dynamic characteristics of industrial media, the frequency response capability of signal processing has been optimized to quickly capture sudden changes in the conductivity of the media. The response time meets the real-time requirements of conventional industrial process control and avoids process deviations caused by measurement delays.

Core functional features

1. High precision measurement and stable operation design

The SC200S adopts Yokogawa Electric's self-developed signal conditioning algorithm, which can effectively suppress electromagnetic interference in industrial sites (such as clutter signals generated by frequency converters, motors, and other equipment), ensuring the stability and accuracy of measurement data. The instrument is equipped with a built-in self diagnostic function, which can monitor its own circuit status, sensor connection status, and signal transmission link in real time. When a fault occurs, it can be fed back to the control system through abnormal signals, making it easy for operation and maintenance personnel to troubleshoot problems in a timely manner and reduce the risk of equipment shutdown.

2. Convenient installation and maintenance design

The instrument adopts a modular structure design, and the installation method supports wall mounted or pipe mounted (suitable for on-site installation environment). The installation steps are simple and do not require complex professional tools. Sensors and instrument bodies are connected through standardized interfaces for easy on-site replacement and calibration; The design of the instrument casing takes into account both protection and convenience. The layout of key debugging knobs and wiring terminals is reasonable, and operation and maintenance personnel can complete parameter adjustments and line inspections without disassembling the entire casing, reducing maintenance workload.

3. Good system compatibility and scalability

As a member of the Yokogawa Electric Process Analysis Instrument family, SC200S can form a collaborative working mode with Yokogawa WT series power analyzers, DCS systems, and other products. At the same time, it follows the communication and signal standards commonly used in industry and is compatible with other brands of industrial control equipment. In addition, the instrument supports regular calibration through external calibration equipment to ensure stable measurement accuracy during long-term operation and extend the service life of the equipment.

Important safety regulations and usage precautions

As an industrial electrical equipment, the safe operation of SC200S is directly related to personnel safety and equipment stability. The following safety regulations must be strictly followed (some clauses refer to Yokogawa Electric's General Safety Standards for Industrial Instruments):

1. Electrical safety operation specifications

-Warning: Before connecting to the power supply, it is necessary to confirm that the power supply voltage matches the rated voltage of the instrument, in order to avoid excessive voltage that may cause the internal circuit of the instrument to burn out, leading to fire or electric shock accidents.

-The protective grounding terminal must be reliably connected, and it is strictly prohibited to cut off or disconnect the protective grounding wire, otherwise the electric shock protection function of the instrument will be lost, increasing the risk of electric shock for operators. Before connecting the instrument to the measuring medium or external control system, the protective grounding connection should be completed first.

-The measurement category of the instrument is other category (O), and it is strictly prohibited to use it in CAT II, III, IV measurement scenarios (such as direct measurement of power grid lines, high-voltage equipment, etc.). Regardless of the measurement category of the supporting measuring instrument, this restriction must be followed to avoid short circuits or electric shock accidents caused by insufficient insulation level.

-If damage is found to the instrument casing or cables, they should be immediately stopped from use to avoid electric shock or short circuit caused by exposed internal circuits; During the operation, it is necessary to avoid stepping on or squeezing the instrument cable to prevent damage to the cable sheath from affecting the insulation performance.

2. Installation and environmental safety requirements

-It is strictly prohibited to install or operate instruments in explosive atmospheres, flammable liquids, or steam environments where equipment operation may cause fire or explosion accidents.

-The installation location should be away from hot objects to avoid excessive temperature caused by environmental heat, which may affect measurement accuracy or damage internal components; If multiple instruments are installed side by side, a minimum installation distance of 10mm should be maintained between main units, sub units, and between main/sub units of different groups of instruments to ensure smooth heat dissipation.

-When using installation screws to fix the main unit, M4 screws with protruding fixtures ranging from 5.5mm to 8.0mm should be selected. If the screw length is too long, it may penetrate the housing and damage the internal circuit. If it is too short, the fixing strength may be insufficient, and the instrument may fall off and cause damage.

3. Operation and maintenance safety regulations

-Only operators with professional knowledge are allowed to operate the instrument. Before operation, it is necessary to carefully read the product manual and familiarize oneself with the instrument functions and operating procedures; As an integral part of the instrument, the manual should be properly stored in a safe location near the instrument for easy reference at any time until the instrument is discarded.

-Non Yokogawa Electric professionals are strictly prohibited from disassembling and assembling instruments. There are high-voltage circuits in some areas inside the instruments, and unauthorized disassembly may result in electric shock, instrument damage, or fire accidents.

-Before connecting or disconnecting the instrument from the measured medium, the measured current system or related process equipment must be turned off to avoid electric shock or short circuit accidents caused by live operation.

-If the instrument power indicator light (green) still goes out after power supply, stop using it immediately and contact the nearest Yokogawa Electric dealer or professional maintenance personnel for handling. Do not disassemble and repair it yourself.