ER Probe Corrosion Monitoring Meter CST400C

The CST400C Electric Resistance Probe Corrosion Monitoring Meter is designed for onsite corrosion monitoring of pipes and vessels delivering gas, water, oil and multi-phase fluids, providing data such as corrosion rate, amount of corrosion, and corrosion allowance. It employs high-speed, low-power MCU and high-precision, low-power 24-bit ADC with resolution up to 0.06/1,000,000. Thanks to AC excitation source technology and AV bridge principles, it can achieve high-resolution micro-resistance measurement, with corrosion resolution reaching 0.01% of the sensing element's lifespan. Built-in temperature compensation circuit minimizes the impact of temperature fluctuations on results.

Figure 1. CST400C

The CST400C uses industrial-grade components and an IP67-rated enclosure, with all interfaces designed to be waterproof for field work. It complies with GB3836.1-2011 Electrical apparatus for explosive gas atmospheres Part 1: General requirements and GB3836.4-2011 Explosion-proof electrical apparatus for explosive atmospheres - Part 4 - Equipment with intrinsic safety “I” protection. The explosion-proof grade is Exib Ⅱ CT4, which is suitable for Zone 1, Zone 2, T1-T4 places with explosive gas mixtures; it has passed the inspection from the National Explosion-proof Electrical Products Quality Inspection Center and obtained the explosion-proof certificate.

Figure 2. CST400C installation site

CST400C adopts RS485 communication. CST620 handheld datalogger can be used to manually download data in local place. Data can also be transmitted to the terminal's control center through a wired network formed by communication cables, or via CST610 wireless data transceiver with a commercial wireless network. The Modbus protocol or user-specified protocol can also be used to connect the corrosion monitoring data to the user's comprehensive data management platform.

The corrosion analysis software enables real-time monitoring of corrosion status. With a built-in high-precision real-time calendar clock, the instrument can timestamp each data point. Power supply options include large-capacity lithium battery supporting over 400 days of operation, or DC12V. Solar power systems or conversion from 220V mains electricity to DC12V are also feasible.

Specifications

Software Features

The corrosion analysis software is used under Windows XP or above. The data can be directly imported into the computer for data processing &analysis through CST620. Software key modules include corrosion data management, corrosion allowance & corrosion rate display, graph printing, language switching, data processing &analysis. Based on the differential calculation (linear regression) of the corrosion thinning amount, the software can obtain the corrosion rate, corrosion allowance and corrosion loss during any period, and calculate the corrosion rate, draw the corrosion curve, and export the data analysis report. The software supports switching between Chinese and English. All data and graphics are importable, exportable, and printable.

Figure 3. Online corrosion analysis software

Application

Monitoring of metal's total corrosion amount, corrosion allowance and corrosion rate in gas, liquid and oil-water-gas multiphase systems

Instrument Configuration

① CST400C Resistance Probe Corrosion Monitoring meter

② CP-41 Resistance Probe

③ Probe installation device

④ Pressurized retrieval device (optional)

⑤ CSkit corrosion analysis software or Modbus protocol

⑥ CST620 handheld datalogger for manual data download (optional)

⑦ CST610 wireless data transceiver for remote monitoring network setup (optional)

Remote Corrosion Monitoring Network System

A remote monitoring network system can be established using commercial 4G networks, where one or more CST610 wireless transceivers act as RTU nodes for periodic polling of CST400C instruments, and transmit data in real-time to the central control center. Monitoring software visually displays test data from various devices, including remaining thickness and corrosion rates.

Figure 4. Remote corrosion monitoring network

In environments where wireless network is unavailable for safety reasons, the user can build an intrinsically safe wired network based on RS485 to transmit data to the terminal control center via a communication cable, or directly use CST620 handheld data logger for manual download.