Causes and countermeasures of false alarms of temperature and humidity monitor WK-D2T(TH)

During the operation of thermal power plants, condensation problems have always been an important hidden danger threatening equipment safety. Condensation may not only cause electrical short circuits and reduced insulation performance, but may also trigger a series of chain reactions such as equipment corrosion and mechanical failure. To meet this challenge, modern thermal power plants generally use intelligent temperature and humidity monitors, such as the dual-channel dual-control temperature and humidity monitor WK-D2T(TH), which monitors the internal environmental parameters of the equipment in real time and warns of condensation risks in a timely manner. However, in actual applications, the monitor may have an abnormal phenomenon of “frequent alarms for condensation but no condensation in reality”, which not only interferes with the judgment of operation and maintenance personnel, but may also cover up the real equipment hidden dangers. This article will deeply explore the potential causes of this problem from multiple perspectives such as technical principles, environmental impacts, equipment characteristics and system interactions, and put forward targeted optimization suggestions.

I. Working principle of the monitor and condensation judgment logic

The core function of the intelligent temperature and humidity monitor is to collect ambient temperature and humidity data through sensors, and combine the algorithm model to determine whether there is a condensation risk. Taking the temperature and humidity monitor WK-D2T (TH) as an example, its condensation alarm mechanism is usually based on the following logic: when the ambient temperature is lower than the dew point temperature, the water vapor in the air will condense into liquid water, thus triggering an alarm. However, this logic depends on the accuracy of the sensor, the rationality of the algorithm model, and the stability of the environmental parameters. If there is a deviation in any link, it may lead to a false alarm.

In the actual environment of a thermal power plant, the temperature and humidity changes in the equipment cavity are often affected by multiple factors, such as equipment start and stop, external meteorological conditions (such as rainfall, high humidity weather), and the operating status of the cooling system. These dynamic changes may cause the real-time data of the monitor to deviate from the actual physical conditions, thereby causing misjudgment.

II. Analysis of potential causes of false alarms

1. Sensor performance and installation issues

The temperature and humidity sensor WK-D2T (TH) is the core component of the monitor, and its performance directly affects the accuracy of the alarm. If the sensor ages, decreases in sensitivity, or fails to calibrate due to long-term operation, it may cause distortion of the collected data. For example, humidity sensors may not be able to truly reflect environmental humidity in high humidity environments due to condensation on the surface or attachment of pollutants; if the temperature sensor is installed in an improper position (such as near a heat source or cold source), it may be misjudged due to excessive local temperature differences. In addition, insufficient sealing of the sensor may also cause it to be damp or corroded, further exacerbating the measurement error.

2. Dynamic interference of environmental parameters

The equipment cavity of a thermal power plant is not a static closed space, and its internal environment is often affected by both external meteorological conditions and the operating status of the equipment. For example, when the equipment is started, the cavity temperature may be temporarily higher than the dew point temperature due to the rapid heating of the heating element. If the algorithm of the temperature and humidity monitor WK-D2T (TH) does not fully consider this transient change, it may be misjudged as “no condensation risk”; conversely, after the equipment is shut down, the cavity temperature may drop rapidly due to heat dissipation, resulting in a relatively high humidity and triggering a false alarm. In addition, abnormalities in the cooling system (such as unstable cooling water flow) may also cause local temperature and humidity fluctuations in the cavity, interfering with the judgment of the monitor.

3. Limitations of the algorithm model

The condensation determination algorithm of the temperature and humidity meter WK-D2T(TH) is usually based on a static dew point temperature calculation model, and does not fully consider the nonlinear changes in dynamic environments. For example, the calculation of the dew point temperature assumes that the air humidity is evenly distributed, but in the actual equipment cavity, there may be local high humidity areas (such as ventilation dead corners or places where condensation water is not discharged smoothly). If the algorithm is not optimized for such scenarios, local anomalies may be misjudged as overall condensation risks. In addition, the algorithm’s dependence on historical data may also lead to false alarms. For example, if the monitor continuously collects multiple critical value data in a short period of time, the alarm may be triggered frequently due to unreasonable threshold settings.

4. System integration and signal interference

In complex industrial environments, the integration of monitors with other devices (such as PLC and DCS systems) may introduce signal interference problems. For example, electromagnetic interference may affect the communication signal of the sensor, resulting in data transmission errors; power supply fluctuations or poor grounding may also cause malfunctions of the monitor. In addition, if the software design of the monitor does not fully consider the compatibility of multi-device collaborative operation, false alarms may be generated due to protocol conflicts or data parsing errors.

5. Human operation and maintenance omissions

In the daily operation and maintenance of the thermometer WK-D2T (TH), the standardization of human operation may also affect the accuracy of the alarm. For example, if the operation and maintenance personnel fail to calibrate the sensor regularly according to the regulations, or fail to clean the contaminants on the sensor surface in time, the measured data may deviate from the actual value. In addition, if the parameter settings of the thermometer are not optimized according to the specific equipment environment, it may also lead to misjudgment. For example, if the condensation alarm threshold is set too low, the alarm may be triggered frequently when the ambient humidity fluctuates slightly, while a threshold that is too high may delay the real risk warning.

The intelligent temperature and humidity monitor WK-D2T (TH) plays an indispensable role in the safe operation of thermal power plants, but the accuracy of its alarm depends on the coordinated optimization of hardware performance, algorithm design and operation and maintenance management. For the problem of “frequent alarms for condensation but no condensation in reality”, it is necessary to start from the technical principles, systematically analyze the causes, and continuously iterate and improve through engineering practice. Only in this way can we truly achieve accurate early warning of condensation risks and safeguard the stable operation of thermal power plants.

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E-mail: sales@yoyik.com
Tel: +86-838-2226655
Whatsapp: +86-13618105229

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