Selection of the installation site of the rapid temperature change test chamber:
The distance from the adjacent wall can smoothly give full play to the role and characteristics of the environmental test chamber. The long-term temperature of 15 ~ 45 °C and the relative environmental humidity exceeding 86% should be selected. site.
The working temperature of the installation site must not change significantly.
It should be installed on a leveling surface (use a level to determine the level on the road during installation).
It should be installed in a site without sun exposure.
It should be installed in a site with excellent natural ventilation.
It should be installed in areas where flammable materials, explosive products and high-temperature heat sources are eliminated.
It should be installed in a site with less dust.
Install it as close as possible to the switching power supply of the power supply system.
High and low temperature test chamber may encounter a variety of problems in the process of use, the following is a summary of potential faults and their causes from different perspectives:
1. Core system failure
Temperature out of control
Reason: PID control parameters are out of balance, ambient temperature exceeds the design range of the equipment, multi-zone temperature interference.
Case: In a special environment workshop, the external high temperature causes the refrigeration system to overload, resulting in temperature drift.
Humidity is abnormal
Reason: poor water quality of humidification leads to scaling and nozzle blockage, failure of ultrasonic humidifier piezoelectric sheet, and incomplete regeneration of dehumidification desiccant.
Special phenomenon: reverse condensation occurs during high humidity test, resulting in the actual humidity in the box being lower than the set value.
2. Mechanical and structural problems
Air flow is disorganized
Performance: There is a temperature gradient of more than 3℃ in the sample area.
Root cause: the customized sample rack changed the original design air duct and the accumulation of dirt on the centrifugal fan blade led to the destruction of dynamic balance.
sealing failure
New failure: the magnetic force of electromagnetic sealing door decreases at low temperature, and the silicone sealing strip becomes brittle and cracks after-70℃.
3. Electrical and control system
Intelligent control failure
Software level: After firmware upgrade, the temperature dead zone setting error occurs and the historical data overflow causes the program to crash.
Hardware level: SSR solid state relay breakdown causes continuous heating and bus communication is subjected to inverter electromagnetic interference.
Security protection vulnerabilities
Hidden dangers: the synchronous failure of the triple temperature protection relay and the false alarm caused by the expiration of the refrigerant detector calibration.
4. Challenges of special working conditions
Specific temperature shock
Problem: -40℃ to +150℃ rapid conversion of the evaporator weld stress cracking, thermal expansion coefficient difference resulting in the failure of the observation window seal.
Long-term operation attenuation
Performance degradation: after 2000 hours of continuous operation, the compressor valve plate wear leads to a decrease of 15% in refrigeration capacity and drift of ceramic heating tube resistance value.
5. Environmental and maintenance impact
Infrastructure adaptation
Case: The power oscillation of PTC heater caused by the fluctuation of power supply voltage and the water hammer effect of cooling water system damaged the plate heat exchanger.
Preventive maintenance blind spots
Lesson: Ignoring the positive pressure of the box leads to water entering the bearing chamber and biofilm growth and blockage in the condensate discharge pipe.
6. Pain points of emerging technologies
New refrigerant application
Challenges: system oil compatibility problems after R448A replaces R404A, and high pressure sealing problems of subcritical CO₂ refrigeration systems.
IoT integration risks
Fault: The remote control protocol is maliciously attacked, resulting in program tampering and cloud storage failure, resulting in the loss of test evidence chain.
Strategy recommendations
Intelligent diagnosis: configure vibration analyzer to predict the failure of compressor bearing, and use infrared thermal imager to scan the electrical connection points regularly.
Reliability design: key components such as evaporator are made of SUS316L stainless steel to improve corrosion resistance, and redundant temperature control modules are added to the control system.
Maintenance innovation: implement a dynamic maintenance plan based on operating hours, and establish an annual refrigerant purity testing system。
The solutions to these problems need to be analyzed in combination with the specific model of the equipment, the use environment and the maintenance history. It is recommended to establish a collaborative maintenance mechanism including the OEM of the equipment, third-party testing institutions and user technical teams. For key test items, it is recommended to configure a dual-machine hot standby system to ensure the continuity of testing.
(1) Equipment installation and commissioning
On-site service: technical personnel will deliver the goods free of charge and complete the mechanical assembly, electrical wiring and debugging. The debugging parameters shall meet the temperature and humidity, salt spray deposition amount and other indicators in the customer's technical agreement.
Acceptance criteria: provide a third-party measurement report, and unqualified equipment shall be returned or replaced directly. For example, the rain test box shall pass 100% acceptance.
(2) Customer training system
Operation training: covers equipment start and stop, program setting and daily maintenance, customized for different user scenarios such as quality inspection institutions and automobile enterprises.
Deep maintenance training: including fault diagnosis (such as troubleshooting of humidity system in high and low temperature and humidity test chamber) and spare parts replacement to improve customers' independent maintenance ability.
(3) Technical support and response
Instant response: respond to repair demand within 15 minutes, and solve routine faults within 48 hours (negotiate with remote areas).
Remote diagnosis: through video guidance or remote access software, quickly locate the problem (such as abnormal dust concentration in the sand test chamber).
(4) Spare parts supply and maintenance
Make spare parts plan, give priority to the supply of wear and tear parts from cooperative units (such as China Railway Inspection and Certification Center, China Electronics Technology Group), and reduce downtime.
Non-manual damage is free of charge during the warranty period, and paid services are provided after the warranty period with transparent charges.
1. Communicate with manufacturers directly to customize requirements
operating steps :
Requirement submission: clear the test object (such as headlights, batteries, sensors, etc.), test scenario (such as simulated extreme cold wading, high temperature and high pressure spraying) and industry specifications (such as automobile, military, electronics);
Technology docking: provide product parameters (size, weight), environmental conditions (temperature range, impact frequency) and special requirements (such as salt spray superposition test, dynamic Angle adjustment);
Confirmation of the scheme: Based on general standards such as GB, IEC and GJB, and industry specifications such as VW 80101 and ISO 16750, the manufacturer designs customized test procedures and equipment configuration schemes.
2. Adapt to the existing standard framework
Manufacturers can expand or adjust based on the following criteria:
national standards :
GB/T 28046.4-2011: For the climate load test of automotive electrical equipment, the core parameters such as temperature, time and circulation times of ice water impact are defined;
GB/T 2423.1: Environmental test specification for general electrical and electronic products, supporting the design of calibration and verification process.
codes of practice :
VW 80101-2005: Volkswagen Electric Components Test Standard, applicable to the refinement of parameters such as spray pressure and water temperature accuracy;
GMW3172: General Motors global engineering standard, supporting multi-environment composite testing (such as ice water impact + salt spray corrosion);
ISO 16750-4:2006: International common vehicle electrical equipment test framework, compatible with customized cycles (e.g. 100 standard or 200 enhanced).
Third, optimize standards by using manufacturers' technical resources
Flexible parameter adjustment:
Temperature range: standard high temperature range 65~160℃, can be extended to-70℃ to +150℃;
Water splashing system: support flow (3~4L/3S or 80L/min), distance (325±25mm adjustable), nozzle type (gap/matrix) and other customization;
Intelligent control: the PLC system can customize the temperature switching rate (such as 20 seconds to complete the conversion from extreme cold to high temperature), data acquisition frequency and report format.
Function module superposition:
Compatible with multiple test requirements such as waterproof (IPX5-6) and dustproof (IP5X-6X);
Support dynamic Angle spraying (15 ~75 adjustable), salt spray composite test and other complex scene simulation.
4. Ensure compliance through certification and verification
Equipment calibration: the manufacturer provides half-year temperature sensor calibration service, the error is controlled within ±2℃;
Third-party verification: it is recommended to certify the temperature change rate, uniformity and other indicators of customized equipment through quality inspection institutions (such as China Electric Power Research Institute, FAW test site);
Data traceability: The test chamber supports USB export of test logs, which is convenient for quality traceability and standard iteration.
5. Service support and case reference
Technical team: Guangdong Hongzhan cooperates with universities and research institutes to provide whole-process support from demand analysis to standard implementation;
Case library invocation: You can refer to the car company case (such as 800V battery pack IPX9K test, intelligent lamp cold and hot cycle verification) to optimize and customize the standard;
After-sales guarantee: customized equipment enjoys 1 year warranty and 48 hours door-to-door maintenance to ensure the stability of standard implementation.
The Guangdong Hongzhan Dust Test Chamber is primarily used to simulate natural sand and dust environments, testing the dust resistance of various products. In industries such as electronics, automotive, and aerospace, products may face challenges from sand and dust. If a product's dust resistance is inadequate, sand and dust particles can penetrate the equipment, leading to malfunctions, performance degradation, or even damage. Therefore, accurately assessing a product's dust resistance is crucial, and the Guangdong Hongzhan Dust Test Chamber provides a reliable testing platform for companies.
(1) Box structure: combination of robust and durable and sealing
The test chamber is constructed from high-quality stainless steel, which not only provides excellent corrosion resistance and protection against sand and dust erosion but also ensures good sealing to prevent sand and dust leakage, maintaining the stability of the testing environment. The interior is meticulously divided into functional areas such as the sample testing zone, sand and dust circulation duct, heating system, and control system, facilitating both operation and maintenance.
(2) Dust generation system: accurate simulation of dust environment
This is one of the core components of the test chamber. It consists of a sand and dust storage unit, a sand and dust conveying unit, and a sand and dust dispersion unit. The storage unit can hold sand and dust of various sizes and compositions as required by the test. The conveying unit delivers the sand and dust into the test chamber using either a screw conveyor or an air conveying method. The dispersion unit ensures that the conveyed sand and dust is evenly distributed in the air, creating a stable and suitable sand and dust environment for testing, ensuring that each sample is thoroughly tested under uniform conditions.
(3) Air circulation system: create stable dust airflow
The air circulation system consists of a fan, ducts, and an air filter. The fan provides the necessary power to ensure the air circulates within the test chamber. The ducts guide the airflow effectively, ensuring that the air passes through the sand and dust generation system and the sample testing area, allowing the sand and dust to fully contact the samples. The air filter effectively removes sand and dust particles from the circulating air, protecting the fan and other equipment from damage and extending their lifespan.
(4) Control system: intelligent and accurate operation core
The control system employs an advanced programmable logic controller (PLC) and a touch screen interface. Operators can easily set and monitor test parameters, such as temperature, humidity, dust concentration, and wind speed, via the touch screen. It also features automatic adjustment capabilities, allowing it to continuously monitor and precisely adjust the various parameters inside the test chamber according to preset values, ensuring that the testing environment always meets the required standards. Additionally, the control system includes fault alarm and protection functions, which can promptly issue warning signals and take protective measures in case of any abnormal conditions, ensuring the safety of both equipment and personnel.
(5) Complete workflow: efficient and rigorous testing process
During the preparation phase, operators select appropriate sand and dust particles based on the test requirements and place them in the storage device. They then clean and inspect the test chamber and properly position the samples within the testing area. Once the test chamber is activated, the sand and dust generation system begins to operate, conveying and dispersing the sand and dust into the air. The air circulation system ensures a stable flow of sand and dust air. The control system continuously monitors and adjusts various parameters to maintain a stable test environment. During the sample testing phase, the test chamber operates according to the set schedule
When the Guangdong Hongzhan ice water impact test chamber is used in summer, the following matters should be paid special attention to to ensure the stable operation of the equipment and the accuracy of the test results:
1. Environment and heat dissipation management
Enhance ventilation and heat dissipation High temperature in summer is easy to lead to the decrease of equipment heat dissipation efficiency. Ensure that at least 10cm space is reserved around the equipment to promote air circulation. If the equipment adopts air cooling system, the condenser surface dust should be cleaned regularly to prevent poor heat dissipation and overheating of the compressor.Control the environmental temperature and humidity. Avoid placing the equipment in the direct sunlight area. It is recommended that the laboratory temperature be kept at 25±5℃ and the humidity be lower than 85%. High temperature and high humidity environment may accelerate the accumulation of frost or condensation water on the equipment, so it is necessary to increase the dehumidification measures.
2. Refrigeration system maintenance
Water quality and tank management Bacteria are easy to breed in summer, so use deionized water or pure water to avoid hard water scaling and blocking pipes. It is recommended to change the tank water every 3 days, and empty and clean the tank before long-term disuse.Refrigeration efficiency monitoring High temperature environment may lead to overload operation of the refrigeration system. The compressor oil condition should be checked regularly to ensure sufficient refrigerant. If the water temperature exceeds the set value (such as 0~4℃), the machine should be stopped immediately for troubleshooting.
3. Frosting and defrosting treatment
Prevent frost aggravation When the humidity is high in summer, the frost rate inside the equipment may accelerate. It is recommended to perform a manual defrosting process after 10 cycles: set the temperature to 30℃ and keep it for 30 minutes, and then drain water to clean the ice crystals on the evaporator surface.
Optimize the test interval to avoid continuous long-term low temperature testing. It is recommended to reserve 15 minutes of buffer time between high temperature (e.g., 160℃) and ice water shock cycle to reduce the impact of thermal stress on the equipment.
4. Adjustment of operation specifications
Parameter setting optimization According to the characteristics of the summer environment, the normal temperature recovery stage time can be shortened appropriately (the reference standard is to complete the temperature switch within 20 seconds), but it must ensure that it meets the requirements of GB/T 2423.1 or ISO16750-4 standards.Safety protection should be strengthened. Anti-freezing gloves and goggles should be worn during operation to avoid the adhesion of hands and low-temperature parts caused by sweating. Before opening the door after high temperature test, the temperature inside the box should be confirmed to be below 50℃ to prevent scalding from hot steam.
5. Emergency and long-term shutdown preparation
Fault response If the equipment has E01 (temperature out of tolerance) or E02 (water level abnormal) alarm, you should immediately cut off the power supply and contact the technical support of the manufacturer. Do not disassemble the refrigeration pipeline by yourself.Long-term protection When not used for more than 7 days, the water tank should be emptied, power should be cut off and dust cover should be covered. At the same time, power should be on for 1 hour every half a month to keep the circuit board dry.
Through the above measures, the impact of high temperature and humidity environment in summer on the ice water shock test chamber can be effectively reduced to ensure the reliability of test data and the service life of the equipment. The specific operation details should be adjusted according to the equipment manual and actual working conditions.
1. Dust adhering to the condenser can cause the high-pressure switch of the compressor to trip and issue false alarms. Therefore, dust attached to the cooling grid of the condenser can be removed with a vacuum cleaner every month, or by using a hard-bristled brush after turning on the machine, or by blowing it off with a high-pressure air nozzle.2. The area around the machine and the ground at the bottom should be kept clean at all times to prevent a large amount of dust from being sucked into the unit or reducing equipment performance and causing accidents.3. When opening or closing the door or taking samples from the test chamber, do not touch the sealing strip on the door.4. The core of the constant temperature and humidity test chamber - the refrigeration system should be inspected once a year. Check for leaks in the copper tubes and at each joint and interface. If there are any, inform the manufacturer.5. The humidifier and water tank should be cleaned frequently to avoid scaling and affecting steam emission. Clean them after each test. Timely descaling helps extend the lifespan of the humidification tube and ensures smooth water flow. When cleaning, use a copper brush and then rinse with water.6. The distribution room should be cleaned and inspected more than once a year. Loose nodes can put the entire equipment in a dangerous working state, burn out components, cause fires, alarms, and endanger lives.7. The dry and wet bulb wicks should be checked frequently. Replace them promptly if they become hard or dirty. It is recommended to replace them every three months.8. Inspection and maintenance of the water circuit. The water pipes in the water circuit are prone to clogging and leakage. Regularly check for leaks or blockages. If found, remove them promptly or notify the manufacturer.
When operating a constant temperature and humidity test chamber, it is important to be aware of potential issues during the process and ensure proper operation. Improper handling can easily lead to equipment malfunctions. However, over time, some faults will inevitably occur. In this article, we will discuss several common faults and their solutions.
Fault: If the temperature does not reach the set value during high-temperature testing, the first step is to check the electrical system and troubleshoot each component. If the temperature in the constant temperature and humidity test chamber rises too slowly, check the air circulation system to ensure the adjustment damper is functioning properly. If the temperature rises too quickly, adjust the PID settings. If the temperature rises too quickly and triggers the over-temperature protection, the controller may be faulty; in this case, replace the control panel or solid-state relay.
Fault: If the constant temperature and humidity test chamber fails to meet the low-temperature test requirements, investigate whether the temperature drops very slowly or if it stabilizes at a certain point before rising again. If the temperature drops very slowly, check if the chamber was dried before the low-temperature test to maintain dryness. Ensure the samples are not placed too densely to prevent inadequate air circulation. After ruling out these issues, consider whether the refrigeration system is malfunctioning; in such cases, seek professional repair from the manufacturer.
Fault: If the constant temperature and humidity test chamber malfunctions during operation, with the control panel displaying a fault message and an audio alarm, the operator can refer to the troubleshooting section of the equipment's user manual to identify the type of fault. Professional maintenance personnel should then perform the necessary repairs to ensure the test proceeds smoothly. Other environmental experimental equipment will have other conditions in use, which need to be dealt with according to the current situation.
Salah satu alasannya 1. Karena suhu ruang uji suhu dan kelembapan konstan tidak dapat dipertahankan, amati apakah kompresor pendingin dapat menyala saat ruang uji sedang berjalan, dan apakah kompresor dapat menyala saat peralatan uji lingkungan sedang berjalan, yang menunjukkan bahwa rangkaian dari catu daya utama ke setiap kompresor normal dan sistem kelistrikan tidak bermasalah.2. Tidak ada kesalahan pada sistem kelistrikan. Terus periksa sistem pendinginan. Pertama, periksa apakah tekanan buang dan hisap kompresor suhu rendah (R23) dari dua set unit pendinginan lebih rendah dari nilai normal, dan apakah tekanan hisap dalam keadaan vakum, yang menunjukkan bahwa dosis pendinginan unit pendinginan utama tidak mencukupi.3. Sentuh pipa knalpot dan pipa hisap kompresor R23 dengan tangan Anda, dan temukan bahwa suhu pipa knalpot tidak tinggi, dan suhu pipa hisap tidak rendah (tidak ada embun beku), yang juga menunjukkan bahwa refrigeran R23 di host tidak mencukupi.Alasan lainnya: 1. Penyebab kegagalan belum diketahui, dan konfirmasi lebih lanjut dilakukan dengan menggabungkan proses kontrol ruang uji suhu dan kelembapan konstan. Ruang uji memiliki dua set unit pendingin.Satu adalah unit utama, dan yang lainnya adalah unit tambahan. Ketika laju pendinginan tinggi, kedua unit beroperasi secara bersamaan di awal fase pemeliharaan suhu. Setelah suhu stabil, unit tambahan berhenti, dan unit utama mempertahankan suhu. Jika refrigeran R23 bocor dari unit utama, efisiensi pendinginannya akan berkurang secara signifikan. Selama proses pendinginan, kedua unit beroperasi secara bersamaan, memastikan suhu stabil dan penurunan bertahap dalam laju pendinginan. Dalam fase isolasi, jika unit tambahan berhenti, unit utama kehilangan fungsi pendinginannya, menyebabkan udara di dalam ruang uji naik perlahan. Ketika suhu mencapai level tertentu, sistem kontrol mengaktifkan unit tambahan untuk mendinginkan, setelah itu unit tambahan berhenti lagi. Penyebab kegagalan produksi telah diidentifikasi sebagai kebocoran refrigeran suhu rendah (R23) dari unit utama. Setelah memeriksa sistem pendinginan untuk kebocoran, retakan ditemukan pada batang katup solenoid bypass gas panas, berukuran panjang sekitar 1 cm. Setelah mengganti katup solenoida dan mengisi ulang sistem dengan refrigeran, sistem kembali beroperasi normal. Analisis ini menunjukkan bahwa diagnosis kesalahan mengikuti pendekatan langkah demi langkah, dimulai dari aspek 'eksternal' dan bergerak ke dalam, kemudian berfokus pada 'listrik' dan akhirnya pada 'pendinginan.' Pemahaman menyeluruh tentang prinsip dan proses pengoperasian ruang uji sangat penting untuk diagnosis kesalahan yang akurat.
1. Kondensor (atau radiator) unit pendingin di ruang uji kejut dingin dan panas harus dirawat secara teratur untuk memastikannya tetap bersih. Debu yang menempel pada kondensor dapat menyebabkan sakelar tekanan tinggi kompresor aktif, yang menyebabkan alarm palsu. Kondensor harus dibersihkan setiap bulan menggunakan penyedot debu untuk menghilangkan debu dari jaring pendingin kondensor, atau setelah menyalakan mesin, gunakan sikat berbulu keras untuk membersihkannya, atau tiup debu dengan nosel udara bertekanan tinggi.2. Saat membuka atau menutup pintu atau mengambil benda uji dari tungku, jangan biarkan benda tersebut menyentuh tepi karet pada pintu untuk mencegah tepi karet rusak dan memperpendek umur.3. Jaga tanah di sekitar dan di bawah badan pesawat tetap bersih setiap saat untuk menghindari kecelakaan dan penurunan kinerja yang disebabkan oleh banyaknya debu yang terhisap ke dalam unit.4. Sistem pembekuan ruang uji kejut dingin dan panas merupakan inti dari mesin ini. Harap periksa semua tabung tembaga untuk mengetahui adanya kebocoran dan kondisi salju setiap setengah tahun, serta semua nosel dan sambungan las. Jika terjadi kebocoran oli, harap beri tahu perusahaan atau tangani langsung.5. Kontak arus besar pada panel distribusi harus dibersihkan dan diperbaiki setidaknya setahun sekali di ruang distribusi. Kendurnya kontak akan membuat seluruh peralatan bekerja dalam kondisi yang berisiko. Paling banter, komponen akan terbakar, dan paling parah, dapat menyebabkan kebakaran, alarm, dan cedera diri. Saat membersihkan, gunakan penyedot debu untuk menghilangkan debu di ruangan.6. Jangan menyetel nilai pengaturan dua pelindung suhu berlebih di kotak distribusi daya ruang uji kejut dingin dan panas dengan sembarangan. Nilai ini telah disetel di pabrik. Sakelar pelindung ini digunakan untuk melindungi tabung pemanas dari pembakaran kosong dan alarm. Titik pengaturan = titik pengaturan suhu 20℃~30℃.7. Ruang Uji Kejutan Dingin dan Panas Saat mengambil produk uji pada saat tiba waktunya, produk harus dalam keadaan mati dan petugas harus memakai sarung tangan kering, anti listrik, dan tahan suhu saat mengambil dan menaruh produk.8. Bersihkan dan rawat bagian dalam dan luar ruang uji kejut dingin dan panas. 9. Sebelum mengoperasikan ruang uji kejut dingin dan panas, singkirkan semua kotoran internal. 10. Ruang distribusi listrik harus dibersihkan setidaknya setahun sekali. Saat membersihkan, gunakan penyedot debu untuk menghilangkan debu. Bagian luar ruang harus dibersihkan setidaknya setahun sekali, menggunakan air sabun untuk mengelapnya.
Perangkat ini berbeda dari peralatan biasa, sehingga lokasi pemasangannya harus memenuhi persyaratan khusus berikut:Lokasi harus memiliki ruang yang cukup untuk peralatan uji dan area perawatan yang memadai.Laboratorium harus dilengkapi dengan sistem pasokan air. Lokasi pemasangan harus memiliki fasilitas drainase yang ideal, seperti parit dan saluran pembuangan.Catu daya untuk perangkat harus memiliki sistem pentanahan yang baik dan alas serta penutup kedap air untuk mencegah kebocoran listrik atau sengatan listrik akibat cipratan air ke sumber listrik.Ketinggian lokasi pemasangan harus memungkinkan perangkat beroperasi secara normal dan memudahkan pemeliharaan serta perbaikan di masa mendatang setelah pemasangan.Suhu tahunan di lokasi pemasangan harus dijaga antara 5-32℃, dengan kelembaban relatif tidak melebihi 85%, dan harus ada ventilasi yang memadai.Pemasangan harus dilakukan di lingkungan bebas debu. Suhu lingkungan di lokasi pemasangan harus menghindari perubahan yang tiba-tiba.Pemasangan harus dilakukan pada permukaan yang rata (gunakan level untuk memastikannya rata).Pemasangan harus dilakukan di lokasi yang terhindar dari sinar matahari langsung. Pemasangan harus jauh dari bahan yang mudah terbakar, bahan yang mudah meledak, dan sumber panas bersuhu tinggi. Sebaiknya tidak memasang peralatan lain di laboratorium untuk mencegah korosi akibat kelembaban.Sumber air: air ledeng kota.