The high and low temperature alternating humidity test chamber is used to test and determine the parameters and performance of electrical, electronic, and other products and materials after temperature, humidity, or constant temperature environmental changes during temperature, humidity, or constant testing.
Maintenance details of high and low temperature wet heat test chamber:
1、 Environmental and installation requirements
-Venue selection: It should be placed in a well ventilated, independent space without direct sunlight, away from heat sources and corrosive gases. The ground should be flat and have a load-bearing capacity of ≥ 300kg/m ², with at least 50cm of operating distance reserved around it.
-Power configuration: Adopting a three-phase five wire system for power supply, with a voltage fluctuation range of ≤± 10% and a grounding resistance of<4 Ω. It is recommended to equip a regulated power supply or UPS to prevent sudden power outages from damaging the control system.
-Water quality management: If equipped with a water circulation system, deionized water or distilled water must be used to avoid scale clogging the pipeline. Check the hardness of water quality every month, and replace the water source if it exceeds 50ppm.
2、 Special scenario response strategies
-Extreme cold mode operation: When the set temperature is below -40 ℃, the pre cooling device needs to be turned on in advance to gradually reduce the frequency of the compressor and avoid liquid impact damage to the vortex disc.
-High temperature and high humidity coupling: Under the working conditions of 85 ℃/85% RH, perform a door seal condensation check once per hour. If any accumulated water is found, immediately wipe it off and apply silicone grease for lubrication.
-Rapid temperature change test: When the linear heating rate is greater than 5 ℃/min, it is forbidden to load brittle samples such as glassware to prevent thermal stress rupture.
3、 Application of intelligent monitoring system
-Remote warning function: After connecting to the IoT platform, the following parameters can be viewed in real-time through a mobile app:
-Abnormal fluctuation of compressor current (threshold ± 15%)
-The water level in the humidification tank suddenly drops (below the low mark)
-Attenuation of blower motor speed (decrease>10% from nominal value)
-Self diagnostic log: The device automatically generates a fault code table, for example:
-E01: Humidity sensor open circuit
-E07: Refrigeration high pressure protection triggered
-E12: Insulation failure of heating tube
4、 Safety operating procedures
-Prohibited items list: It is strictly prohibited to include explosives (nitrocellulose), self igniting substances (yellow phosphorus), highly corrosive substances (concentrated sulfuric acid), and biological samples.
-Emergency handling process:
-Overtemperature alarm: Immediately cut off the main power supply and keep the cooling fan running until the box cools down to a safe range.
-Leakage accident: Close the inlet valve → Drain the humidification water tank → Contact after-sales maintenance.
-Smoke detection: Activate the emergency exhaust system and use a carbon dioxide fire extinguisher to extinguish the fire.
5、 Energy saving optimization plan
-Load matching principle: The total volume of the sample should not exceed one-third of the working chamber volume to ensure smooth airflow circulation.
-Program segment setting technique: Combine tests with the same temperature and humidity conditions to reduce energy loss caused by frequent start stop.
-Night mode adjustment: During non working hours, the set value can be switched to room temperature and humidity to reduce standby power consumption.
6、 Annual deep maintenance project
-Refrigeration system leak detection: An electronic leak detector is used to perform helium mass spectrometry leak detection on solder joints/valves, with a leak rate of<1 × 10 ⁻⁶ Pa · m ³/s.
-Electrical cabinet dust removal: Use an industrial vacuum cleaner with an anti-static brush to clean the dust accumulation on the frequency converter/PLC module.
-Damp heat aging test: Simulate continuous operation at full load for 90 days to verify the reliability of the entire machine.