Dongguan Haotian Testing Equipment Co., Ltd
yuhongmei0812@163.com
13712072775
Building 2, Yihai Science and Technology Park, No. 25 Yuanxia Road, Changping Town, Dongguan City, Guangdong Province
Below are several key dimensions for detailed comparison:
| feature dimension | Conventional constant temperature and humidity test chamber | High and low temperature alternating humidity test chamber |
|---|---|---|
| core functionality | keep oneSet unchangedTemperature and humidity points. | Under the set program control, adjust the temperature and humidityChange over time according to the preset curve. |
| control logic | Fixed value controlAfter reaching the set point, maintain stability. | program controlMultiple programs can be written, each with different temperature, humidity, and duration settings. |
| Test purpose | Assessing products inUnder a constant climate conditionWeather resistance, performance stability, storage adaptability, etc. | Assessing products inUnder the stress of temperature and humidity cycling changes (especially high and low temperature conversion)Reliability, stability, and potential defects. |
| simulated scenario | Products that have been in a stable environment for a long time, such as warehouse storage or use in a fixed area. | Temperature difference between day and night, seasonal changes, geographical migration, thermal shock during power on/off, condensation, etcdynamic environment. |
| system complexity | Relatively simple. Having heating, cooling, humidification, and dehumidification systems is sufficient. | extremely complexIn addition to the basic system, requirements for controller algorithms, sensor response speed, refrigeration unit power, duct design, etchighTo achieve rapid and precise temperature and humidity changes. |
| cost | Lower. | far aboveConventional boxes, due to their complex technology and high requirements for components. |
working methodSet a target temperature (such as 85 ℃) and humidity (such as 85% RH), operate the equipment and stabilize at these conditions until the end of the experiment.
Key abilities：Control accuracy and uniformityIt is its core indicator. Within an effective workspace, the smaller the fluctuations and deviations in temperature and humidity, the better.
Typical Applications：
Moisture absorption test of materials.
Life testing of electronic components in specific environments.
Stability storage tests for drugs and food.
Aging test of textiles and plastics under constant humidity and heat.
working methodCan write complex programs. For example:
Program segment 1: Heat up from 25 ℃ to 60 ℃ within 30 minutes, maintain a humidity of 95% RH, and hold for 2 hours.
Program segment 2: Cool down from 60 ℃ to -10 ℃ within 15 minutes, while dehumidifying (humidity cannot be controlled), and maintain for 1 hour.
Program segment 3: Within 40 minutes, rise from -10 ℃ to 25 ℃, increase the humidity to 75% RH, and maintain it .....
Key abilities：heating and cooling rate、The flexibility of program arrangement、The ability to control humidity during the high and low temperature conversion process(This is a technical difficulty) is the core indicator.
Typical Applications：
Automotive ElectronicsSimulate the environment of a car being exposed to sunlight from cold nights to daytime, as well as internal condensation.
aerospaceSimulate the drastic temperature and humidity changes of equipment during rapid ascent and descent.
communication equipmentTest the reliability of the equipment under outdoor four season alternation and day night cycle.
PCB board and componentsPerform Accelerated Stress Testing (ESS) to quickly expose welding and material defects.
National defense and scientific researchConduct more rigorous environmental adaptability verification.
When choosing, please make sure to refer to yourProduct testing standardsStandards such as GB/T, IEC, MIL, ISO, etc. will clearly specify whether to use "constant test" or "alternating cycle test".
Choose a regular constant temperature and humidity chamber, if：
Your testing standard requires a 'constant humidity test'.
You only care about the performance of the product in a specific but stable environment.
Your budget is limited and there is no need for dynamic change testing.
It is necessary to choose a high and low temperature alternating humidity box. If：
Your testing standards require conducting "temperature cycling", "wet heat alternating", or "temperature humidity combined cycling" tests.
You need to evaluate the fatigue and failure of the product under alternating stresses such as thermal expansion and contraction, condensation and evaporation.
You want to conduct more realistic and rigorous environmental simulations to discover potential defects.