Question 1: users who use the constant temperature and humidity test chamber for the first time may encounter this situation. The humidity suddenly shows 100% in the test process, but they do not know what causes it.
Step 1: Check whether the wet bulb gauze is hanging on the humidity sensor.The sensor near the sink is the humidity sensor. The gauze should be hung on the humidity sensor and cover the temperature sensing part of the sensor.There are a few customers often hang gauze in the wrong position, hanging on the temperature sensor, causing machine failure, therefore, please carefully identify, the top for the temperature probe, the following near the sink for the humidity probe.
Step 2: if the humidity still shows 100% without error in the hanging mode, please check whether the wet bulb gauze is yellowing, or if the gauze is used for too long, too many minerals are accumulated on the gauze, resulting in the water absorption performance of the wet bulb gauze decreased, and the water absorption is not able to be absorbed, thus making the detected humidity inaccurate and causing the false image of high humidity;If so, please replace the wet bulb gauze. If not, check that there is no water in the wet bulb sink or the water level is low and the gauze can not absorb water. Focus on the following parts:
A. Obtain whether there is water in the water level box near the sink. If there is no water, it may be damaged by the float ball.
B. The electromagnetic pump is damaged. Use the voltage range of the multimeter to measure its resistance. If the pump is open, it will be damaged.
C. The gap water filling timer is damaged and cannot be replenished normally.
Step 3: There is also a controller setting problem. A few customers have a mistake in the use of the constant temperature and humidity test chamber. They often set the humidity at low temperature, and set the humidity at high temperature of 120 degrees Celsius.Low temperature machine can not control the humidity, easy to freeze;High temperature evaporation is too fast, the machine is also very difficult to set the humidity.Therefore, please read the instructions carefully, standardize the operation of the machine, prolong the service life of the equipment.
Question 2, constant temperature and humidity test box out of use for a long time what to do?
If due to special circumstances, the constant temperature and humidity test chamber needs to stop using for a period of time, then some protective measures should be taken, the specific methods are as follows:
(1) When the constant temperature and humidity test box is out of use, the items in the box should be taken out, the power plug should be pulled out, and the inside and outside of the test box should be cleaned.
(2) between the door seal and the box body is padded with paper to prevent adhesion between the door seal and the box body;If you are not prepared for a long time, you can also apply some talcum powder on the door seal.
(3) The constant temperature and humidity test chamber after disuse must also be placed in a dry and ventilated place, avoid direct sunlight, and the test chamber should be placed smoothly after the position is moved.
(4), indoor air has a certain humidity, so do not use plastic bags to cover the test box, moisture is not easy to distribute, resulting in metal parts rust and damage to the performance of the electrical original.
(5), constant temperature and humidity test chamber refrigeration Freon solidification temperature is very low, so there is no need to worry about it will freeze and put the test chamber in a high temperature place.
(6), the condition is best to connect the power supply once a month, then the compressor normal operation for half an hour to an hour later shut down.
Question 3. The correct placement of wet bulb gauze in the constant temperature and humidity test chamber
When conducting humidity and heat test, wet bulb gauze plays an important role in humidity perception of constant temperature and humidity test chamber.Therefore, the correct placement and maintenance of wet bulb gauze must follow certain norms and steps:
1. Take the wet bulb gauze out of the packaging box and cut about 10cm;
2. Put the lower end of the wet bulb gauze into the sink to wet it (it is easier to perceive the humidity), and hang it or set it on the humidity sensor.
Maintenance and inspection of wet bulb gauze in the constant temperature and humidity test chamber: the upper end of the wet bulb gauze must be hung on the wet bulb sensor, and the lower end should be put into the wet bulb gauze tank, so that it can easily absorb the water in the tank and be soaked.If the wet bulb gauze is installed in other places, the humidity sensor will not be able to perceive the humidity, leading to the illusion of 100% humidity, humidity cannot fall or humidity can not be controlled at all.When doing humidity test, it is necessary to check whether the wet bulb gauze is hung well. If it is hung well, please check whether the gauze is wet. If it is baked dry or the water absorption effect is poor, please replace the wet bulb gauze in time.
Question 4. How to maintain and clean the constant temperature and humidity box in daily work?
1. Cleaning and maintenance inside and outside of the constant temperature and humidity box.
The constant temperature and humidity test chamber should be cleaned up before operation.
② The power distribution room should be cleaned at least once a year, and the indoor dust can be sucked out by a vacuum cleaner when cleaning.
(3) the outside of the box body must be cleaned more than once a year. When cleaning, wipe it with soapy water first.
2, constant temperature and humidity box humidifier inspection and maintenance.The water stored in the humidifier should be replaced once a month to ensure clean water quality, and the humidifying water tray should be cleaned once a month to ensure smooth water flow.
3, constant temperature and humidity box condenser dust cleaning.The cleaning condenser should be maintained regularly every month, and the dust attached to the condenser’s heat dispersing net should be sucked up by a vacuum cleaner or the dust should be sprayed by high-pressure air.
4. Replacement of wet bulb test cloth in constant temperature and humidity box When the surface of the test cloth is not clean or hardened, or after the temperature control, the test cloth must be replaced before continuing to do temperature and humidity bulb control.The test cloth should be replaced once every three months. A clean cloth should be used to wipe the temperature measuring body. Clean the test cloth before replacing it.
5. Check the water level of the wet bulb of the constant temperature and humidity box and adjust the water level of the water accumulator. Do not overrun the water level of the water accumulator or too low, so that the water absorption of the wet bulb test cloth is not normal and the accuracy of the wet bulb can be affected by keeping the water level about six minutes full.To adjust the water level of the water collecting tank, the height of the water collecting box can be adjusted.