Sensor accuracy configuration in high-precision constant temperature and humidity laboratory

Control accuracy up to: temperature precision ± 1.
0 °C, ambient humidity precision of ± within 2.
0% of the constant temperature and humidity air conditioning, called precision processing constant temperature and humidity air conditioning
.

Because most of this central air conditioner is used in the paper industry, textiles, pharmaceutical industry, cigarettes, electronic devices, measurement and verification and other industries that are more sensitive to temperature and humidity, it is also called laboratory special air conditioning
.

1, precision machining for constant temperature and humidity laboratory air conditioning and the general machine room air conditioning difference: A, precision machining for constant temperature and humidity laboratory air conditioning must have precision processing temperature and humidity sensor, the specified controller accuracy: ± 1.
5% RH, ± 0.
3 °C (at 23±2 °C) repeatability: better than 0.
5% RH and 0.
1 °C stability: over the years better than 1.
0% RH and 0.
1 °C and the general room air conditioning controller precision is ±3% RH, ± 1 °C is sufficient; B.
Precision processing for constant temperature and humidity laboratory air conditioning for the discharge air volume is higher in theory, the larger the exhaust air volume, the smaller the exhaust air enthalpy difference, the more uniform the temperature and humidity; However, the larger the exhaust air volume, the smaller the dehumidification work capacity, and even completely missing, so the precision processing constant temperature and humidity air conditioning regulations ensure that the dehumidification work capacity is basically as much as possible, and the design concept of the exhaust air volume is very strict, while the general machine room air conditioning regulations are low
.

C, precision machining for constant temperature and humidity laboratory air conditioning provisions for heat supply, air conditioning refrigeration capacity, humidifier capacity, dehumidification amount can be adjusted due to the precision of the regulations, precision processing for constant temperature and humidity laboratory air conditioning provisions for heat supply, air conditioning refrigeration capacity, humidifier volume, dehumidification amount can be adjusted
.

For heating, according to the size of the temperature difference, the multi-level heating method is selected to adjust, the temperature difference clock only opens the first level of heating, when the temperature difference is slightly larger, open 1, 2 levels of heating together, and when the temperature difference is large, open 1, 2, 3 levels of heating together; For the humidifier, the proportion display method is selected to manipulate the humidifier according to the size of the ambient humidity difference; For the adjustment of cooling and dehumidification, there are currently several adjustment methods: 1, 1 generation adjustment method, the selection of multi-level refrigeration, usually used for power machinery and equipment, suitable for the adjustment of temperature, the actual effect of environmental humidity adjustment is minimal; 2, 2 generation adjustment method, the selection of DC frequency conversion cooling, air conditioning cooling capacity from 50% - 100% in the middle to maintain no pole cooling adjustment, this adjustment category to deal with the problem
of temperature and humidity reliability.

It is used for precision machining as a constant temperature and humidity laboratory air conditioner, with remarkable
results.

Today's key brand is "Jotun"
.

However, because the handling is necessary, many auxiliary control stages need to be added, and the parts must be closely harmonized, and a slight slight common failure at a certain stage will cause the destruction
of key components such as refrigeration compressors due to chain reaction.

The repair rate in specific operation is very high; 3, 3 generations of adjustment methods, refrigerated water type refrigeration method, the selection of refrigerated water (according to the usual household central air conditioning temperature to carry out the design concept) as a non-cold source, the coil outside the operation is generally 7 °C up and down the cool water, the notebook motherboard according to the operation of the water inlet valve opening, casually maintain 0% to 100% air conditioning refrigeration capacity without pole adjustment
.

And the construction of the accumbratory valve is as simple as the domestic water faucet, the service life is very long, and there is no problem operating
for a long time.

Secondly, the enthalpy of water is 1,000 times that of gas and 800 times
that of snow species R22.

The use of refrigerated water for cooling, the temperature difference between the large inlet and outlet water is below 5 °C, which more reasonably ensures the uniformity and credibility of the exhaust temperature
.

The temperature difference between the snow before and before the end of the snow in the fan coil of the fan coil is more than 10 °C
.