Temperature sensor selection method
Source：Sentech Hits： Date：2018.03.28
Currently, the baffle can be designed according to the size of the water flow to reduce the water resistance generated by the flow of water through the flow sensor and reduce the head loss of the water system. However, due to the long-term impact of the flow of the baffle, there is still a problem of fatigue, even if the flow rate is calibrated at the factory. Setpoint drift also occurs for values.
It is usually used where the protection flow value is not required to be precise, ie, the cut-off protection for sudden interruption of the water flow in the water pipe. There are very few designs for water source heat pump units in China.
The baffle type is specially developed for water flow monitoring of water ring/ground source heat pump air conditioning units. It is equipped with different baffles for different pipe diameters, and the water resistance of each baffle is not more than 0.5 m water column. Target water resistance has been greatly reduced.
Each baffle type flow sensor is equipped with the same pipe fitting as the water ring heat pump unit water pipe, and the site only needs to connect the water pipe, without any change to the baffle, and the pressure of the baffle type water flow switch is greater than 25 bar. The water ring heat pump unit, which does not require high water flow, is a low-cost water flow switch.
According to the feedback used on the water ring/ground source heat pump unit, the pressure difference switch can effectively determine the problem of the water pipeline installed on the water ring heat pump unit at the site, which can completely avoid the situation in which the heat exchanger is frozen and the flow rate is small due to the small water flow. The sensor can also protect the heat exchanger from freezing when the flow rate of water is reduced due to the blockage of the water filter. In addition, the water line pressure difference switch does not have the risk of fatigue failure of the target switch.
In particular, when there is a small amount of air in the water pipeline, the flow sensor operates very stably, and there will be no floating situation similar to the target flow switch. After years of feedback, the differential pressure switch itself has not been found to be faulty.