3151/3051投入式液位變送器的傳感器局部可直接投入到液體中，變送器局部可用法蘭或支架固定，裝置運用極為便當，應用靜壓式采用洛斯蒙壓力傳感器原裝組件消費，主要用于城市給排水，水處置廠、水庫、河流、海洋、儲油罐、及石油、化工、電力等部門的液位丈量。
The sensor part of 3151 / 3051 input type liquid level transmitter can be directly put into the liquid. The transmitter can be fixed by flange or bracket, so the device is very convenient to use. The static pressure type adopts the original components of losmond pressure sensor. It is mainly used for the liquid level of urban water supply and drainage, water treatment plant, reservoir, river, ocean, oil tank, petroleum, chemical and electric power departments Measurement.
被測介質能夠是水、油、酸性、堿性及稀薄性液體。儀表輸出二線制4~20mADC規范電流信號，具有技術先進、精度高、質量穩定牢靠，裝置運用便當等優點，是一種過程檢測控制系統中理想的液位儀表。
The measured medium can be water, oil, acid, alkaline and thin liquid. The instrument outputs 4 ~ 20mADC standard current signal with advanced technology, high precision, stable and reliable quality, and easy to use. It is an ideal liquid level instrument in process detection and control system.
3151/3051投入式液位變送器采用靜液壓測量原理，當測量探頭放入液體中時，設大氣壓力為Po，液面到測量元件高為h，液體密度為r，當地重力加速度為g，則變送器探頭上所受壓力為：Pl＝Po+r×g×h，敏感元件的負側通過導氣電纜與大氣相通所受壓力為：P2=Po于是測量元件所測到的壓力差值為：P= Pl-P2=r×g×h，對于特定的液體介質和確定的地區，r和g均為常數，于是P口h，即可由儀表輸出電流大小得到液位高度，即水深。
The 3151 / 3051 input type liquid level transmitter adopts the principle of hydrostatic pressure measurement. When the measuring probe is put into the liquid, the atmospheric pressure is Po, the height from the liquid level to the measuring element is h, the liquid density is r, and the local gravity acceleration is g, then the pressure on the probe of the transmitter is: PL = Po + R × g × h, and the negative side of the sensitive element is connected with the atmosphere through the gas conducting cable, and the pressure is P2 = Po The measured pressure difference is: P = pl-p2 = R × g × h. for a specific liquid medium and a certain area, R and G are constants, so the liquid level height, i.e. water depth, can be obtained from the output current of the instrument at port P H.
3151/3051投入式液位變送器給水工控使用原理
Application principle of 3151 / 3051 input type liquid level transmitter for water supply industrial control
因為數據不準確的原因來自水流的沖擊，那么我們安裝投入式液位變送器時只要避免液體下流時壓力直接沖擊探頭，或者用其他的物體擋住液體下流時候那瞬間直接沖擊的壓力就可以了。
Because the data is not accurate because of the impact of water flow, so when we install the input type liquid level transmitter, we only need to avoid the direct impact of the pressure on the probe when the liquid flows down, or use other objects to block the pressure of the instant direct impact when the liquid flows down.
方法一、把進水口裝成淋浴式的，把一股大水流切斷成小水流噴灑下來，效果還不錯；
Method 1. Install the water inlet into a shower type, cut off a large stream of water and spray it down into a small one, and the effect is good;
方法二、把進水管口彎一下，使進水口略微往上翹一點，水在出來時會*先往空中拋然后再落下，減少了直接沖擊(將動能轉換成勢能)。
Method 2: bend the inlet pipe to make the water inlet slightly upward. When the water comes out, the water will be thrown into the air first and then fall down, thus reducing the direct impact (converting kinetic energy into potential energy).
方法三、在水中安裝內徑45mm左右鋼管，水流入口反方向位置打若干小孔，液位計探頭安裝在鋼管內可以減少沖擊，提高穩定性。
The third method is to install a steel pipe with an inner diameter of about 45mm in the water. A number of small holes are drilled in the opposite direction of the water inlet. The probe of the liquid level meter is installed in the steel pipe, which can reduce the impact and improve the stability.
3151/3051投入式液位變送器給水工控使用原理
Application principle of 3151 / 3051 input type liquid level transmitter for water supply industrial control
·注明測量范圍（液位高度），對于一些特殊介質，注明介質的密度。
·Indicate the measurement range (liquid level height), and for some special media, indicate the density of the medium.
·選型時，應注意被測介質與產品接觸的材料相兼容，對于特殊介質，可訂制。
·When selecting the type, it should be noted that the tested medium is compatible with the material contacted with the product. For special media, it can be customized.
·將投入式液位變送器安裝于多雷雨地區時，訂貨時應注明“防雷”，建議用戶在現場安裝防雷擊保護裝置，并確保產品及電源接地。
·When the input type liquid level transmitter is installed in Thunderstorm area, the "lightning protection" shall be indicated when ordering. It is suggested that the user should install lightning protection device on site and ensure that the product and power supply are grounded.
·關于導氣電纜長度的選?。阂话惚葘嶋H液位高度長10cm，不宜太長，如果現場到控制柜距離很遠，請選用優質導線電纜代替，不需要導氣電纜，導氣電纜做引線，使用中會出現問題，由于環境因素、工人因素如亂踩會使投入式液位變送器的導氣性能變差，亂壓造成氣不通，亂折容易把出氣口睹起來。建議用優質電纜代替，就不會出現以上故障了！
·The selection of gas conducting cable length: generally, it is 10cm longer than the actual liquid level height, and should not be too long. If the distance from the site to the control cabinet is far away, please use high-quality conductor cable instead. There is no need for gas conducting cable. As the lead wire, there will be problems in the use. Due to environmental factors and workers' factors, such as trampling, the air conduction performance of the input type liquid level transmitter will be deteriorated and the pressure will be disorderly It is easy to see the air outlet if the air is blocked. It is recommended to use high-quality cable instead of the above fault!
3151/3051投入式液位變送器給水工控使用原理
Application principle of 3151 / 3051 input type liquid level transmitter for water supply industrial control
二次儀表的硬件設計主要包括電源設計，A/D轉換設計，單片機外圍電路設計，顯示、報警、繼電控制設計，遠端通訊設計等。電源設計主要考慮變壓器應有足夠的耐壓和功率的降額設計，變壓器屏蔽層應接地。二次儀表中的模擬部分和數字部分及控制繼電器應由不同的變壓器副邊線圈供電，以防止大脈沖電流和電源波動的影響。整個電源在線路板的布局應遠離信號線路部分。
The hardware design of secondary instrument mainly includes power supply design, a / D conversion design, MCU peripheral circuit design, display, alarm, relay control design, remote communication design, etc. The power supply design mainly considers that the transformer should have enough withstand voltage and power derating design, and the shielding layer of the transformer should be grounded. The analog part and digital part of the secondary instrument and the control relay should be powered by different transformer secondary coils to prevent the influence of large pulse current and power supply fluctuation. The layout of the whole power supply in the circuit board should be far away from the signal circuit part.
A/D轉換芯片的選取應注重于產品的穩定性和可靠性，產品在出廠前應經過嚴格的老化和篩選。A/D的外圍電路的設計應特別注意參考電壓的穩定性。單片機外圍電路設計以基本程式化，但其通訊端口的軟硬件設計與A/D轉換芯片的數據交換方式有關，液位測量對測量頻率要求不高，單片機與A/D轉換芯片之間的數據交換可采用串口查詢方式，這樣程序結構清晰，便于編寫和調試。
The selection of a / D conversion chip should pay attention to the stability and reliability of the product, and the product should go through strict aging and screening before leaving the factory. Special attention should be paid to the stability of reference voltage in the design of peripheral circuit of a / d. The peripheral circuit design of single chip microcomputer is basically programmed, but the software and hardware design of its communication port is related to the data exchange mode of a / D conversion chip. The requirement of measurement frequency for liquid level measurement is not high. The data exchange between single chip microcomputer and a / D conversion chip can adopt serial port query mode. This program structure is clear and easy to write and debug.