Sensors and transmitters play a pivotal role in the fields of instrumentation, instrumentation and industrial automation. Unlike sensors, in addition to being able to convert non-electrical power into measurable electrical power, the transmitter generally has a certain amplification effect.
： How to choose a pressure transmitter :
Determine the measurement medium, look at the corrosion degree of the measurement medium, and select the corresponding transmitter according to the degree of corrosion. Generally speaking, non-strong acids and alkalis can use transmitters with stainless steel as the isolation unit. Corrosion designed titanium alloy and other special transmitters.
Secondly, you need to see if the measuring medium is thick and clean. If it is very thick (such as very slow flow), you need to choose a transmitter with a rigid isolation unit.
Determine the measurement range and measurement method
Generally, when selecting the measurement range, you should consider the actual measurement range and overvoltage measurement range. The selection range is based on the maximum measurement range, and the size of the overvoltage measurement range is also considered.
In addition, the correct measurement method needs to be selected. If measuring differential pressure, a differential pressure transmitter must be selected.
Determine accuracy range, compensation temperature range, use temperature range
According to the minimum accuracy you need to measure, generally choose a product slightly higher than the required minimum accuracy.
At the same time, long-term stability indicators need to be considered when selecting
The so-called compensation temperature range is the temperature range of the measuring medium during normal operation. The use temperature range is the maximum temperature range that may occur during use. Generally, it is slightly larger than the required temperature range when selected.
Determine pressure interface, electrical interface, mechanical dimensions, etc.
Determine if environmental protection is required for explosion protection, electromagnetic interference, and enclosure waterproofing
Difference between transmitter and sensor
With the advancement of technology, the meaning of some technical words has changed so much that it often causes misunderstanding. Sensors are one such example. Now people say that the sensor is composed of two parts, namely the sensing element and the conversion element.
Among them, the sensitive element refers to the part in the sensor that can directly sense or respond to the measurement; the conversion element refers to the part in the sensor that converts the measured or response of the sensitive element into an electrical signal suitable for transmission or measurement. Since the output signal of the sensor is generally weak,
It needs to be modulated and amplified. With the development of integrated technology, people also install this part of the circuit and power circuits inside the sensor together. In this way, the sensor can output a usable signal for easy processing and transmission. When the previous technology was relatively backward, the so-called
The sensor is the above-mentioned sensitive element, and the transmitter is the above-mentioned conversion element. ，流量变送器，电流变送器，电压变送器等等。 There are many types of transmitters. The transmitters used in industrial control instruments are mainly temperature transmitters, pressure transmitters , flow transmitters, current transmitters, voltage transmitters and so on.