How to choose a current transmitter is the key to accurately detecting and converting AC current. If the proper current transmitter cannot be reasonably selected, it will cause errors and distortions in the monitoring system in the future. First of all, we should choose the current transmitter to pay attention to the following problems: whether it is to detect single-phase current or three-phase current---current transducers usually have two forms, which can be used to detect single-phase or three-phase current. The range of the input current of the transmitter is large due to the range of actual load current. To adapt to this situation, we usually use a current transformer to convert the large current into a small current of 1A or 5A. Therefore, the input of the current transducer is usually selected according to the secondary current of the current transformer. For example, if the secondary current of the current transformer is 5A, the input current of the current transmitter can be selected to be 0-5A. The range of output DC signal is currently, the international standard for output signals, usually DC 4-20mA. As for why DC 4-20mA is used as the output signal, please refer to the special discussion of this blog. Of course, to output the DC signal, you can also use DC voltage (such as: DC 0-10V, etc.), and the input sleeve of the instrument or the automatic control device behind the current transmitter. Auxiliary Power Supply Specifications In order to accurately detect changes in input current and to output a DC signal that varies linearly with the input current, an auxiliary power supply is required to operate the most current transmitter. Usually, the most widely used is the AC 220V. You can also choose DC power, such as DC 24V and so on. It should be noted that there are some current transmitters that claim to require no auxiliary power, so-called "passive" current transmitters. For this type of current transmitter, it should be carefully selected. The so-called "passive type" does not require a power supply, but the working power supply is provided by the meter behind the current transmitter output signal. It is "eat the instrument power supply behind the transmitter". Naturally increases the burden of collecting the instrument behind the transmitter. There is also a "passive type current transmitter" that uses the secondary current of the current transformer as the power source for the transmitter. The disadvantage of this type of transmitter is that when the load current is small, the current output of the current transformer is naturally small, and the energy supplied to the transmitter is also reduced. At this time, the current transmitter will generate a nonlinear error, thereby According to the error of the current signal transmission, this kind of transmitter also needs to be used with caution. Current Transmitter Input Overload Capability When the load current is overloaded, or when the system fails, the current transmitter is typically subjected to very large overload currents. Under this circumstance, whether it can withstand large overload current becomes an important indicator to measure the performance of the current transmitter. For example: S3-AD series current transmitter, which can guarantee the transmitter will not be damaged for a long time when the input current is overloaded by 3 times. The SST3-AD series transmitters can withstand 5 times the overload current. The current transmitter's stability current transmitter is a kind of "metering type meter". In addition to the need for precision, the most important performance is whether it can work stably and reliably. These properties are often reflected in the design of the product. Due to changes in ambient temperature, any analog conversion type instrument cannot avoid temperature drift. In order to reduce the temperature drift of the product, various products adopt their own unique technologies from components and lines. And the product will be 100% aged before it is delivered to the customer. These contents are often not reflected in product sample indicators or marketing campaigns, and can only be selected by customers based on their own experience or experience. It is also reflected in the post-service provided by the product. For example, the SST3-AD series current transducers provide longer warranty than the S3-AD series current transducers. We believe that these contents are important indicators to measure the quality of product performance. This is a spy hidden camera with different lens angles, complete functions and a wide range of applications. Spy Hidden Camera,hidden video camera,spy camera,hidden spy camera,hidden cameras Jingjiang Gisen Technology Co.,Ltd , https://www.gisentech.com
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