Why choose 4-20mA transmission for electromagnetic flow meters?

1. The voltage signal is unstable and easily disturbed during long-distance transmission, while the current signal is relatively stable. During the transmission process, current signals are used, while voltage signals (the scale of voltage values) are used when mastering the instrument and DCS system in detail.

2. The signal with a range of 0-20mA cannot be distinguished from the fault signal. A signal of less than 4mA indicates a circuit malfunction, perhaps indicating a suspicion of zero drift. The birth of two wire instruments quickly led to a change in specifications, with a new standard for current signals of 4-20mA.

3. The 4-20mA specification is set for 2-wire sensors, where a current of 0-4mA is required to supply the sensor with a smaller working current. If 0-20mA is used, the sensor will not be able to obtain sufficient working energy when the signal is very small.

4. In fact, when it comes to 4-20MA signals, DCS systems typically set them above 20. 2mA is less than 3. 8mA is considered a fault.

Electromagnetic flow meters and other products not only need to be well-designed, time-saving and power-saving, but also need to achieve a stable effect in the application process. They not only consume time and effort in daily protection, but also can truly serve users and achieve good results