productbrief introduction

The turbine flow transmitter itself does not have on-site display function and only converts the flow signal into a two-wire system4～20mAThe current is transmitted in the form of remote output,External power supply+24VDCDistance of 500m for long-distance transmission.

The reason for using current signals is that they are less susceptible to interference. And the internal resistance of the current source is infinite, and the series connection of wire resistance in the circuit does not affect accuracy. It can transmit hundreds of meters on ordinary twisted pair cables. Upper limit selection20mABecause of the explosion-proof requirement: 20mAThe spark energy caused by the interruption of the current is insufficient to ignite the gas. The lower limit is not set to 0mAThe reason is to detect wire breakage: it will not be lower than 4mA during normal operationWhen the transmission line breaks due to a fault, the loop current drops to 0Usually take 2mAAs a disconnection alarm value.

Current output type transmitter converts physical quantities into4~20mAThe current output must be powered by an external power source. Typically, a transmitter requires two power lines and two current output lines, totaling 4 connectionsThe root wire is called a four wire transmitter.

Of course, the current output can share a common line with the power supply (common)VCCOr GND）It can save one wire and is called a three wire transmitter.

actually 4～20mAThe current itself can supply power to the transmitter. The transmitter is equivalent to a special load in the circuit, and its special feature is that the power consumption current of the transmitter is between 4-20mAIt varies depending on the sensor output. The display instrument only needs to be connected in series in the circuit. This type of transmitter only requires external connectiontwoThe root wire is therefore called a two-wire transmitter.

In industrial applications, measurement points are generally located on site, while display or control devices are typically located in control rooms or cabinets. The distance between the two may be tens to hundreds of meters. Calculated based on a distance of 100 meters, omittwoThe root signal transmission wire means a cost reduction of nearly a hundred yuan! In addition, four wire and three wire transmitters can use expensive shielded wires due to asymmetric current inside the wires,And two-wire transmitters can use very cheap twisted pair wires,Therefore, two-wire transmitters can solve related problems in applications.

External dimensions （Company:mm）