1、Easy to use, convenient wiring, knob operation, the output signal immediately output after adjusting, no delay 2、The protection function is perfect: with the input voltage reverse connect protection , the power reverse connect, the instrument does not work, it will not be damaged by the reverse 3、The current regulation is very stable: the electric current is regulated by the wire-wound potentiometer 4、With dial, it can quickly locate and identify the running state of the equipment 5、Can be used in signal source generation, valve regulation, frequency converter control, PLC debugging, instrument test, led test, analog transmitter output Features: Easy to use, convenient wiring, knob operation, the output signal immediately output after adjusting, no delay. Voltage range: the input power is DC 5-28v DC,  suggested the power supply is 12-24v DC. The protection function is perfect: with the input voltage reverse connect protection , the power reverse connect, the instrument does not work, it will not be damaged by the reverse. Standard current output range: 4-20mA current output can be generated by manually adjusting the potentiometer on the product, which is used for the occasion of 4-20ma output of current simulation. The current regulation is very stable: the electric current is regulated by the wire-wound potentiometer, and the current is adjusted smoothly, which avoids the faults such as the resistance mutation which is often produced by the ordinary carbon film potentiometer. With the current meter, display precision With dial, it can quickly locate and identify the running state of the equipment. Fixed current output value: the output current can be automatically and constant at the setting point according to the customer's adjustment, and also can be used as a constant current source, and the current output should be no more than 20MA when used as a constant current source If the test output is normal, use a multimeter(DC current ) to connect the "current +" "current -"terminals to show whether the values are consistent with the multimeter reading. Can be used in signal source generation, valve regulation, frequency converter control, PLC debugging, instrument test, led test, analog transmitter output. Specifications: Current: 0-20mA Size: 8.5 x 7 x 4.2cm/ 3.34 x 2.75 x 1.65inch Weight: 185g The output impedance matching problem of the current generator: The output signal must meet the following requirements According to the formula: I=U/R (current = voltage divided by resistance) So your power voltage divided by your signal internal resistance is the maximum current that your signal receiver can generate. In addition, our current generator has some internal resistance. So here's the formula: Power supply voltage/(customer's signal resistance + internal resistance of our current generator) = constant current output Since the power supply of our module is 4-35v, the constant current generated by the module will not be sufficient if the power supply is low and the customer's internal resistance is larger. The signal matching requirements of our module are given below: Power supply is 24V,  the signal internal resistance ≤ 1000 Ω Power supply is 12V,  the signal internal resistance ≤ 500 Ω Power supply is 5V,  the signal internal resistance ≤ 200 Ω If the internal resistance of your signal is higher than the above parameters, it can be used to solve the problem of insufficient current supply of the constant current source by improving the power supply voltage or by reducing the internal resistance of the signal. Note that the supply voltage cannot be increased to more than 28V. Package Included: 1 x  4-20mA Current Signal Generator