1、Input pulse level is 5V 12V 24V, which can be directly entered without serial resistor. The input signal frequency must maintain more than 0.5 seconds. 2、The frequency of the pulse signal 0HZ to 10KHZ converts into an analog voltage signal of 0-10V. 3、Suitable for the switching of the PLC and the frequency converter. 4、This module is easy to wire and convenient to use. 5、Signal inputs with optical coupling isolation, which can ensure that the capability of anti-interfence. Description: Features: Input pulse level is 5V 12V 24V, which can be directly entered without serial resistor. The input signal frequency must maintain more than 0.5 seconds. Suitable for the switching of the PLC and the frequency converter. This module is easy to wire and convenient to use. Signal inputs with optical coupling isolation, which can ensure that the capability of anti-interfence. Specification: Output current: 5MA Input pulse level: 5V 12V 24V Frequency: 0 to 10KHZ Size: Approx. 4.5 x 4.5cm / 1.77 x 1.77inch Weight: 18g Quantity: 1pc Use: Signal inputs with optical coupling isolation. To ensure that the capability of anti-interfence. For use with PLC supported NPN type. Must have a ground wire. For with encoder requires constant speed of the encoder continuously rotate more than 0.5 seconds. If the signal input is turbine flow and so on, an 817 optical coupler and a resistor were needed to match the flow meter normally because of the signal match. Corresponding relationship: When the F / V with the resistance transferred to an intermediate value, F / v corresponding to the following relationship, 100HZ = 0.1V, accuracy is 1%. It can not reach to  2 digits after the decimal point if relatively high precision of the occasion is not enough. 0.1V = 100HZ 500HZ = 0.5V 1KHZ = 1V 2KHZ = 2V 3KHZ = 3V 4KHZ = 4V 5KHZ = 5V 6KHZ = 6V 7KHZ = 7V 8KHZ = 8V 9KHZ = 9V 10KHZ = 10V Each 0.1V DC of correspondence between the frequency 100HZ. When the correspondence if allowed, can be corrected to adjust to the board potentiometer. Package List: