Three phase tester


Posted on Apr 10, 2012

This simple three-phase tester, uses only a small current thyristor as a main element for testing the right or wrong succession of the three phases, and there is no need for a supplementary power supply. The basic circuit is shown in Fig. 69-4A. When connecting to the thyristor anode, grid, and cathode the three phases of the supply network in the sequence phase 1, phase 3, phase 2, are considered as correct, the mean value of the current through the thyristor is relatively high (since it is turned on during an entire half-period of one phase). The result is that the LED will emit a normal light. The wave shapes for the three voltages and the current through the LED for this situation are shown in Fig. 69-4B.


Three phase tester
Click here to download the full size of the above Circuit.

If the three phases are not correctly connected—phase 1 to the anode, phase 2 to the grid, and phase 3 to the cathode, for instance—the thyristor will be turned on for a very short time and the LED wili produce a very poor light. The wave shapes for this case are shown in Fig. 69-4C. The delay time is given by the R3-R1-R4 group. When any of the three phases is missing, there is no current through the thyristor and the LED will emit no light.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Room Noise Detector
    HiFi stereo preamplifier with tone control
    12-Vdc-battery-operated-120-vac-power-source
    One-mospower-fet-analog-switch
    diy-solid-state-relay.html
    The E-meter
    300m FM transmitter circuit design project
    Modular Signal System Implementation
    One infrared burglar alarm circuit
    Analog counter circuit diagram
    Stepping BA2101 touch dimmer light circuit
    Photoelectric counting circuit diagram



    Top