HOW TO USE MULTIMETER

Measuring Continuity

• A continuity test tells us whether two things are electrically connected: if something is continuous, an electric current can flow freely from one end to the other.
• If there's no continuity, it means there is a break somewhere in the circuit. This could indicate anything from a blown fuse or bad solder joint to an incorrectly wired circuit.
• Continuity is one of the most useful tests for electronics repair.
• To begin, make sure no current is running through the circuit or component you want   to test. Switch it off, unplug it from the wall, and remove any batteries.
• Plug the black probe into the COM port on your multimeter.
• Plug the red probe into the VΩmA port  
• Switch on your multimeter, and set the dial to continuity mode (indicated by an icon that looks like a sound wave).
  Not all multimeter have a dedicated continuity mode.
  
  
  
   
• Ø  The multimeter tests continuity by sending a little current through one probe, and checking whether the other probe receives it.
  Ø  If the probes are connected—either by a continuous circuit, or by touching each other directly—the test current flows through. The screen displays a value of zero (or near zero), and the multimeter beeps. Continuity!
  Ø  If the test current isn't detected, it means there's no continuity. The screen will display 1 or OL (open loop).
  
  

  

  

  
  

  
  

  
  

  Ø  To complete your continuity test, place one probe at each end of the circuit or component you want to test.

  Ø  As before, if your circuit is continuous, the screen displays a value of zero (or near zero), and the multimeter beeps.

  Ø  If the screen displays 1 or OL (open loop), there's no continuity—that is, there's no path for electric current to flow from one probe to the other.

  Ø  Continuity is non-directional, meaning it doesn't matter which probe goes where. But there are exceptions—for instance, if there's a diode in your circuit. A diode is like a one-way valve for electricity, meaning it will show continuity in one direction, but not in the other.