Finding Current Through Resistors

In order to impede electrical flow and making the flowing current safe for usage, you need to have electrical resistors, which are one of the components of an electronic circuit. By having this resistor, it will help you use your appliances without overloading them as well as injuring yourself. Whenever you detect that a resistor is faulty, you must make an effort to replace them before you start to use the device. The functionality of an electrical resistor can be tested by using a multimeter whereby the device would help you measure the voltage, resistance and also calculate the current.

What you need to do:

  1. Multimeter
  2. Pencil and paper



  1. In order to use your multimeter to check the current in your resistor, you must firstly turn on your multimeter on and plug the leads into the sockets.
  2. The red lead should be plugged into the socket that is marked ‘V omega’ while the black lead needs to be plugged into the socket that is marked ‘COM’. This method is used based on the studies done by the Southern Methodist University in Dallas.
  3. The next step is for you to set the meter in order to measure either alternating current (AC) voltage or direct current (DC) voltage. The setting that you need to do is based on the current that the resistor carries.
  4. To avoid damaging any components or blowing any fuse, you must turn the range of the meter higher than you expect to measure.
  5. After that, you have to turn the device’s power on and touch the multimeter probes leads to either side of your resistor before you start to record its voltage measurement. If the voltage reading is negative, it is time for you to replace the leads.
  6. Then, you should turn off the device’s power before changing the measurement on the multimeter to ohms. This goes the same for voltage measurement where you need to use a higher range that you expect to measure. Once done, you need to touch the leads to either side of the resistor and proceed with recording the resistance measurement.
  7. Apart from that, you can also calculate the electrical current through the resistor by using the Ohm’s Law. Based on the research done by Georgia State University, the Ohm’s Law holds the electrical current via a circuit that equals the ratio of voltage to resistance and therefore dividing your voltage measurement by your ohms measurement so that you would be able to calculate the electrical current in amperes.

Image Credit:

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Additional Reading:

MAKE: Electronics: Learning Through Discovery

Electronics For Dummies