The measurement of current in electrical appliance

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SUMMARY

The discussion emphasizes that measuring current in electrical appliances should not be done directly with a multimeter due to safety risks and the limitations of inexpensive multimeters, particularly their inability to measure AC current. Instead, users are advised to check the wattage rating on the appliance's label and calculate the current by dividing the wattage by the local mains voltage. Additionally, plug-in devices are recommended for safely measuring current and other electrical parameters, with an example device costing around $40.

PREREQUISITES
  • Understanding of electrical concepts such as voltage, current, and wattage
  • Familiarity with multimeters and their functions
  • Knowledge of AC current measurement limitations
  • Awareness of safety precautions when working with electrical appliances
NEXT STEPS
  • Research safe methods for measuring AC current in appliances
  • Learn how to calculate current using wattage and mains voltage
  • Explore various plug-in devices for monitoring electrical usage
  • Investigate the specifications and features of multimeters suitable for AC measurements
USEFUL FOR

This discussion is beneficial for electricians, DIY enthusiasts, and anyone involved in home appliance maintenance or energy monitoring, particularly those seeking safe methods to measure electrical current.

superkaho
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As we all know, the current should be measured in series with the multimeter...
However, how do we connect the multimeter in series with home appliance without damaging the wire(plug)??
 
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You don't do that at all with a multimeter. There are dangerous voltages inside appliances connected to the mains and you could easily kill yourself.
Apart from the danger, most cheap multimeters don't measure AC current.

If you want to know the current an appliance uses, read the wattage from the plate that is usually fixed to the side or bottom of appliances.

Then divide the power by the mains voltage in your area and that will give you the current.

You can buy plug-in devices which can be placed in a mains socket and have various appliances plugged into them. Then you can safely read the current, voltage, power, power factor, power usage, power cost and other functions depending on the unit.
I have one and I think it cost about $40
 

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