Make sure the socket base is made to use with 100-watt lightbulbs. If the power rating is too strong or weak, then the test may not work.
The light won’t turn on if the outlet you’re testing isn’t connected to power.
If the light is dimmer than your first test, then your outlet has earthing on it, but it may be faulty. Contact an electrician to inspect your electrical system to find the source of the problem.
You can buy multimeters online or from your local hardware store. Some multimeters may not have cutoff values listed on them. In that case, just switch the meter to the AC voltage setting and continue.
Avoid swapping the leads since you could cause the multimeter to short circuit.
Start by testing your multimeter on an outlet that you know works so you can see what a normal reading looks like. The ports where you attach the leads may differ depending on the type of plug you’re using. For example, on a type D or M plug, the live port is on the bottom right while the neutral port is on the bottom left.
If your home has earthing, then the reading should be the same as or within 5 volts of the first reading you took. If the reading between the live and earthing ports is close to 0, then you don’t have any earthing on that outlet. If your outlet doesn’t have an earthing port, then it isn’t connected and does not have earthing.
You don’t need to test the neutral and earthing ports if you’ve already determined you don’t have earthing on the outlet.
For example, if your first reading was 230 V, the second reading was 231 V, and the third was 0. 5 V, then your formula would be (231-230) + 0. 5, which simplifies to 1. 5 V. If you have faulty earthing, contact a licensed electrician to look at your electrical system to find the problem.
