My home earth pit is very old and it's located at the front of the house. When checking the line and neutral I am getting average 250v. When checking the Line and the Earth, I am getting 238v.

Now, I want to install cloth dryer and washing machine at the rear of the house. My plan is to provide them a dedicated earthing.

Mt question is, can I connect the new earth with the existing earthing system? Will it improve the overall safety?

Please advise.

  • \$\begingroup\$ Where do you check the voltage between live and earth? What do you get when measuring between neutral and earth? If there is any current flowing in the wires then it will show up as voltage difference. Where is your earth bonded to neutral? You should not get these values as your measurements should not depend on your exiting grounding, unless there is a problem already or you have a weird grounding system (which we don't know what kind of system you have unless you tell us). \$\endgroup\$
    – Justme
    Jul 10 at 8:31

1 Answer 1


can I connect the new earth with the existing earthing system?

You can add additional grounding rods to an existing grounding system. Grounding rods on one side of the building can be bonded to grounding rods on the other side of the building using a ring ground or ground ring (same thing with different name), which is a bare copper wire strung along the foundation either slightly below the top of the soil, or sometimes a short distance above the top of the soil.

Although you can add additional grounding rods, what you should NOT do is connect any part of the grounding system to the neutral wire at any point other than in the principle breaker panel. Such a practice will generally degrade safety, and is a code violation in the US and may be in your jurisdiction as well.

Will it improve the overall safety?

If you live in an area with frequent lightning strikes, adding a ground ring around the building and multiple grounding rods may improve your grounding system's ability to absorb a nearby strike.

If your soil is very dry, or you live in a rocky area, and as a result your ground resistance is high, say over 25 \$\Omega\$, then such an addition may improve your lightning protection. However, the electrical code in your jurisdiction may already require that your grounding system's resistance to ground be below a given level, such as 25 \$\Omega\$. In such a case, multiple ground rods may already be present.

However, as far as protection from faults in your electrical system, adding a ground ring, or extra ground rods will likely not improve your safety. Ground Fault Current Interrupters (GFCIs) or their equivalent in your country, probably provide the best safety from shock and electrocution due to faults in your electrical system. The marginal improvement in safety from multiple ground rods, except in the cases mentioned above, will be minimal by comparison.

I am not a licensed electrician, and I am certainly not a licensed electrician in your jurisdiction. You should take the advice of such a licensed electrician, rather than from a stranger on the internet. However, my personal opinion is that 1) it won't hurt to add extra grounding rods, but 2) it is not worth adding extra ground rods except when either one rod provides insufficiently low resistance to earth, or if you live in an area where lightning strikes are frequent or a special concern. Again, this is the opinion of someone who is, to you, a random person on the internet. Treat my opinion as something you need to verify.

  • \$\begingroup\$ The mains socket earth and neutral should anyway be connected together somewhere in the house electrical system. Adding a new earthing rod and connecting it to existing rod would not change what voltages you measure inside the house at the socket, at least if the neutral and earth are bonded at the house. \$\endgroup\$
    – Justme
    Jul 10 at 8:35
  • \$\begingroup\$ @Justme Earth and neutral should be connected (bonded) ONLY at the primary electrical panel. At least that is what the US electrical code requires. It may be different in other countries, but as far as I know, connecting them elsewhere poses a safety hazard. \$\endgroup\$ Jul 10 at 12:56
  • \$\begingroup\$ Exactly, so how could adding an extra ground rod to same bonding point cause any changes in the measured readings between live/neutral and live/earth if technically nothing changed between live/neutral and live/earth, you just got better neutral to ground bonding, no changes in measured voltages. \$\endgroup\$
    – Justme
    Jul 10 at 13:00
  • \$\begingroup\$ @Justme The potential difference between the (grounded) metal frame of an appliance and the physical ground underneath where someone might be standing may vary depending upon the distance between the ground rod and the place where someone might be standing. Having a ground rod close to tåhe appliance will help ensure that such a potential difference is small. Having the nearest ground rod 100 feet away could permit the potentials to be significantly different. As far as safety goes, however, a fault between mains and the chassis of an appliance should be caught by a GFCI, regardless. \$\endgroup\$ Jul 10 at 13:18

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