Earth & Neutral Link

Please note that the neutral and the earth bars shall be linked or bonded ONLY (AND ONLY) at the Source Grounding Point and NOWHERE ELSE.

The neutral and the earth bars shall be linked (though only at the source) to ensure that the earth bar is kept at neutral potential always.

Yes! One can very well use a common Earth/Neutral Bar and it is called the TN-C System and then this bar is called the PEN Conductor. But, the problem is both the system unbalance current as well as the earth fault current would flow through the PEN (Protective Earth & Neutral) Conductor. One wouldn't be able to identify whether it is the unbalance current or the fault current. Thus, fault isolation becomes difficult thus endangering somebody's life.

I concur with electricalexpert, the earth and neutral should be linked at source. Normally speaking installers prefer to connect an earth wire from the MET (MAin earth terminal) to the shield of the main cable, this will eventually be earthed at the earth substation side from the neutral star point. Here now your relying that the electrical supplier's earth is good enough. However some countries do not guarantee that it should be the case and this would be at your own risk. Generally speaking it is advisable to design a TNS system having your own earth through earth electrodes or earth mats.

Some will not always guarantee 0Amps in the neutral feeder. (not the ideal world)

Dear all,

In case TN-CS:

Neutral-Earth link is to make neutral and earth equal potential.

In case TN-S:

Neutral-Earth link is to make earth-fault return current pass. Without return current pass, an earth-fault will not be cleared by an MCB or MCCB.

If we have separate Neutral and Earth bars, you can connect neutral wires to neutral bar, PE wires to Earth bar (installation easy). If you need to check the insulation, remove the neutral-earth link, and put your megger probe on the neutral bar (maintenance easy). You can have a common neutral and earth bar at the distribution panel the first one from your power source, if you do not care about installation and maintenance. There will be no Neutral-earth link other than the first one.

Regards