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Wilson12

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i couldn't find the answer to,
Why is the neutral bar not live in simple terms.
Im thinking
Line from mcb to equipment then neutral connected from the load to the neural bar to complete the circuit with 230 v throughout the circuit?
I'm wrong I know but why?
 
if the N bar is not connected to the supply N, then you're right. with no current flow, there is no volt drop, so you will have 230V on the N bar. however, once the N bar is connected to the supply N, the 230V will be dropped across the load as in ohm's law V = IR, so 0V on the N bar. hope that seems clear.
 
As per tel
Voltage drop across the load

The potential difference between live and neutral is bridged by a load with an impedance
The value of that impedance is what allows a level of current to flow when the load bridges the live-neutral supply

If live is shorted to neutral the current flow will be of such magnitude that either whats protecting the circuit will pop or the supply transformer will burn out
 
And in UK the neutral bar will likely be connected to the "general mass of the earth" by the supplier's neutral.
 
i couldn't find the answer to,
Why is the neutral bar not live in simple terms.
Im thinking
Line from mcb to equipment then neutral connected from the load to the neural bar to complete the circuit with 230 v throughout the circuit?
I'm wrong I know but why?
230 V wrt what? That's what you need to think about.
It's a potential difference.
 
To expand, 'wrt' is shorthand for 'with respect to', meaning the voltage at a point is measured relative to some other reference point. Earth / ground is a conductor that more or less everyone has access to, and is often in contact with, so it makes a very sensible reference point for defining the voltages in an electrical supply system. When we say casually that a conductor 'is live' we generally mean with respect to earth. As mentioned above, in most supply systems the neutral is solidly connected to earth at source, so it generally cannot become 'live' with respect to earth under normal conditions.
 
Just to add a note,in respect of neutral being classed as live,in terminology,is it's possibility to become a danger,when disconnected from it's connection to earth at source.

A very common scenario,is for the uninitiated,to test a conductor at, say a light fitting,with a probe or neon,get no indication,disconnect the conductor,and receive a surprise.

In this respect,the neutral will become "live",carrying line voltage,through a connected load,and to earth,through the individual.

These are valuable examples to remember,when disconnecting items such as earth ,bonding and cpc's,on systems where they may be existing faults,which have not given any problems or indication,but can manifest a risk,on removing.

The above is obviated,by using the correct testing methods.
 

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