Overhead neutral not insulated

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The electron man

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Hey guys I'm a NYC electrician that has only done underground P O E for the service ,

I notice the overhead service where a whether head is used the neutral in not insulated.

Why is it insulated underground but for the overhead its not ?
 
The electron man said:
Why is it insulated underground but for the overhead its not ?

Doesn't an uninsulated neutral pose a safety risk ??

Or since its already grounded there is really no risk ?
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A neutral service conductor may be bare all the way to the service disconnect.

We can touch it, or the bare SE cable wire, or the meter base, or the service enclosure, etc.

The neutral at the service "defines" the zero-volts reference of the premises.
 
LarryFine said:
A neutral service conductor may be bare all the way to the service disconnect.

We can touch it, or the bare SE cable wire, or the meter base, or the service enclosure, etc.

The neutral at the service "defines" the zero-volts reference of the premises.
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Won't the neutral be carrying the imbalance load ??
 
The electron man said:
Won't the neutral be carrying the imbalance load ??
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Yes, but there's a difference between current through a conductor and the voltage between it and earth.

The voltage from the neutral to earth becomes an issue when the neutral-current pathway is interrupted.

Remember that the EGC system is bonded to the neutral so a fault-to-ground mimics a fault-to-neutral.

Added: See this: https://forums.mikeholt.com/threads/understanding-the-neutral-conductor.140537/

See:

 
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LarryFine said:
Yes, but there's a difference between current through a conductor and the voltage between it and earth.

The voltage from the neutral to earth becomes an issue when the neutral-current pathway is interrupted.

See:

Click to expand...
You lost me. I have lots of learning to do on theory
 
Did not understand this

Yes, but there's a difference between current through a conductor and the voltage between it and earth.
 
The electron man said:
Hey guys I'm a NYC electrician that has only done underground P O E for the service ,

I notice the overhead service where a whether head is used the neutral in not insulated.

Why is it insulated underground but for the overhead its not ?
Click to expand...

The utility just wants to save money, that's what they do in Southern California.
 
The electron man said:
Did not understand this

Yes, but there's a difference between current through a conductor and the voltage between it and earth.
Click to expand...
The fact that current is flowing on the neutral does not mean its voltage will necessarily rise relative to earth.

Yes, in theory and practice it does, only slightly (unless compromised), due to current-caused voltage drop.

But that's why we re-establish it as a zero-volts-to-earth reference by tying it to local grounding electrodes.
 
infinity said:
If the neutral and the earth are at nearly the same potential then there is no voltage between them meaning that it is safe to have an uninsulated neutral even though it carries current
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Got its , but its only at the same potential till the service right ??
 
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