What's the theory behind this?

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EEC

Senior Member
Location
Maryland
When you take a hot conductor and make connect with neutral bar, there is a fault short-circuit. Why is it possible to connect a light bulb in between the hot conductor and neutral bar, there is no fault?
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
When you take a hot conductor and make connect with neutral bar, there is a fault short-circuit. Why is it possible to connect a light bulb in between the hot conductor and neutral bar, there is no fault?
Because the filament in the bulb has enough resistance (opposition to current flow) that there's not enough current flow to trip the breaker. The bulb behaves the same way whether it's at the panel or on the ceiling.

What you're describing is how a normal load behaves. The amount of current is enough to make the filament glow. Add enough bulbs in parallel (again, normal wiring), and the current will be enough to trip the breaker.
 
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gndrod

Senior Member
Location
Ca and Wa
Because the filament in the bulb has enough resistance (opposition to current flow) that there's not enough current flow to trip the breaker. The bulb behaves the same way whether it's at the panel or on the ceiling.

What you're describing is how a normal load behaves. The amount of current is enough to make the filament glow. Add enough bulbs in parallel (again, normal wiring), and the current will be enough to trip the breaker.

That's a lot of bulbs Larry.....:)
 

iwire

Moderator
Staff member
Location
Massachusetts
When you take a hot conductor and make connect with neutral bar, there is a fault short-circuit. Why is it possible to connect a light bulb in between the hot conductor and neutral bar, there is no fault?

The other guys are helping you with the electrical theory I will help with the terminology.


These are bulbs .....

Mixed_Bulbs_Sized.jpg


... gardeners plant them.

These are lamps .....


p-i-all.jpg
 

iwire

Moderator
Staff member
Location
Massachusetts
Well it must be true if Google says it.:roll: Hey you want to call them bulbs knock yourself out.:grin:

We can also call a panelboard a fuse box, the ungrounded a hot, a receptacle a plug and on and on.
 

Smart $

Esteemed Member
Location
Ohio
Well it must be true if Google says it.:roll: Hey you want to call them bulbs knock yourself out.:grin:

We can also call a panelboard a fuse box, the ungrounded a hot, a receptacle a plug and on and on.

In regards to an electric lamp, bulb refers to the shape.

Bulb lamp is appropriate.

Lamp bulb is not.


PS: "Light bulb" is appropriate in most parts of the country/world. :D
 
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