Tap Taparoo

[ggonza]

I'm still a little confused about the tap rules. Are they there to permit no OCP when they fall within the specified code. For example, to allow you to come off a secondary of a transformer and land your wires on main lugs?

 

[ron]

The tap rules are able to permit you to go with a smaller conductor than the "run" and upstream protection, as long as you comply with the few limitations, whether it be tap size relative to run conductor size, length before landing in a OCPD, etc.

 

[augie47]

I'm still a little confused about the tap rules. Are they there to permit no OCP when they fall within the specified code. For example, to allow you to come off a secondary of a transformer and land your wires on main lugs?

There are a few sitautions that allow that. Look at 240.21(C)(1) and 240.21(C)(3)

 

[raider1]

Most of the time the tap rules permit a short length of smaller conductor to be "tapped" from a larger conductor and to locate the overcurrent protection device for the smaller conductors at the end of the tap conductors instead of at the start.

As Gus pointed out there are a few conditions where you are permitted to omit the overcurrent protection.

Chris

 

[TT009]

I will agree with the above...

I use the tap rule for transformers most often.

It would be nice to use it for multipule buildings (which you can run as long as you want "outdoors"), like agriculture building, which you would save the price of wire and run them all off the service.

 

[kbsparky]

....It would be nice to use it for multipule buildings (which you can run as long as you want "outdoors"), like agriculture building, which you would save the price of wire and run them all off the service.

In fact, you can. Read 240.21(B)(5) "unlimited length" I believe is the term used.

 

[ggonza]

Great thanks, it's starting to clear up a little.

 

[ibew501ed]

remember by terminating the wire in an OCPD that protects the smaller tap wires from overload and the rules of how to run the tap protects it from fault currents (hopefully).