Brushing up on 310.16

[eljefetaco]

If I ran a 100amp feeder and my terminals are marked for 75 degrees on both ends can I use the 75 degree column. You only use the 60degree if unmarked terminals 100 amp or less. Is this correct and is that what 110.14 (c)(1)(a)(1) means to you?

 

[augie47]

Actually you can use the 75? for any amperage as long as the equipment is identified for such.

 

[1793]

If I ran a 100amp feeder and my terminals are marked for 75 degrees on both ends can I use the 75 degree column. You only use the 60degree if unmarked terminals 100 amp or less. Is this correct and is that what 110.14 (c)(1)(a)(1) means to you?

Is this residential or commercial? What type of wire are you using?

 

[cadpoint]

If I ran a 100amp feeder and my terminals are marked for 75 degrees on both ends can I use the 75 degree column. You only use the 60degree if unmarked terminals 100 amp or less. Is this correct and is that what 110.14 (c)(1)(a)(1) means to you?

I thought the rating of the Panel would state it's limit via it's label, 100 amps where that cut-off from the NEC, what's that do to higher rated NEMA rated panels of 100 amps?

Doesn't the terminals at least match the buss of the panel inside as manufactured ?

here: "Unless the equipment is listed and marked otherwise, ... " from the opening lines of this article ...

Gezz, all these things to remember to attach a wire!

I understand the statement of an unmarked lug terminal.

 

[eljefetaco]

This is example is made up, I am studying and started thinking. Ouch! If you have a 100amp panel listed with 75degree lugs you use the 75 degree column. What if you have 125 amp panel, but no lug listing info available. Do you use 75 degree because it is above 100amp or must you use 6o degree because you cannot verify listing.

 

[electricmanscott]

This is example is made up, I am studying and started thinking. Ouch!

There are a bunch of variables that would need to be known to come up with a correct answer.

 

[RonPecinaJr]

This is example is made up, I am studying and started thinking. Ouch! If you have a 100amp panel listed with 75degree lugs you use the 75 degree column. What if you have 125 amp panel, but no lug listing info available. Do you use 75 degree because it is above 100amp or must you use 6o degree because you cannot verify listing.

I would say that depends on the OCPD protecting the feeders. If it's 100 amps or less use the 60? column, more than 100 amps use the 75? column.

 

[eljefetaco]

If you have a 60amp breaker rated 75 degrees and feeding 125 amp main lug panel rated 75 degree use 75 degree column? I do believe that is right if you have the known info.

 

[augie47]

as Norb pointed out you need to take into account what type wiring method you are using. Some are restrictive to the 60? ampacity.

 

[Dennis Alwon]

This is example is made up, I am studying and started thinking. Ouch! If you have a 100amp panel listed with 75degree lugs you use the 75 degree column. What if you have 125 amp panel, but no lug listing info available. Do you use 75 degree because it is above 100amp or must you use 6o degree because you cannot verify listing.

Yes, use the 75C column for a 125 amp panel that does not have the markings as long as your wire is rated 75C or greater. That is the simply answer that I believe you need.

 

[Vertex]

The wire must be rated for at least 75-degrees as well. 310.16, 240.4D

Temperature derating factors must be considered. This may include, number of current carrying conductors in raceway, ambient temperature, and roof locations. 310.15B2, 310.16

The equipment on both ends must have be listed for 75-degrees, not just the terminals on the equipment. 110.14C1

 

[cpal]

UL Listing AALZ Pg 47 08 White Book
Distribution and Control Equipment Terminations
Most terminals are suitable for use only with copper wire. Where aluminum
or copper-clad aluminum wire can or shall be used (some crimp terminals
may be Listed only for aluminum wire), there is marking to indicate
this. Such marking is required to be independent of any marking on
terminal connectors, such as on a wiring diagram or other visible location.
The marking may be in an abbreviated form, such as ??AL-CU.??
Except as noted in the following paragraphs or in the general Guide
Information for some product categories, the termination provisions are
based on the use of 60?C ampacities for wire size Nos. 14-1 AWG, and
75?C ampacities for wire size Nos. 1/0 AWG and larger, as specified in
Table 310.16 of the NEC.
Some distribution and control equipment is marked to indicate the
required temperature rating of each field-installed conductor. If the equipment,
normally intended for connection by wire sizes within the range
14-1 AWG, is marked ??75C?? or ??60/75C,?? it is intended that 75?C insulated
wire may be used at full 75?C ampacity. Where the connection is
made to a circuit breaker or switch within the equipment, such a circuit
breaker or switch must also be marked for the temperature rating of the
conductor.
A 75?C conductor temperature marking on a circuit breaker or switch
normally intended for wire sizes 14-1 AWG does not in itself indicate that
75?C insulated wire can be used unless 1) the circuit breaker or switch is
used by itself, such as in a separate enclosure, or 2) the equipment in
which the circuit breaker or switch is installed is also so marked.

 

[electricmanscott]

Yes, use the 75C column for a 125 amp panel that does not have the markings as long as your wire is rated 75C or greater. That is the simply answer that I believe you need.

I don't see how it is this simple.

 

[Dennis Alwon]

I don't see how it is this simple.

Well you can make it more complicated if you want. :grin: