size conductors for 100 amp or less load

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Alwayslearningelec

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If your load is 100 A or less you must size to the 60° column unless the terminals are marked 75 which they usually are is that correct thank you
 
Correct. (It might be a bit better to say the "device" and not just the terminal)
 
infinity said:
True. I could have said it better but it was implied when I mentioned 2024 that I was referencing new installations.
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Recently installed a newly designed Milbank 400 amp (Class 320) residential combination service entrance device. Label states field installed conductors must be sized 60C for 110 amps or less. 75C for 125A and above.
 
curt swartz said:
Recently installed a newly designed Milbank 400 amp (Class 320) residential combination service entrance device. Label states field installed conductors must be sized 60C for 110 amps or less. 75C for 125A and above.
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That makes no sense. Do you have any photos of the label?
 
When I hear " terminal temperature ratings" a few questions:

1. What exactly are the "terminals" within a panelboard?
2. Do "terminals" refer to the load device or equipment as well? So, this could be receptacle terminals?
 
infinity said:
Thanks for the photo. This just proves that manufacturers are clueless. If the terminal/equipment is rated for 75° C it doesn't matter if it's less than 110 amps. :rolleyes:
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They must be considering the cross-sectional area of the conductor when evaluating the terminations ability to dissipate heat. I guess this would force you to use a larger conductor that could aid in wicking the heat away?
 
Alwayslearningelec said:
When I hear " terminal temperature ratings" a few questions:

1. What exactly are the "terminals" within a panelboard?
2. Do "terminals" refer to the load device or equipment as well? So, this could be receptacle terminals?
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The terminal is where you land a wire. It is not only the physical terminals that have a temperature rating, the equipment itself will also have a temperature rating. A lot of equipment manufacturers use 90° or even 105°C rated terminals, but they have an equipment temperature rating of 60° or 75°C. This happens because the equipment manufacturer buys generic termination devices to use in their product.
Yes receptacles have terminals and at temperature rating.

It is my opinion, that the 60°C ampacity limit in the picture that was posted only applies to conductors that are connected to a circuit breaker terminal.

Note that the 400 amp continuous meter panel shown in the picture is not compliant with the requirements in the 2020 or 2023 code as those codes prohibit to service disconnects from being in the same enclosure.
 
Tulsa Electrician said:
Any body catch the right side conductor limited to #6.
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The space between the right side breakers and the side wall is very small. 1-1/2" at most.

The label for this panel is actually incorrect. They used the same label they used on the old version of this panel. The new version has the second disconnect in a separate compartment between the meter and the section with the distribution. I don't know why they didn't make the panel wider to allow a full sized section for the distribution.
 
Tulsa Electrician said:
Any body catch the right side conductor limited to #6.
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That is probably a listing issue based on the amount of wire bending space between the terminal and he wall of the enclosure. Based on Table 312.6(A) that would suggest that there is less than 2" between the terminal and the side of the enclosure.
 
Thanks for the information. So it's an offset buss.

Nice looking install. Thanks for the description above. I was wondering if that center section feed the square d.
 
Tulsa Electrician said:
Thanks for the information. So it's an offset buss.

Nice looking install. Thanks for the description above. I was wondering if that center section feed the square d.
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Yes, the center 200 amp breaker feeds the SquareD loadcenter on the right.

The wireway extends past the loadcenters so the PV company has easy access to connect their inverter.

The backside of the wireway has the cables for 2 interior panels, 2 heat pumps and 2 EV chargers. Eventually there will be a 125 amp feeder to a Infratech heater control panel for (4) 6,000 heater at the covered patio.
 
don_resqcapt19 said:
The terminal is where you land a wire. It is not only the physical terminals that have a temperature rating, the equipment itself will also have a temperature rating. A lot of equipment manufacturers use 90° or even 105°C rated terminals, but they have an equipment temperature rating of 60° or 75°C. This happens because the equipment manufacturer buys generic termination devices to use in their product.
Yes receptacles have terminals and at temperature rating.

It is my opinion, that the 60°C ampacity limit in the picture that was posted only applies to conductors that are connected to a circuit breaker terminal.

Note that the 400 amp continuous meter panel shown in the picture is not compliant with the requirements in the 2020 or 2023 code as those codes prohibit to service disconnects from being in the same enclosure.
Click to expand...
I should have clarified sorry. I know exactly what terminals are. What I meant is what are terminals considered in a panel? The main lugs, the breakers????
 
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