Flir question.. Max breaker temp? operating range ?

[rt66electric]

I have recently obtain a FLIRone for Christmass,

really cool, but he resolution could be better.

What is the critical temperature for the average cutler hammer BR20 single pole breaker?? and similar brand breakers (GE, Squre-D etc....)breakers 240 volt 20-100 amp 1P or 2P.

I have the used the "three second thumb rule" in the past ( if you cant hold you thumb on it for more than three seconds--its overloaded) .

Most every panel will shown a warm breaker or two, and a person can judge the ampload on a wire by looking at the delta-T.

what is the maximum operating temp of an average breaker?
What is a concerning Delta-T for residential grade breaker/bus ??
Should the point of measurement be -face the breaker(panel cover on), or, at the terminal screw, or, at the bus stabs??

Thank you Dennis

 

[Tony S]

Everything you’ve asked is in the manufacturer’s literature.

As for “if you cant hold you thumb on it for more than three seconds - - its overloaded”

Four seconds it will be on fire ! ! ! !

 

[romex jockey]

The Q's you ask are multi level Dennis

We would normally utilize 110.14 as a benchmark .

hanging one's hat on the specifics of ocpd's thermal qualities would be nefarious at best, as they are tested solo vs. side by side with other loaded ocpd's.

Any final temp calc would need a consistent load applied , as well as within the environ it would normally be operational doing so

Others may opine in detail....

~RJ~

 

[mgookin]

I have recently obtain a FLIRone for Christmass,

really cool, but he resolution could be better.

What is the critical temperature for the average cutler hammer BR20 single pole breaker?? and similar brand breakers (GE, Squre-D etc....)breakers 240 volt 20-100 amp 1P or 2P.

I have the used the "three second thumb rule" in the past ( if you cant hold you thumb on it for more than three seconds--its overloaded) .

Most every panel will shown a warm breaker or two, and a person can judge the ampload on a wire by looking at the delta-T.

what is the maximum operating temp of an average breaker?
What is a concerning Delta-T for residential grade breaker/bus ??
Should the point of measurement be -face the breaker(panel cover on), or, at the terminal screw, or, at the bus stabs??

Thank you Dennis

On a CH BR spec sheet they list ambient at -31 to 66C (32 to 151F)
http://www.google.com/url?sa=t&rct=...n90w_qUoraG1yQjaVNW19A&bvm=bv.110151844,d.eWE

But that can't be right because -31C is not 32F.

You can call them United States
877-ETN-CARE (877-386-2273)

Ambient and operating are two different things. As others have said there's the load to consider, proximity to other heat sources, airflow, etc.

There has to be a "critical number" which they should be able to provide.

 

[user 100]

I have recently obtain a FLIRone for Christmass,

really cool, but he resolution could be better.

What is the critical temperature for the average cutler hammer BR20 single pole breaker?? and similar brand breakers (GE, Squre-D etc....)breakers 240 volt 20-100 amp 1P or 2P.

I have the used the "three second thumb rule" in the past ( if you cant hold you thumb on it for more than three seconds--its overloaded) .

Most every panel will shown a warm breaker or two, and a person can judge the ampload on a wire by looking at the delta-T.

what is the maximum operating temp of an average breaker?


Thank you Dennis

I think that if your looking for a general benchmark for max temps for cbs UL 489 should suffice and same concerns with panel buswork would probably be UL 67(?)

Sorry I don't have any links.

 

[kwired]

But that can't be right because -31C is not 32F.

.

Possible typing error?

-31C is -23.8F, maybe interposed 23 and completely missed the negative sign?

 

[mgookin]

Possible typing error?

-31C is -23.8F, maybe interposed 23 and completely missed the negative sign?

That's probably it. I had that happen on a product listing once. Should have read -40F (which is what I submitted) and someone in the testing lab reported it as 40F.
I'd think Eaton would be on top of that.

 

[don_resqcapt19]

UL 489 permits a 50°C rise over a 40°C ambient for the line and load connection points and says the maximum permitted operating temperature of a non-metallic operating handle is 85° C.

 

[kwired]

That's probably it. I had that happen on a product listing once. Should have read -40F (which is what I submitted) and someone in the testing lab reported it as 40F.
I'd think Eaton would be on top of that.

Poorly written instructions and specifications are common with anything these days and doesn't surprise me at all. Is more understandable when some of this material originates in other countries, but yet go to our own schools and things have changed from when anyone over 35-40 was a still in school. We used to get docked on grades for misspellings and improper grammar even on a science report. Now even on English class assignments those mistakes are tolerated with no penalty, and we wonder why there is so much published material out there with so many grammatical and spelling errors in it, even newspapers and magazines are not as easy to read as they used to be because you have to decipher some of the mistakes.

I have a hard time reading posts sometimes on this site alone, but expect more mistakes on something like this. You won't find all that many spelling errors in my posts, I usually proof read before I submit - just something I learned to do when still in elementary school. I also try to use proper grammar, though it has been long enough since the time I would have been critiqued on it that I'm sure it has gotten a little rusty, and some slang always creeps into casual type conversation anyway.

I am not a English major by a long shot, but I do see the need to try to better use those skills that seem to be lost so that we can more effectively communicate. Face to face verbal communication is not the same as reading written content. There is no emotion in written content, you need more detail to get what the writer intended to mean in what was written, and simple mistakes just complicate things, you don't know if they were in a hurry, plain don't care, or are just ignorant to such things.

 

[romex jockey]

UL 489 permits a 50°C rise over a 40°C ambient for the line and load connection points and says the maximum permitted operating temperature of a non-metallic operating handle is 85° C.

Thank you Don...

UL489

I suppose we'd need to $$$ to view any of it's contents...

~RJ~

 

[mgookin]

...

I am not a English major by a long shot, but I do see the need to try to better use those skills that seem to be lost so that we can more effectively communicate. Face to face verbal communication is not the same as reading written content. There is no emotion in written content, you need more detail to get what the writer intended to mean in what was written, and simple mistakes just complicate things, you don't know if they were in a hurry, plain don't care, or are just ignorant to such things.

That should read
"I am not a English major by a long shot, but I do see the need to try to better use those skills that seem to be lost so that we can more effectively communicate. Face to face verbal communication is not the same as reading written content. There is no emotion in written content. You need more detail to get what the writer intended to mean in what was written, and simple mistakes just complicate things. You don't know if they were in a hurry, plain don't care, or are just ignorant to such things."

:lol:

Just kidding on the critique there!

Our local newspaper was putting out trash you would not believe. It started a few years ago. Many of us on their forums were bashing them saying "What's with this trash?...We can't even understand what you're trying to say... You're supposed to be a professional journalist...You expect people to pay for this?"

We finally dialed them in. I'd say they're around 98% grammatically correct now.

Professional translation is a huge industry. It's like teaching. The teacher knows nothing about the subject but is a "professional teacher" and the same goes for the translator who used to drive a cab in Shanghai and now drives one in NYC. He's just not up to par on ambient temps of a CH BR and he never will be.

 

[rt66electric]

found an article ....

found an article ....

http://www.schneider-electric.us/si...ang=en&locale=en_US&id=FA173839&redirect=true


Schneider Electric: the global specialist in energy managementUnited StatesUnited States[Change country][Global Website] Home Site map Contact


Frequently Asked Questions



How hot can circuit breakers get? What is the temperature of a molded case breaker?
Issue:
How hot can circuit breakers get? What is the temperature of a molded case breaker?

Product Line:
UL489 listed molded case circuit breakers

Environment:
UL489 standard - June 2011
This article is intended to be a summary and may contain errors. Please see the most recent publication of the UL489 standard for complete details.

Cause:
Circuit Breaker is hot to the touch.
A thermal graph from a testing agency that indicates the breakers are white hot.

Resolution:
The acceptable operating temperature of a circuit breaker is defined by UL in the UL489 standard (June 2011), which is listed below.

Terminations for standard rated breakers: Paragraph 7.1.4.2.2 says the temperature rise on a wiring terminal at a point to which the insulation of a wire is brought up as in actual service shall not exceed 50°C (90°F).

Terminations for 100% rated breakers: Paragraph 7.1.4.3.3 says the temperature rise on the termination shall not exceed 60 deg. C (108 deg. F).

Handles, knobs and other user surfaces: Paragraph 7.1.4.1.6 says the maximum temperature on handles, knobs, and other surfaces subject to user contact during normal operation shall not exceed 60°C (140°F) on metallic and 85°C (185°F) on nonmetallic surfaces.


Table 1: Summary of temperature rise and maximums for a standard rated breaker (breakers are calibrated in 40 deg. C ambient):
Surface:
Temp. – Rise above ambient
Temp. – Max. at 40 deg. C ambient (104 F)
Termination on standard rated breaker
50 deg. C (90 F)
90 deg. C (194 F)
Termination on 100% rated breaker
60 deg. C (108 F)
100 deg. C (212 F)
Handles, knobs, other user contact surfaces - Metallic
N/A
60 deg. C (140 F) Maximum
Handles, knobs, other user contact surfaces - Nonmetallic
N/A
85 deg. C (185 F) Maximum

The heat generators inside the breaker are the contacts and the bimetal, which are typically the hottest parts within the breaker, and the temperature in the current path gets cooler the closer to the bus or cable, the heat sinks. Therefore, the sides or bottom of the breaker can be hotter than the terminations. Each breaker family or frame will have its own heating characteristics due to different designs. Smaller frames tend to run hotter on the side of the breaker than do larger frames, since the side of the breaker is much closer to the heat generators within the breaker.

If your breaker is operating within the temperature rise and maximum values in Table 1, then the breaker should be operating normally.

If you still believe the breaker is suspect and are concerned that the breaker may nuisance trip, then I recommend you hire Schneider Electric Field Services (Square D Services) to primary injection test the breaker to determine whether or not the breaker performs per its Characteristic Tripping Curve.




I understand this is the "official table", but ,What has been your the real world experience???

 

[rt66electric]

I also found this.. on CH and BR breakers

I also found this.. on CH and BR breakers

https://www.carltonbates.com/static/catalog/products/images/PDF/EATON_b3102se.pdf





Type CH
The CH interiors feature 100% copper
bus and use the CH 3/4-inch wide
(19.1 mm) circuit breaker, which
minimizes panel space. Recognized
by contractors for its sturdy design,
the CH interior will appeal to those
customers seeking an industrial
quality bolted bus bar and the space
saving of 1/4-inch (6.4 mm) per bus
stab. With a typical 12 circuit CH
interior, this space savings amounts
to an 1-1/2 inch (38.1 mm) savings
over its 1-inch (25.4 mm) counterparts.
The stab rating of the CH interiors is
140 amperes maximum, meaning that
the handle rating of breakers mounted
across from one another may not
exceed 140 amperes.




Type BR
The BR interiors are manufactured of
formed, plated aluminum or copper,
and use the Cutler-Hammer Type BR
1-inch wide (25.4 mm) circuit breaker.
This design affords customers the
most circuit flexibility as many of
these interiors allow the installation
of standard 1- and 2-pole breakers
as well as duplex (2 poles in a 1-inch
space, 25.4 mm), or quadplex (4 poles
in a 2-inch space, 50.8 mm) breakers.
The stab rating of the BR interiors is
200 amperes maximum, meaning that
the handle rating of the breakers that
are mounted across from one another
may not exceed 200 amperes.

I found this article surprising, I always thought the "max breaker stab" ratings was a 100 amps