Switchgear and switchboards

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zog

Senior Member
Location
Charlotte, NC
Jeez, this entire thread keeps dragging on with people wanting to argue that well defined, established and published industry standards are not valid, but loosey-goosey street slang or far flung foreign concepts that don't apply here are.

Enough already...
Yeah but some guy told me otherwise once in a bar during lunch,,,,,,,,,,,,,,,,,,
 

Mike01

Senior Member
Location
MidWest
Switchboard / Switchgear

Switchboard / Switchgear

It's all about the construction as posted earlier UL and ANSI standards that the equipment is buit to switchgear is more rugged and flexible one advantage is that switchgear constructed to the ANSI standard is braced for 30cycles allowing you added flexibility when it comes to selectivity, where all panelboard and switchboards UL-891 & PB-2 are only rated for 3 cycle interruptering.
 
T

T.M.Haja Sahib

Guest
It's all about the construction as posted earlier UL and ANSI standards that the equipment is buit to switchgear is more rugged and flexible one advantage is that switchgear constructed to the ANSI standard is braced for 30cycles allowing you added flexibility when it comes to selectivity, where all panelboard and switchboards UL-891 & PB-2 are only rated for 3 cycle interruptering.
I think even ICCB (MCCB also) has only 3 cycle interrupting rating and so cannot be used in a switchgear.
 

Strathead

Senior Member
I was only asking you to clarify WHAT is your statement "I disagree" refers to? That qualifies - in your book - as being a jerk? Woww
I was not referring to the one clarification you asked for, I was referring to the dismissive and curt responses throughout the thread. You seem like a smart guy, so I assume your intention was to come across the exact way that you did. Sure and all knowing. However, from a reader standpoint, it comes across as smug and all knowing. As I stated, I hear switchgear used every week as a generic term for all distribution equipment on a typical commercial project. I am pretty sure I used to hear it referred to this way in California also. I assume that you and Zog must hear the term used this way as well. As such I would have expected the courtesy here of understanding and had a distinction made between the common use (or misuse) of the term and the meaningful definition. Are you saying that you are not familiar with people using the term switchgear to refer to the collection of distribution equipment? If that is honestly so, then I withdraw the jerk comment. If it is not so, then yes, that qualifies as being a jerk in this instance.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
It's all about the construction as posted earlier UL and ANSI standards that the equipment is buit to switchgear is more rugged and flexible one advantage is that switchgear constructed to the ANSI standard is braced for 30cycles allowing you added flexibility when it comes to selectivity, where all panelboard and switchboards UL-891 & PB-2 are only rated for 3 cycle interruptering.
What advantage is there in allowing a short circuit to continue for 1/2 second? Is this just to allow the downstream stuff time to clear?
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
Retired Electrical Engineer - Power Systems
Is this just to allow the downstream stuff time to clear?
Pretty much.

For many decades, it seemed thsr philosophy was; damn the consequences, save the electrical gear. Maybe electrical equipment was more difficult (expensive?) to replace than buildings and process equipment. but, I think this came from the utilities whose purpose in life is to supply power until the downstream fault burns itself clear.

Nowadays we tend to want to minimize downstream damage and arc fault incident energy so we rarely let faults go past a few cycles. Of, course there are a few situations where the extra 'withstand' time is good to have.
 

Mike01

Senior Member
Location
MidWest
I think even ICCB (MCCB also) has only 3 cycle interrupting rating and so cannot be used in a switchgear.
I never indicated MCCB or ICCB type devices in switchgear assemblies. Typically when one discuss switchgear (low voltage less than 600V) based on industry standard it would consist of ANSI construciton gear with low voltage draw out type circuit breakers (LVPCB's) not ICCB or MCCB however switchboards can have a number of different types of devices inclduing but not limited to MCCB & ICCB type devices.
 
I was not referring to the one clarification you asked for, I was referring to the dismissive and curt responses throughout the thread. You seem like a smart guy, so I assume your intention was to come across the exact way that you did. Sure and all knowing. However, from a reader standpoint, it comes across as smug and all knowing. As I stated, I hear switchgear used every week as a generic term for all distribution equipment on a typical commercial project. I am pretty sure I used to hear it referred to this way in California also. I assume that you and Zog must hear the term used this way as well. As such I would have expected the courtesy here of understanding and had a distinction made between the common use (or misuse) of the term and the meaningful definition. Are you saying that you are not familiar with people using the term switchgear to refer to the collection of distribution equipment? If that is honestly so, then I withdraw the jerk comment. If it is not so, then yes, that qualifies as being a jerk in this instance.
I know what I know and I also know what I don't know. The later not with the same certainty as the former.

I hear misuse of terms all the time, in most/all cases from people who are outside of their area of knowledge, trade or profession. On this forum - maybe poliannashly - I expect a level of professionalism that such FUNDAMENTAL terms are used and understood properly and if that is not the case, people willing to learn and acknowledge so.

I do not have a problem people viewing me as smug or arrogant. It is THEIR problem, not mine. Same with projection of 'jerk'. It has been proven that when people call others names it is a projection of their own qualities that thye have been unable to make and inner peace with. As Popeye famously said: I yam what I yam.:lol:
 
It's all about the construction as posted earlier UL and ANSI standards that the equipment is buit to switchgear is more rugged and flexible one advantage is that switchgear constructed to the ANSI standard is braced for 30cycles allowing you added flexibility when it comes to selectivity, where all panelboard and switchboards UL-891 & PB-2 are only rated for 3 cycle interruptering.
Mike, I believe that the withstand(time) rating of construction and the interrupting cycle rating of the breakers are two different areas of rating.

ICCB's ARE rated to be used in ANSI rated LV switchgear. AFAIK MCCBs are not, they are only allowed in switchboards.
 

Strathead

Senior Member
I hear misuse of terms all the time, in most/all cases from people who are outside of their area of knowledge, trade or profession.
But, to beat a dead horse. That is not the case in this instance. I here the term "switchgear" to represent the entire distribution package from the Square D representative, the Siemens Representative other Journeymen and Master electricians, and many with less credentials. As far as I know, these are not, "people who are outside of their area of knowledge". I don't like being wrong, which I know I was, but I prefer to be educated rather than dictated to. More often than not, people on this site are courteous enough to explain.
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
Retired Electrical Engineer - Power Systems
But, to beat a dead horse. That is not the case in this instance. I here the term "switchgear" to represent the entire distribution package from the Square D representative, the Siemens Representative other Journeymen and Master electricians, and many with less credentials. As far as I know, these are not, "people who are outside of their area of knowledge". I don't like being wrong, which I know I was, but I prefer to be educated rather than dictated to. More often than not, people on this site are courteous enough to explain.
As an industry there is often overlap in the terms we use. Context means everything.

You are correct, that switchgear (lower case) is an accepted general term for electrical distribution equipment. Others are also correct that Switchgear (upper case) is a type of equipment built to specific standards.

As a general term, switchgear is usually used when referring to the 'main' equipment (either service entrance or transformer secondary) regardless if it is a Switchboard, Switchgear, or even Multi-metering.
 
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