Switchgear and switchboards

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New EE

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Can someone please tell me if the following scenario is considered a switchboard or switchgear. I have a 15kv primary switchgear that feeds a 1000KVA 480/277v transformer. After the transformer I have 3P1600A draw out main breaker enclosure. Could the 3P1600A main breaker enclosure be considered switchgear or would the proper terminology be a switchboard? Thanks.
 
Smart $

Smart $

Esteemed Member
Location
Ohio
New EE said:
Can someone please tell me if the following scenario is considered a switchboard or switchgear. I have a 15kv primary switchgear that feeds a 1000KVA 480/277v transformer. After the transformer I have 3P1600A draw out main breaker enclosure. Could the 3P1600A main breaker enclosure be considered switchgear or would the proper terminology be a switchboard? Thanks.
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Defintely switchgear... IMO ;)

Metal-Enclosed Power Switchgear. A switchgear assembly
completely enclosed on all sides and top with sheet
metal (except for ventilating openings and inspection windows)
and containing primary power circuit switching, interrupting
devices, or both, with buses and connections.
The assembly may include control and auxiliary devices. Access
to the interior of the enclosure is provided by doors,
removable covers, or both. Metal-enclosed power switchgear
is available in non-arc-resistant or arc-resistant constructions.
Click to expand...
 
S

Strathead

Senior Member
Location
Ocala, Florida, USA
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Electrician/Estimator/Project Manager/Superintendent
New EE said:
Can someone please tell me if the following scenario is considered a switchboard or switchgear. I have a 15kv primary switchgear that feeds a 1000KVA 480/277v transformer. After the transformer I have 3P1600A draw out main breaker enclosure. Could the 3P1600A main breaker enclosure be considered switchgear or would the proper terminology be a switchboard? Thanks.
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A switchboard is switchgear. That would be like asking is a Valencia and orange or a fruit?
 
zog

zog

Senior Member
Location
Charlotte, NC
Strathead said:
A switchboard is switchgear. That would be like asking is a Valencia and orange or a fruit?
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No, they are different. Per IEEE:

Switchgear: A general term covering switching and interrupting devices and their combination with associated control, instrumentation, metering, protective and regulating devices with associated interconnections, accessories and supporting structures used primarily in connection with the generation, transmission, distribution and conversion of electric power.

Switchboard: A large single panel, frame or assembly of panels, on which are mounted, on the face or back or both, switches, overcurrent and other protective devices, buses and usually instruments.

Switchgear and switchboard structures are built and tested to different standards: Switchgear to ANSI standard C37.20.1, UL standard 1558, and NEMA standard SG-5, switchboards to NEMA PB-2, and UL-891. Switchgear incorporates only low-voltage power circuit breakers (LVPCB) which conform with ANSI C37.13, NEMA SG-3 and are listed per UL-1066, whereas switchboards may include any combination of protective devices including insulated case (ICCB), molded-case circuit breakers (MCCB) listed per UL-489, fusible switches listed per UL-508 and 977 and power circuit breakers listed to UL-1066.

Best way to know the difference, Switchgear is designed for flexibility and maximum protection, switchgear generally costs 2x what switchboards do. Switchboards are designed to be low cost, usually use cheap MCCB's or ICCB's, and have very few features.
 
ron

ron

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Location
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Agreed. In addition in the field you can only tell by what the UL sticker says.

You can buy switchboard construction listed to UL 891 but have insulated and isolated sections, draw out breakers, etc, but it is still switchboard because it in not completely compliant with UL 1558 (Switchgear).


zog said:
No, they are different. Per IEEE:

Switchgear: A general term covering switching and interrupting devices and their combination with associated control, instrumentation, metering, protective and regulating devices with associated interconnections, accessories and supporting structures used primarily in connection with the generation, transmission, distribution and conversion of electric power.

Switchboard: A large single panel, frame or assembly of panels, on which are mounted, on the face or back or both, switches, overcurrent and other protective devices, buses and usually instruments.

Switchgear and switchboard structures are built and tested to different standards: Switchgear to ANSI standard C37.20.1, UL standard 1558, and NEMA standard SG-5, switchboards to NEMA PB-2, and UL-891. Switchgear incorporates only low-voltage power circuit breakers (LVPCB) which conform with ANSI C37.13, NEMA SG-3 and are listed per UL-1066, whereas switchboards may include any combination of protective devices including insulated case (ICCB), molded-case circuit breakers (MCCB) listed per UL-489, fusible switches listed per UL-508 and 977 and power circuit breakers listed to UL-1066.

Best way to know the difference, Switchgear is designed for flexibility and maximum protection, switchgear generally costs 2x what switchboards do. Switchboards are designed to be low cost, usually use cheap MCCB's or ICCB's, and have very few features.
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J

jim dungar

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Location
Wisconsin
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PE (Retired) - Power Systems
Switchboard and switchgear have different construction standards and UL listings (e.g. UL891 for switchboards).

In general, the easiest to see differences are:
Switchgear has individual compartments for each breaker while switchboards may contain group mounted devices.
Switchgear is built with bussing area (which may be barriered) and rear cable compartments - swichboards have no clear defining point of cable and bussing areas.
Switchgear branch/feeder devices are breakers with drawout construction, switcboards may have fixed mounted or drawout devices (heck they can even have fusible devices)


Size of breakers, ratings of bussing, even physical size are not necessaily indicators of one construction or the other.
 
T

T.M.Haja Sahib

Guest
zog said:
No, they are different. Per IEEE:

Switchgear: A general term covering switching and interrupting devices and their combination with associated control, instrumentation, metering, protective and regulating devices with associated interconnections, accessories and supporting structures used primarily in connection with the generation, transmission, distribution and conversion of electric power.

Switchboard: A large single panel, frame or assembly of panels, on which are mounted, on the face or back or both, switches, overcurrent and other protective devices, buses and usually instruments.
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I do not know if switchboard and panel board are the same in which case devices, meters etc can only be mounted on the front side unlike a switch gear where both front and back sides may be used for this purpose.
 
S

Strathead

Senior Member
Location
Ocala, Florida, USA
Occupation
Electrician/Estimator/Project Manager/Superintendent
zog said:
No, they are different. Per IEEE:

Switchgear: A general term covering switching and interrupting devices and their combination with associated control, instrumentation, metering, protective and regulating devices with associated interconnections, accessories and supporting structures used primarily in connection with the generation, transmission, distribution and conversion of electric power.

Switchboard: A large single panel, frame or assembly of panels, on which are mounted, on the face or back or both, switches, overcurrent and other protective devices, buses and usually instruments.

Switchgear and switchboard structures are built and tested to different standards: Switchgear to ANSI standard C37.20.1, UL standard 1558, and NEMA standard SG-5, switchboards to NEMA PB-2, and UL-891. Switchgear incorporates only low-voltage power circuit breakers (LVPCB) which conform with ANSI C37.13, NEMA SG-3 and are listed per UL-1066, whereas switchboards may include any combination of protective devices including insulated case (ICCB), molded-case circuit breakers (MCCB) listed per UL-489, fusible switches listed per UL-508 and 977 and power circuit breakers listed to UL-1066.

Best way to know the difference, Switchgear is designed for flexibility and maximum protection, switchgear generally costs 2x what switchboards do. Switchboards are designed to be low cost, usually use cheap MCCB's or ICCB's, and have very few features.
Click to expand...

I respectfully disagree.
 
P

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
They often look quite similar to me, and have similar functionality. i think the only way to tell with any certainty is to look at what the UL Listing says it is.

Having said that, i have seen a fair number of things that are listed as MCCs or industrial control panels that are not that far off.
 
weressl

weressl

Esteemed Member
Location
Texas by the Gulf, geat crab, great shrimp
T.M.Haja Sahib said:
I do not know if switchboard and panel board are the same in which case devices, meters etc can only be mounted on the front side unlike a switch gear where both front and back sides may be used for this purpose.
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Not based on ANSI definition, which is what this forum is centered around. Now, granted that anything can be built, lets try to stay within the realm of reasonability and not stray into the garage-industry or Hindustan......
 
T

T.M.Haja Sahib

Guest
Keep it simple....

Keep it simple....

I only tried to help the OP to find the answer himself. Based on my previous post which is not really contradictory to IEEE definitions, here is the simple first clue.
A switchgear always has rear access for cable termination whereas a switchboard need not have it.
 
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T

T.M.Haja Sahib

Guest
weressl said:
That is incorrect. There are switchgears with front-only accessibility. Next?!
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In which case, look for the circuit breakers used in the switch gear having any short circuit current withstand short time rating also, whereas the breakers in the switchboard have only instantaneous trip settings.
 
T

T.M.Haja Sahib

Guest
weressl said:
That is also incorrect. I have purchased SIEMENS switchboard with the 1200A MCB having full range SS adjustable trips. Next?!
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Then you have to rely on what the manufacturer says about his product: Switchgear or switchboard. Simple.
 
T

T.M.Haja Sahib

Guest
I really do not know what I challenged. I only tried to get clarification on behalf of the OP.
 
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