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 Post subject: Does all equipment have SCCR?
PostPosted: Wed Jun 10, 2026 3:14 pm 

Joined: Thu Dec 18, 2025 3:21 pm
Posts: 22
Im relatively new to studies learning as I continue school.

When modeling equipment and checking submittals and spec sheets, I often find it hard to locate the SCCR. Does all equipment come with an SCCR? If not, would you use a default of 5k or 10k?

Specifically, at this moment I am modeling some power line filters for a data center job. I dont see any ratings for the power line filters beyond voltage, current, and hertz

what do you do if SCCR is not listed?


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 Post subject: Re: Does all equipment have SCCR?
PostPosted: Mon Jul 06, 2026 9:29 am 
Arc Level

Joined: Mon Jan 18, 2010 11:35 am
Posts: 615
Location: Wisconsin
I would use 5kA for hardwired devices. I think this is the default value that UL assigns to electronics like VFDs.


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 Post subject: Re: Does all equipment have SCCR?
PostPosted: Fri Aug 07, 2026 1:34 pm 
Sparks Level

Joined: Fri Sep 28, 2018 7:32 am
Posts: 61
Location: Sioux Falls, SD
Overcurrent protective devices will have an AIC. Assemblies (panelboards, switchboards, control panels, etc.) will have an SCCR. Per NEC it shall be marked...but this is not always done. For some equipment you can follow the guidance of the standards such as components listed in UL 508A Table SB4.1. This provides assumed maximum SCCR values for VFDs, motor controllers, breakers, and other items.

Equipment manufactured by big names like Schneider, Siemens, Eaton, etc. will always be marked.


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 Post subject: Re: Does all equipment have SCCR?
PostPosted: Fri Aug 07, 2026 1:36 pm 
Sparks Level

Joined: Fri Sep 28, 2018 7:32 am
Posts: 61
Location: Sioux Falls, SD
JBD wrote:
I would use 5kA for hardwired devices. I think this is the default value that UL assigns to electronics like VFDs.


UL 508A Table SB4.1 lists the following for VFDs

0-50HP 5kA
51-200HP 10kA
201-400HP 18kA
401-600HP 30kA
601-900HP 42kA
901-1600HP 85kA


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