UL 508a - Industria Control Panel

Hi all!
I'm trying to certify my company with the UL 508a standard, I'm having troubles with one step of the certification, it's with the SCCR calculation.
Has someone done this calculation before ? Hope you can help me with that and maybe have a room in Microsoft Teams for a better comprehesion.
Thanks.
 
Hi all!
I'm trying to certify my company with the UL 508a standard, I'm having troubles with one step of the certification, it's with the SCCR calculation.
Has someone done this calculation before ? Hope you can help me with that and maybe have a room in Microsoft Teams for a better comprehesion.
Thanks.
If you're referring to the SCCR of the control panel, rather than “calculating” its SCCR it actually only requires that you investigate the fault capacity of the relevant components and then identify the ones with the lowest SCCR rating (the weakest link in the circuit). The SCCR of that component is the SCCR of the entire panel assembly. I make a one-line sketch/drawing of the panel's >200V electrical circuits and add the SCCR rating of each component on the drawing. You can then easily and verifiably determine the panel's rating. More info is here: https://electricalengineeringresour...current-ratings-in-industrial-control-panels/
 
If you're referring to the SCCR of the control panel, rather than “calculating” its SCCR it actually only requires that you investigate the fault capacity of the relevant components and then identify the ones with the lowest SCCR rating (the weakest link in the circuit). The SCCR of that component is the SCCR of the entire panel assembly. I make a one-line sketch/drawing of the panel's >200V electrical circuits and add the SCCR rating of each component on the drawing. You can then easily and verifiably determine the panel's rating. More info is here: https://electricalengineeringresour...current-ratings-in-industrial-control-panels/
If you are attempting to join the UL 508A ICP program, then I assume you are aware of the training and certification testing. Each manufacturing location must maintain at least one UL 508A qualified manufacturer technical representative (MTR) on staff who can effectively interpret and accurately apply the requirements of the UL 508A industrial control panels Standard. If you really want to learn how to do the calcs, the last 4 hours of the MTR 12 hour training are dedicated to SCCR calculations. If you just want the answer, then follow Boston automations previous post (it will get you there a whole lot faster).
 
Can someone please help me!! I am currently preparing for MTR exam for UL 508a Panel shop. I have a doubt about SCCR calculation. Suppose we have a Class J fuse in Branch circuit as the first OCPD and below that fuse we have motor protection, a control relay and a motor. The sccr rating of the fuse is 200kA, Motor protection is rated at 65kA and Control relay at 5kA. In this case do we have to consider the peak let through of the Fuse and modify the SCCR of the total branch circuit or is it OK to take the lowest value of the SCCR i.e. 5kA of the control relay? Thanks a lot in advance.
 
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