True. Without a PROPER evaluation of the installation as a whole, anything you do is just guessing.
SCCR of control & starter panels
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True. Without a PROPER evaluation of the installation as a whole, anything you do is just guessing.
Facility SCCR?
Facility SCCR?
Okay, so we have a proper evaluation of our facility. Depending on which buss you tie to - the bolted short-circuit fault current ranges from 30kA to 70kA. Since rearranging equipment (our second business it would appear) precludes using buss impedance or any assumption as to which buss it will be on - Would it be proper to tell our OEMs for equipment to make 75kA SCCR panels?
We also install a buss disconnect with Bussmann LPS-RK fuses (300kA/600Vac) when installing machines.
Facility SCCR?
Okay, so we have a proper evaluation of our facility. Depending on which buss you tie to - the bolted short-circuit fault current ranges from 30kA to 70kA. Since rearranging equipment (our second business it would appear) precludes using buss impedance or any assumption as to which buss it will be on - Would it be proper to tell our OEMs for equipment to make 75kA SCCR panels?
We also install a buss disconnect with Bussmann LPS-RK fuses (300kA/600Vac) when installing machines.
You could tell them to build the control panel to have a 75KA SCCR and be covered no mater what, but that could add a lot to the cost that may not be needed. Since you are using RK1 fuses in the buss disconnect and all of your busses are less then 100KA, you could reduce the SCCR down based upon the size of the fuse you put into the disconnect. I would assume the fusing is based on the individual piece of equipment, so it would always be fused the same without regards to the buss it is connected to. For example, If you have a piece of equipment that requires 200A branch circuit protection and you use a LPS-RK-200SP, Per UL508A, table SB4.2, the panel would only need a SCCR of 22KA
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