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SCCR Information for CEP9 Overload Relays

Question: Where can I find the SCCR information for CEP9 Overload Relays?

Answer: The installation instructions provided with each CEP9 sensing module list the SCCR values for each unit and are available in the Literature library.

This is the manner in which UL requires that the SCCRs for the CEP9 products be specified. The instruction sheets are reviewed by UL on a regular basis to ensure the information is correct. The specific SCCRs are defined in tables on pages 3 and 4 of the document. These tables are identical to what Sprecher + Schuh has published online and through other sales tools; however, the SCCR graphs should not be used to validate SCCRs in UL Listed industrial control panel or similar applications. UL must defer to the information shipped with the product.

Note that only the sensing modules are directly connected to the motor power circuit, so the SCCR information is pertinent to these modules; SCCRs are not necessary for the CEP9 control or communications modules.

While the CEP9 sensing modules are suitable for use with UL Listed circuit breakers rated up to 100 kA, 600V, the SCCRs when used with the KTU7-D Series circuit breakers are much lower due to the actual UL Listed ratings of these breakers; 600/347V, 25 kA and 480/277V, 65kA. The customer will need to make sure they are using the KTU7-D Series breakers in a wye system, not a delta.

In the case of applications utilizing magnetic instantaneous trip breakers/motor circuit protectors, UL standards (including UL 508A) stipulate that these devices can only be used when part of a UL Listed combination motor controller (Type D). Since Sprecher + Schuh does have a UL report covering the combination of the CAT combination starters with CA7 contactors and CEP9 overload relays, we have worked with UL to define the acceptable combinations of components in a spreadsheet available by request through Technical Support. In addition, we have added other motor controller combination types to allow customers access to increased SCCR ratings due to additional testing performed. 

It is important to note that the SCCRs defined in any supplied spreadsheet should not be considered the only acceptable SCCR ratings! The SCCRs either marked on individual contactors and/or overload relays, or on instruction sheets shipped with these devices are the first places to look for applicable SCCRs. The spreadsheet for UL should only be used as validation for using contactors and/or overload relays at SCCRs above the marked ratings.