Laserfiche WebLink
From: Susan Schiller sschiller@brph.com <br /> Subject: FW: Emailing: Study <br /> Date: Mar 13, 2018 at 7:55:24 AM <br /> To: Robert.Carey Robert.Carey@Kiewit.com <br /> Cc: Thad.Nelson Thad.Nelson@Kiewit.com, Clayton, Bradley D <br /> bradley.d.clayton@boeing.com, Poore, Paul <br /> Paul,Poore@jacobs.cam <br /> The following information is intended to address the requirements of the City of Everett electrical <br /> inspection for panel 4V24-2BJ7.5-D and its associated 1200A substation feeder and circuit <br /> breaker: <br /> 1. Ground Fault Protection of Equipment (NEC 215.10 and NEC 240.13): Please see attached <br /> for ground fault settings for the circuit breaker in the substation feeding panel <br /> 4V24-2BJ7.5-D. The settings shown on the attached time-current curve match the <br /> settings shown on the label on the circuit breaker in the substation in the factory. <br /> 2. NEC 240.87 Arc Energy Reduction: Please see below for explanation of code compliance. <br /> Susan Schiller PE <br /> Sr. Electrical Engineer <br /> EMAIL sschiller@ibrph.com <br /> CELL 206-499-2506 <br /> I 119020 33rd Ave W, Suite 530 I Lynnwood, WA 98036 I BRPH.com <br /> Named 2016 Best Company to Work For <br /> From: Kimitsuka,Richard[mailto:richard.khnitsuka@siemens.com] <br /> Sent: Monday,March 12,2018 8:26 PM <br /> To: Susan Schiller <br /> Subject: RE:Emailing: Study <br /> The instantaneous setting is 6600 amps. The minimum arcing fault current through the breaker is 8700 <br /> amps for scenario 4. <br /> The existing setting is lower than the minimum arcing fault current and complies with NEC 240.87 (B) <br /> Method to Reduce Clearing Time.One of the following <br /> means shall be provided: <br /> (1)Zone-selective interlocking <br /> (2)Differential relaying <br /> (3)Energy-reducing maintenance switching with local status <br /> indicator <br /> (4)Energy-reducing active arc flash mitigation system <br /> (5)An instantaneous trip setting that is less than the available <br /> arcing current <br /> If a maintenance setting is required,it can be set equal to the normal setting provided. <br /> CURRENT IN AMPERES <br /> 1000f <br /> a <br /> i <br /> i _ I 40-24 DMA eStAMSO <br />