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BLACK&VEATCH <br /> CONFERENCE MEMORANDUM <br /> City of Decatur, IL B&V Project 66558.405 <br /> Nitrate Removal Facility B&V File G-1. <br /> Switchgear Modifications July 16, 2001 <br /> Meeting held on July 13, 2001, at WTP, in Decatur, IL. <br /> Recorded by: Stephanie L Kelemetc <br /> Attending: See attached sign-in sheet <br /> The main goal of the meeting was to find a solution to the switchgear modifications that would <br /> maintain the integrity of the redundant system and meet all code requirements. Modern Electric's <br /> Change Notice No. 1, issued on June 26, 2001, was previously submitted to the electrical <br /> inspector and several items were questioned. The discussions can be summarized as follows: <br /> 1. Bus transition sections. The bus transition sections are non-standard engineered pieces of <br /> equipment which do not have a UL listing. A field listing would most likely be required by the City. <br /> This is an additional charge. There was also a question as to whether the design group has had <br /> past experience on this type of equipment. This could be confirmed with the group but B&V has <br /> used this arrangement on previous projects. <br /> 2. Feeder sections. The NEC tap rule limits the distance between the tap and overcurrent <br /> protection for the new feeder to 25 ft. Placing the new east section at the west end of the lineup <br /> would violate this rule. There is not another good location that would let you maintain both the <br /> 25 ft distance and the working clearances unless the maintenance storage area is taken out of <br /> service. <br /> 3. Overcurrent protection. The NEC requires that the feeders need to be provided with the <br /> appropriate overcurrent protection. Cutler-Hammer is proposing that a fused latched contactor is <br /> used for overcurrent protection. It will act as a non-load break switch. The equipment is also <br /> much smaller than the vacuum-clad switchgear.. <br /> 4. Egress. The existing electrical room presently has only one point of egress. A second point of <br /> egress will be furnished during the engine-generator project. <br /> Even if the above concerns are alleviated, the modifications that will need to be done to the <br /> existing switchgear make this proposal less than desirable. Several solutions were discussed. <br /> The first was to tap the bus at the main or tie in order to eliminate the transition sections and <br /> reduce the distance between tap and protective device. This may not be possible due to the <br /> limited space in the bus compartments. <br /> Another possible solution would be to tap one of the existing feeders. The breakers are rated for <br /> 1200 amps and the maximum seen on any feeder is around 150 amps. This is not desirable from <br /> a maintenance stand point. Opening of that breaker will lose the feed to both distribution points. <br /> This breaker becomes the weak link in the redundant system. <br /> The most desirable option, and the one that B&V will ask for a proposal on, involves directly <br /> tapping the secondaries of the existing plant transformers. Fused latched contactors witl be <br /> located in the electrical room to provide primary overcurrent protection. This will also meet the <br />