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HomeMy WebLinkAboutCORRESPONDENCE - PURCHASE ORDER - 9191154 (2)Page 1 of 2 MEMORANDUM DATE: May 20, 2019 TO: Darin Atteberry, City Manager ________ THROUGH: Gerry Paul, Purchasing Director ________ Tim McCollough, Deputy Director, Utilities ________ Kraig Bader, Sr. Manager, Electric Engineering ________ FROM: Kent Coldsnow, Electrical Engineer I ________ RE: Request for Exemption to the Competitive Purchasing Process With S&C Electric, represented by The Peterson Company for Medium Voltage Padmounted Fault Interrupter Switches. Executive Summary The purpose of this memo is to request approval of an exception to the competitive purchasing process for medium voltage, sealed-tank, 5-way, padmounted fault interrupter switches used in the protection of the electric distribution system (stock number 6759-8022). Exception to Competitive Bidding Rationale In accordance with Code Section 8-161(d)(3), City Council approval is not required for exceptions less than $200,000. Code Section 8-161(d)(1)(b). Although there exists more than one (1) responsible source, a competitive process cannot reasonably be used, or, if used, will result in a substantially higher cost to the City, will otherwise injure the City’s financial interests, or will substantially impede the City’s administrative functions or the delivery of services to the public. Background and Justification Sealed-tank interrupter switches are designed for use where robust circuit-switching capability and reliability are of paramount importance. The expected function of the fault-interrupting sulfur hexafluoride (SF6) insulated switches is to operate in a fashion similar to a circuit breaker, and open the circuit when a failure occurs, protecting the electric distribution system and limiting the number of customers affected by a “downstream” fault. At this point, we have approved S&C as the manufacturer of the fault interrupting switches we are using in this application. Field experience and analysis of current switch designs has shown the S&C’s switches are the safest and most reliable for use in our distribution system. In the past, we have experienced significant problems with SF6-insulated switches manufactured by companies other than S&C. Financial Services Purchasing Division 215 N. Mason St. 2nd Floor PO Box 580 Fort Collins, CO 80522 970.221.6775 970.221.6707- fax fcgov.com/purchasing DocuSign Envelope ID: BFD7BBAB-C9B6-40FC-B3D6-AD4D95FA62E8 Page 2 of 2 G&W, the other major manufacturer from whom we have previously purchased switches, is unable to manufacture a quality switch. G&W’s switches have exhibited the following problems in our distribution system: 1) SF6 leakage – Loss of SF6 insulating gas pressure makes it unsafe to perform normal switching operations. This poses a safety risk to line crews who operate the equipment and to the general public if a fault occurs in the switch. SF6 leakage also poses a significant environmental concern. 2) False tripping – The protected taps on the G&W switches opened to protect the system from a fault that had not occurred. This creates unnecessary outages of significant proportions. In the case of large industrial and commercial customers, outages are also very expensive, so it is exceptionally important to avoid preventable outages caused by faulty equipment. 3) Failure to trip on confirmed through-faults – On several occasions, G&W switches did not operate during a fault condition which resulted in the upstream substation breaker operating. This dramatically increased the extent and length of the outages. Failure to interrupt known through-faults poses significant risks, as the intent of the fault interrupting switch is to limit fault energy to protect the line workers, public, and the electric distribution system. Again, outages of this nature can be very extensive, so it is important to limit the size of the outage only to the customers on the affected tap. G&W has not been cooperative about addressing these problems, and every repair effort is charged to the Utility as an additional O&M expense. S&C, the selected manufacturer for this item, has very good quality control and reliability of their switches has been exemplary. For that reason, S&C’s SF6 switches are the preferred equipment for fault interrupter applications in our distribution system. This equipment will be purchased directly from S&C’s representative, The Peterson Company. We are continuing to work with other manufacturers who have the potential to develop and provide fault-interrupting switches with similar functionality, but those companies have not yet met our functional and reliability requirements. Financial Impact Two to three switches with this particular configuration (3 switched ways, 2 protected ways) are placed in service each year, so the estimated cost per year is anticipated to be around $165,000. The expense related to spurious outages caused by nonconforming equipment, and the risk to the public and workers if equipment does not clear a known through-fault is far more than the risk of not having competitive bids on this product. Because there is also risk associated with having a single supplier for equipment in critical applications like this, we do intend to find a responsible and responsive supplier that can provide second source for these switches, but those manufacturers with whom we are in discussion have not yet yielded a competitive option. Recommendation Recommend approval of an exception to the use of the competitive bid or proposal in accordance with City Code Section 8-161(d)(1)(b) and 8-161(d)(2) and (3) which authorizes the City Manager to approve exceptions less than $200,000. The Purchasing Agent may use this approval, as authorized by City Code Section 8-161(d)(4), as the basis for negotiating the additional purchase of services from The Peterson Company, S&C’s authorized representative, for up to five one-year terms extending through May 2024. DocuSign Envelope ID: BFD7BBAB-C9B6-40FC-B3D6-AD4D95FA62E8