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Construction Documents <br />20052.02 / Orange County - Justice <br />Facility <br />26 0519 - 6 POWER CONDUCTORS AND <br />CABLES <br />1. All current carrying feeder phase conductors and neutrals shall be tested as installed, and <br />before connections are made, for insulation resistance and accidental grounds. This shall <br />be done with a 500 volt megger. In the procedures listed below shall be followed: <br />a. Minimum readings shall be one million (1,000,000) or more ohms for #6 AWG wire <br />and smaller, 250,000 ohms or more for #4 AWG wire or larger, between conducts and <br />between conductor and the grounding conductor. <br />b. After all fixtures, devices and equipment are installed and all connections completed <br />to each panel, the Contractor shall disconnect the neutral feeder conductor from the <br />neutral bar and take a megger reading between the neutral bar and the grounded <br />enclosure. If this reading is less than 250,000 ohms, the Contractor shall disconnect <br />the branch circuit neutral wires from this neutral bar. He shall then test each one <br />separately to the panel and until the low readings are found. The Contractor shall <br />correct troubles, reconnect and retest until at 250,000 ohms from the neutral bar to <br />the grounded panel can be achieved with only the neutral feeder disconnected. <br />c. The Contractor shall send a letter to the Engineer certifying that the above has been <br />done and tabulating the megger readings for each panel. This shall be done at least <br />four (4) days prior to final inspection. <br />d. At final inspection, The Contractor shall furnish a megger and show the Engineer’s <br />representatives that the panels comply with the above requirements. He shall also <br />furnish a hook-on type ammeter and voltmeter to take current and voltage readings as <br />directed by the representatives. <br />e. Results of the test shall be made available to the engineer at the required <br />pre-energization walk through. <br />2. Disconnect surge protective devices (SPDs) prior to performing any high potential testing. <br />Replace SPDs damaged by performing high potential testing with SPDs connected. <br />D. Correct deficiencies and replace damaged or defective conductors and cables and re-test as <br />indicated above. Contractor shall submit new test results to the Engineer to demonstrate the <br />deficiency has been corrected. <br />END OF SECTION 26 0519 <br />DocuSign Envelope ID: 09980A3B-0691-41B4-854D-3865F2287392