CONTAMINATION SAMPLE TAKING Clause Samples

CONTAMINATION SAMPLE TAKING. Concessionaire will prepare a contamination level verification program by taking samples for all those sections rated as Medium or High level, or in sections in which visual inspection has not been decisive. Sampling work will be carried out with de-energized lines, so the Concessionaire must coordinate the program to cut the lines' service with the COES, preferably coinciding with the cuts in periods for scheduled maintenance. The sampling procedure shall be as follows: a) Sampling is performed with the transmission line out of service, with presence of sunlight, absence of rain, low humidity and no strong wind. b) Samples are taken in portions from 60 to 100 m of conductor, of one of the three phases of the selected section. c) The conductor cleaning team collects contamination on the conductor's surface. d) The collected contamination is weighed in a precision scale expressed in milligrams. e) The contamination level (NC, in Spanish) in mg / cm² is determined, by applying the formula: Conductor surface is 2 r L, f) For insulator chains the sample of one of the bells will be taken, which visually shows the greatest contamination. The contamination level (NC) in mg / cm² is determined by applying the formula: g) The NC value is compared with values in Table 2 and the contamination level is determined in the conductors. h) The steps indicated in subsections c) to g) are repeated for the other sections of the line that require sampling. Sampling reports will be sent to OSINERGMIN. Contamination level values established in Tables1 and 2 may be revised at the request of OSINERGMIN and in agreement with the Concessionaire.