Metering Equipment at Bombay Substation.

Franklin Times, Volume XXIV, Issue 139, 3 December 1934, Page 5

Metering Equipment at Bombay Substation.

BOARD’S METER FAULTY. WHAT TESTS REVEALED. DEFECTS REMEDIED At Tuesday’s meeting of the Franklin Electric Power Board, the engineer, Mr L. G. Sharp, presented the following report regarding the check metering equipment at the Bombay sub-station:— “When this metering equipment was first installed test sheets were not forwarded by the manufacturers and arrangements were made by the National Electrical and Engineering Co., to have it tested and calibrated by the Public Works Department of Hamilton, which issued a certificate stating that the meters were correct within the limits of accuracy specified by the manufacturers. In September, 1932, the Public Works Department was notified that a difference of 4.4 per cent was registered between the Department’s and the board’s meters. A claim was made in accordance with the provisions of the Power Supply Agreements which states that if a difference exceeding 2$ per cent exists between the two sets of meters both of them shall be tested by a competent person appointed by the Minister.. The Department then tested its own meters and claimed that they were correct.

Difference Not Explained.

“I wili explain that the testing waj difficult as the sets of meters operate on entirely different principles both arriving at the maximum demand in K.V.A. for a half hour s by different methods. As the Hamilton Department had tested both meters and could not explain why there was a difference of four per cent it was arranged that the testing officer fr,om the Department in Wellington should carry out independent tests. Slight alterations were made to both meters but the position was not changed much. The Department then agreed to purchase more modern and a better type of transformer which were recently installed at Bombay. About this time the board’s meter appeared to be erratic and it was thought advisable to arrange for an inspection and independent test. The National Electrical Go. agreed to have this done by the Wellngton City Corporation which employ an expert on metering equipment. “It was found after thorough test and examination that the meters were fitted with faulty jewelled bearings which although correct under most circumstances were capable of causing erratic readings. The Wellington Corporation fitted new jewels end carefully calibrated the instrument which was then re-erected at Bombay. An adjustment was made to the Department’s meters in October, 1933, slowing them one-half per cent. On account of a fault either having developed in the board’s meter or having existed from the beginning the board has not sufficient grounds to make a claim for a rebate on its power account. With the board’s permission I will interview the district engineer to see if it is possible to get the meters in closer agreement, but as the difference does not exceed 2£ per cent no allowance on the present power accounts can be expected.” The engineer’s report was received.