This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1881 edition. Excerpt: ...simple imperfection in the insulating sheathing, the ordinary conductivity test gives the correct result. It is advisable to keep a record of the conductivity resistance, so that it can be ascertained without the necessity of making a measurement. In the practical execution of this loop test, the ...
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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1881 edition. Excerpt: ...simple imperfection in the insulating sheathing, the ordinary conductivity test gives the correct result. It is advisable to keep a record of the conductivity resistance, so that it can be ascertained without the necessity of making a measurement. In the practical execution of this loop test, the connections being made as shown by the figure, all the plugs between B and C must be inserted; this is necessary, because the galvanometer connection is made on to the terminal B', which, is the same as B, instead of on to C. The test could be made byplacing the galvanometer on to C, but in that case we should, lose the advantage of the key, which it is always best to use. The plugs being inserted between B and C, and the other plugs being in their places, we should remove, say, the 1000 plug from between A and B, and having pressed down the left-hand key, to put the battery current on, which should be a zinc one as shown, we should adjust the plugs between D and E, pressing down the right-hand key as required until equilibrium is produced. The different resistances being inserted in the formula, y is found, which being divided by the conductivity resistance per mile of the cable, gives the position of the fault. For example. A cable 50 miles long, whose total conductivity resistance was 450 ohms, that is, 9 ohms per mile, was looped with a second cable, which had the same length and conductivity resistance as the first cable--the resistance of the loop being 450 x 2 = 900 ohms. The adjusted resistance in E A to obtain equilibrium was 4000 ohms, A B being 1000 ohms, then Dividing this by the conductivity per mile, which is 9 ohms, we get distance of fault from testing station = = 20 miles. In making a test of this kind it is advisable to use as...
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Add this copy of A Handbook of Electrical Testing to cart. $18.00, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
Add this copy of A Handbook of Electrical Testing to cart. $28.30, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
Add this copy of A Handbook of Electrical Testing to cart. $40.17, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2024 by Outlook Verlag.
Add this copy of A Handbook of Electrical Testing to cart. $56.28, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2024 by Outlook Verlag.
