What is the resistance reading at "5" on the megger scale shown in figure "A" of the illustration? See illustration EL-0044.
• How a megger insulation tester uses a non-linear analog scale with two sets of units (megohms on the left, ohms on the right) • How to match the numbered index marks (1–9) along the bottom with the curved resistance scale above them • The difference between megohms and ohms/kilohms, and which side of the scale the question is asking about
• Look at the pointer position at "5" along the bottom and trace straight up to see exactly which value on the upper resistance scale it lines up with. • Decide whether the value at that position lies on the megohm portion of the scale or on the lower ohm/kilohm portion. • Compare the value you read off the megohm part of the scale with the answer choices; pay attention to where the decimal point belongs (0.35, 3.5, 35, 350).
• Confirm that you are reading from the left-hand megohm scale, not the right-hand ohm/kilohm scale. • Verify which labeled tick marks (e.g., 2, 3, 4, 5 megohms, etc.) are just to the left and right of the vertical line from "5"; the correct reading should fall between them. • Double-check the order of magnitude (is it less than 1 megohm, a few megohms, tens of megohms, or hundreds of megohms?) before choosing among the options.
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