Copyright Goodheart-Willcox Co., Inc. 176 Essential Electrical Skills for HVACR: Theory and Labs The R × 1 range means most of the current flows through the shunt, leaving only a fraction of current to flow through the coil. As a result, pointer deflection is minimal. See Figure 10-8. In this example, the pointer is on the 1k mark. This is a small region with many increments, which can cause more inaccurate readings. The R × 100 range is a better choice for measuring a 1000 Ω resistor. With this range, less current flows through the shunt, thus allowing more current through the coil and more pointer deflection. Notice the pointer is about 60% of travel and points to 10. Because the increments are farther apart, there is higher accu- racy. Since the R × 100 scale is used, the marked value 10 is multiplied by 100 and results in 1000 Ω. All meters have a maximum value of resis- tance that can be displayed. The meter shown has a maximum value of 20,000,000 Ω per manufac- turer’s specification. The 20,000,000 is indicated by the 2k mark and using the R × 10,000 range (2000 × 10,000 = 20,000,000). Left of the 2k mark is the infinity symbol (∞) which indicates that the meter is out of range. A resistance greater than 20,000,000 would be displayed as infinity. See Figure 10-9. 10.2 The Digital Meter A digital meter is a device that displays electrical quantities as a numerical value rather than a position on a meter. Digital pertains to only two states: zero and one. Digital electronics convert the analog information, or the analog signal, in long R × 100 range R × 1 range 1000 Ω resistor measured using R × 1 and R × 100 ranges Goodheart-Willcox Publisher Figure 10-8. Selecting the R × 100 results in better accuracy to measure the 1000 Ω resistor. Goodheart-Willcox Publisher Figure 10-9. Resistance greater than the meter’s maximum capacity is displayed as infinity. Infinity resistance