The technique introduced here to increase the upper limit of the resistance measurement of the digital multimeter is actually very simple: prepare a resistance slightly smaller than 20MΩ, and connect the resistance to be measured larger than 20MΩ in parallel with it. Use the R×20MΩ of the digital multimeter to measure the total resistance value of the two parallel resistors, and then calculate the resistance value of the resistor to be measured according to the parallel resistance formula.
The measurement error of this method is very small, and the maximum measurement range can reach more than 100MΩ.
