In my previous articles “Benefits from Calibrating Your Battery Tester” and “Unraveling Measurement Accuracy Specifications for Battery Testers,” I discussed how to apply measurement accuracy specifications and how to determine the size of the error term when making measurements. When describing these topics, I referred to a measurement system, whether that be a standalone measurement device like a digital multimeter (DMM), or an integrated measurement function, such as the current measurement subsystem integrated into your battery tester.
These measurement systems can provide improved capability by offering multiple measurement ranges. To understand multiple ranges, let’s first look at single-ranged measurement system for simplicity.