Robot Building for Beginners, Third Edition

CHAPTER 4 ■ DIGITAL MULTIMETER

Figure 4-13. Meter transitioning through logic states

Figure 4-14. Rubber boot (edge cover) for meter

Memory

Similar to the memory feature available on most calculators, memory mode on a multimeter can store
one or more measured values. When only a single value is frozen and stored elsewhere on the display, this
feature is simply another name for data hold. Some multimeters have a multi-memory feature, but it’s not
terribly useful except in graphic scopes.

Relative

A relative mode shows the difference between the last value measured and the current value. This shows the
change in value, rather than the absolute value. Some multimeters have this feature.

Offset

An offset mode shows the difference between the value stored in memory and the current value being
measured. Some multimeters have this feature.

Limit Testing/Compare

A limit mode displays whether the measured value exceeds a specified maximum or minimum value stored
in memory. Some multimeters have this feature.

Holster or Rubber Boot

A rubber boot (see Figure 4-14) protects the meter from scuffs and bumps that might otherwise damage or
crack the meter’s primary case. The meter is almost always operated with the boot installed, unless space is
a serious issue.