Electrical Power Systems Technology

64 Electrical Power Systems Technology

cal-control applications as well. Memory and storage type instruments are
available for use for more sophisticated measurement purposes.

Numerical-readout Instruments
Many modern instruments employ numerical readouts. These simpli-
fy the measurement processes and permit more accurate measurements
to be made. Numerical-readout instruments rely upon the operation of
digital circuitry in order to produce a numerical display of the measured
quantity. They are very popular measuring instruments.

Figure 3-3. Schematic diagram of a Wheatstone bridge

Figure 3-4. Construction of a cathode ray tube