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CHAPTER 5
process has been carried out within a certain expected time
or in a certain sequence.
The sensing devices used in poka-yoke systems can include
physical contact-sensing devices, energy-sensing devices, and
devices that sense changes in physical conditions.
In addition to the sensing devices themselves, poka-yoke
systems often include devices that link to the sensors. These
devices detect abnormalities in the system that might cause
an error, or they transmit information about errors. Sound
usually calls attention to the problem more quickly than a
light does. When a light is used, the “summoning power”
of a ashing light is far gr