Questions and Answers
Which of the following would show where the power-distribution system, ducts, and manholes
are located for a manufacturing plant consisting of several buildings? Plot plan
Each motor in the plant should bear a metal tag with the __________ stamped on it
inventory number
Which of the following provides both overload protection and short-circuit protection in one
unit? Combination motor starter
If you close the contacts of a motor controller and measure a potential difference of zero between
the motor terminals, the fault is probably in the controller
Commutator overheating is sometimes caused by the direction of rotation of the motor being
changed without changing the position of the brushes to the new ____________ plane.
neutral
Worn or damaged ball and roller bearings are easily detected by the ____________ they produce.
unusual noise
The kind of lubrication that should be used in a bearing is determined by the bearing's
maximum operating temperature
, The two methods commonly used for changing the speed of a squirrel-cage motor using
mechanical starters are the reconnection method and the multiple-____________ method.
Cross-references to the different locations of limit switches in a diagram are provided by
arrows next to the symbol's line number
A helpful piece of information to have when revising a control circuit is the ____________ wire
or relay number. This information keeps you from having to hunt through the whole schematic
for it. last
If one phase of a three-phase, Y-connected winding is shorted, the ammeter will indicate a
higher current in the shorted phase
Maintained start-stop devices provide only undervoltage release
When preparing an elementary diagram, you should number all lines with __________ numbers
consecutive
The following symbol represents an ____________ outlet in a ____________. exit light;
wall
In addition to the locations of lighting and lighting panels, lighting diagrams show the locations
of telephone outlets