________ valve bodies in general can be used on water service up to
temperatures of about 250°C. Ans✓✓✓ Cast-iron
__________ are used to convert physical quantities of flow, level,
temperature, pressure, and weight into electrical signals that represent
those quantities as accurately as possible.
a. Controllers
b. Control valves
c. Transmitters
d. Level switches Ans✓✓✓ c. Transmitters
403. The pressure differential across an orifice plate is measured by a
low-pressure connection before the plate and a high-pressure connection
after the plate.
a. True
b. False Ans✓✓✓ b. False
415. The measurement and control components of the system are
distributed at locations throughout the process area and perform two
functions at each location:
1) The measurement of analog and/or digital inputs
2) Control globe valves
3) View information transmitted from the processing area on an output
device such as a video monitor
, 4) Generation of output signals to actuators that can change process
conditions.
a. 1, 4
b. 1, 2, 4
c. 3, 4
d. 1, 2, 3, 4 Ans✓✓✓ a. 1, 4
A __________ is an excavation less than 3.7 m wide at the bottom, over
1.2 m deep, and of any length.
a. confined
b. excavation
c. hot work
d. trench Ans✓✓✓ d. trench
A Bourdon tube has an oval cross section, which is often shaped in the
form of a "C", having an arc span of about?
a. 360°
b. 180°
c. 270°
d. 90° Ans✓✓✓ c. 270°
A central foam distributing system for a process building consists of an
enclosure that houses a foam concentrate supply tank and a _____
device. Ans✓✓✓ Proportioning
,A circuit breaker is an automatic device that ______________________.
a. indicates circuit status
b. opens under abnormally high current conditions
c. provides a circuit junction box
d. A and B Ans✓✓✓ d. A and B
A circuit or load with a ______ power factor requires more current that
the same circuit or load with a power factor closer to 1.0 Ans✓✓✓ Low
A conductor's resistance to current flow is dependent on the following
factors Ans✓✓✓ Type of material, length, diameter and temperature
A confined space-testing program must consider _________________.
a. qualifications of testing personnel
b. test equipment which must be accurate and reliable
c. the confined space entry and exit points
d. A, B Ans✓✓✓ d. A, B
A controller compares the input signal, representing a
___________________, with a set point established by operations
personnel
a. Process variable
b. Controlled variable
, c. Cascade variable
d. Process pressure Ans✓✓✓ b. Controlled variable
A distributed control system cannot operate without which of the
following?
a. Programmable logic controllers
b. A communication network
c. RTUs
d. A single central control computer Ans✓✓✓ b. A communication
network
A dual supply system is one in which two independent power lines are
used to __________ the same load. Ans✓✓✓ supply
A fluidized bed of limestone will reduce ___ emissions Ans✓✓✓
Sulfur Dioxide
A fluidized bed of limestone, will not only reduce nitrous oxides but will
also significantly reduce sulphur dioxide emissions by the combination
of sulphur dioxide with the limestone. Ans✓✓✓ True
A lagging current means:
a. Voltage peaks before the current
b. The current is less than the voltage
c. The current peak precedes the voltage peak