EPRI 2 Flashcards
A typical process control loop component would be which of the following A.sensor B.controller C.final control dvice D.all of the above
D. all of the above
A diamond on an instrumentation diagram encloses information about: A. calibration B.the set point C. controller action D.the power source
B. the set point
Central connection points for signal lines are called: A.instrument ports B.junction boxes C.input/output junctions D.field ports
B.Junction boxes
In a pneumatic loop diagram, tube and bundle numbers:
A. appear in rectangles
B.are wrriten on or near the signal line
C.appear in the notes section
D. are connected with a curved arrow to the signal line
B. are written on or near the signal line
In an electronic loop diagram, junction box connections are represented by: A.circles B.diamonds C.ellipses D.squares
D.Squares
On an instrumentation diagram, the loop identification:
A.consists of two, three, or four letters
B.is the same for all instruments in a specific loop
C.identifies the measured or initiating variable
D.appears in the upper portion of the instrument balloon
B. is the same for all instruments in a specific loop
Process instrument connection lines are indicated on an instrumentation diagram by: A.bold solid lines B.fine solid lines C.bold broken lines D. fine broken lines
fine solid lines
The thermostat for a central air conditioning system is set at 68 F. This value is an example of the : A.manipulated variable B.deviation C.set point D.controlled variable
C.set point
The statement ; “Thermocouple extension wires must have the same thermo electric properties as the thermocouple that they are used with,” is:
A. true, if the extension wires are submerged in the process fluid.
B. true, in all installations
C.false. extension wires must be made from either copper or brass
D.false. The type of extension wire makes no difference.
B.true in all installations
To convert the output from a thermocouple to a standard 4 to 20 mA instrument signal, a(n)\_\_\_\_\_\_ with cold junction compensation would be used. A.I/P Transducer B.P/I Transducer C.D/A Converter D.mV/I Transducer
D.mV/I Transducer
Iron constantan thermocouples are designated by the letter: A.T B.J C.B DS
B. J
To change the 4 to 20 mA analog signal from a transmitter to the signal required by a digital controller, a(n)\_\_\_\_must be a part of the instrument signal loop. A.I/P Transducer B.Signal condtioner C.D/P Transmitter D.A/D Converter
D. A/D converter
A device that changes a voltage signal to current signal is normally referred to as a(n): A.P/I Transducer B.E/I Transducer C.D/P Transmitter D.V/C Transmitter
B.E/I Transducer
A pneumatic control valve, without a positioner, is the final control element in a instrument loop. The tansmitter and controller are both electronic. In order for this control system to operate, a(n) \_\_\_\_\_\_ must be installed in the instrument signal line between the controller and the control valve. A.I/P Transducer B.MV/I Transducer C.D/A Converter D.P/I Transducer
A. I/P Transducer
The transmission signals considered standard for most instrument systems are A.4 to 20 psi and 3 to 15 mA B.0 to 24 volts and 0 to 20 psig C.3 to 15 psig and 4 to 20 mA D. 0 to 20 mA and 0 to 15 psig
C. 3 to 15 psig and 4 to 20 mA
A process is _______ if heat is produced by a reaction.
exothermic
A process is _____ if heat input is required to produce a reaction.
Endothermic
In most process control systems the final control element is : A. transmitter B.sensor C.controller D.valve
D.valve
A control vlalve with a direct acting actuator and direct trim will: A.fail closed B.maintain psotion C.fail open D.fail indeterminate
C.Fail open
A pneumatic valve actuator that operates over an instrument signal range of 9-15 psi is referred to as: A.split range B.fail safe C.air to close D.full range
A.split range
One significant advantage of single loop/stand alone digital controllers is:
A. Flexibility of configuration
B.4 to 20 mA input and output capability
C.internal I/P and P/I transducers
D.immunity to electrica surges and lightning strikes
A. flexibility of configuration
Hydrostatic head level can not be measured with a: A.dP cell B.resistance probe C.dip pipe D.pressure gauge
B resistance probe
RTD is short for:
Resistance Temperature Detector
What is a device that changes a voltage signal to a current signal?
E/I Transducer
