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With respect to the elevation, atmospheric pressure decreases approximately _____ for 1000 ft of the ascent
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The resistance value of RTDs increase with decrease in temperature:
Removal of latent heat will:
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______ is the number of positions an actuator will assume when the control signal is slowly changed 0 – 100%
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A mixing valve can also be used in a bypass application to control the flow through the coil by placing the valve _____ of the coil:
Typical voltage input ranges for sensor is _______ :
BALCO RTDs have which of the following element compositions:
Which of the following is sensors located in each main return air duct for controlling outdoor air/return mixing dampers or the outdoor air fans:
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Removal of _____ lowers the air temperature
_____ is the actual mass of water vapor in one cubic foot of air:
Type of signals from the controllers can be which of the following:
_____ temperature coefficient Thermistors are most commonly used for temperature measurement.
The error signal generated in closed loop system is fed to which of the following:
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In which of the control system sensor measures the control variable:
Which of the following is temperature measuring sensors:
In a microprocessor-based system, the sensor input is converted to which of the form
The difference between the temperatures at which the controller turns ‘on’ or ‘off’ is called the:
_____ is a standard protocol that allows control units from different manufacturers to pass data to each other.
When the velocity of the air in the duct reduces, the resulting velocity pressure difference gets converted to ______ pressure:
Valve characteristics for a typical cooling coil and a heating coil are same:
____ temperature is the sensible–heat level of air and is taken with an ordinary thermometer
In a Proportional controller when the measured value is greater than the set point, then the correction signal will be _____ :
Which one of the following control system is also known as “Feed Forward Control System”
While calculating the cooling load estimate for a house, each person is given an allowance of _____:
The effect of varying speed with a centrifugal pump is to vary which of the following quantity:
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The purpose of reheat coils in the air conditioning system is to _____ the relative humidity in the room when the sensible load comes down:
What part of the code allows the inspector to make rules concerning the reuse of equipment?
Oxygen depletion safety systems shall shut off the gas supply to the main and pilot burners when the oxygen in the surrounding atmosphere is depleted to the percent concentration specified by the manufactuer, but not lower than ______ percent.
