【Daily Quiz 075】Basic Knowledge of Control Systems

Thread Content

This post was last edited by oatobnus on 2009-11-18 10:15. Single-choice question: 1. Under the same differential pressure, what is the name of the throttling device that results in the greatest pressure loss? ( ) A) Nozzle B) Orifice plate C) Venturi tube 2. When using a thermocouple with a k-type rating and its corresponding compensation wire to measure temperature, but if the polarity of the compensation wire is reversed in the wiring, the instrument’s indication (). A) Too large B) Too small C) It may be large or small, depending on the specific circumstances. 3. How are the constant-value control system, program-controlled system, and follow-up control system classified? () A) According to the structure of the automatic control system B) According to the characteristics of the automatic control system C) According to the pattern of change in the set value 4. What is commonly used for low-noise control valves? A) Single-seat valve B) Sleeve valve C) Diaphragm valve D) Angle valve. 5. Determine which of the following control objects has the greatest lag. ( ) A) Tank level; B) Temperature of the direct steam heater; C) Pipeline pressure; D) Pipeline flow rate. True or False: 6. When a fluid is in motion, there is no exchange of particles between streamlines, and the trajectories follow an orderly, well-structured pattern; such flow conditions are referred to as turbulent flow. 7. Generally, thermistors are used to measure the temperature of media with lower temperatures, while thermocouples are used for media with higher temperatures. 8. The ASCO solenoid valves with single control have a self-locking function, while those with dual control do not have this function. 9. In a cascade control system, the main loop is a follow-up system, while the secondary loop is a constant-value control system. 10. Thermal resistors do not require cold-junction compensation when measuring temperature. Answer key: BCCBC – Wrong, Right, Wrong, Wrong, Right.