Basic Instrumentation Ch 4

Question 1

Spring-loaded regulators are popular because they are simple, light in weight, and require little maintenance?

a) True
b) False

Answer 1

a) True

Question 2

Large changes of the flapper in front of the nozzle cause changes through the full range of the controller is why use a nozzle and flapper on a controller

a) True
b) False

Answer 2

a) False

Question 3

Name two types of air relays

a) solenoid
b) continuous bleed
c) hydraulic
d) non-bleed

Answer 3

b) Continuous-bleed

d) Non-Bleed

Question 4

To achieve and increase in movement and actuate the flapper in a proportional controller which method should be considered?

a) Throttling range
b) proportional action
c) the action of the measuring means
d) negative feedback

Answer 4

c) the action of the measuring means

Question 5

A better solution for mechanical reset for a device is to have it reset manually rather than automatically

a) True
b) False

Answer 5

b) false

Question 6

List four modes of controlling

a) non-proportional
b) on-off
c) proportional-plus-reset
d) proportional-plus-reset-rate
e) off-off
f) proportional band

Answer 6

b) on-off
c) proportional-plus-reset
d) proportional-plus-reset-rate
f) proportional band

Question 7

Proportional action work is achieved when it positions the valve in proportion to change in the controlled variable

a) True
b) False

Answer 7

a) True

Question 8

Pneumatic controllers for commercial applications usually are of what capability

a) proportional band
b) on-off
c) proportional-plus-reset-plus-gate
d) none above

Answer 8

c) proportional-plus-reset-plus-gate

Question 9

A Booster relay is used to overcome response lag due to long connecting lines between the controller and valve

a) True
b) False

Answer 9

a) True

Question 10

A basic pneumatic positioner uses what two things?

a) Fixed orifice
b) auxiliary relay
c) globe
d) nozzle and diaphragm pressure
e) solenoid

Answer 10

a) Fixed orifice

d) nozzle and diaphragm pressure