CompEx İmtahanı üçün Praktik Sualları
Practice Questions for the CompEx Exam
CompEx Sınavı için alışdırma Soruları
Nəzərə alın ki, bəzi sualların bir neçə cavabı ola bilər.
Cavabları sonuncu səhifədə tapa bilərsiniz.
1. Which of the following is not needed for a fire to take place?
a. Fuel
b. Oxygen
c. An enclosure
d. Spark of sufficient energy
2. Which of the following can ignite a gas atmosphere?
a. Electrical spark
b. Hot surface
c. Battery
d. Intrinsically safe circuit
e. Static electricity
f. Lightning
g. Vehicle
h. Friction
3. The temperature at which a gas ignites spontaneously is called:
a. Ambient temperature
b. Ignition temperature
c. Flash point
d. Thermal temperature
4. Which of the following are commonly adopted?
a. Zone 0, explosive atmosphere for more than 2000 hrs/year
b. Zone 0, explosive atmosphere for more than 1000 hrs/year
c. Zone 2, explosive atmosphere for less than 10 hrs/year
d. Zone 1, explosive atmosphere present between 10 and 1000 hrs/year
5. Which is an example of Group I gas?
a. Methane
b. Propane
c. Ethylene
d. Hydrogen and acetylene
6. The objectives of the ATEX Directive 95 are
a. Removal of technical barriers to trade
b. Incorporation of risk assessments
c. Standardization of 230V ac across Europe
d. Health and safety of workers
7. Concerning ATEX categories, which abbreviation is used for equipment?
a. IEC
b. APL
c. EPL
d. API
8. The term EPL stands for
a. Electrical Protection Level
b. Equipment Protection Level
c. Electrical Protection Load
d. Equipment Pressure Level
9. Ex `n` equipment can be used in
a. Zone 0
b. Zone 0 and Zone 1
c. Zones 0, 1 and 2
d. Zone 2
10. Equipment Protection Level `Gc`/Category 3 equipment can be used in
a. Zone 0
b. Zone 0 and Zone 1
c. Zones 0,1 and 2
d. Zone 2
11. Components which produce sparks, such as contactors and switches, are permited inside Ex `d` enclosures
a. True
b. False
12. Which Standard deals with the general requirements for the Ex`d` protection concept?
a. IEC 60079-1
b. IEC 60079-3
c. IEC 60079-14
d. IEC 60079-17
13. Flameproof equipments is so named because
a. An internal explosion is not permitted
b. An internal explosion is permitted
c. An external explosion is permitted
d. The enclosure is resistant to gas entering the enclosure
14. Ex `d` equipment can be used in
a. Zone 0
b. Zone 1 and 2
c. Zone 2 only
d. Zone 0 and 1
15. A switch is located in a flameproof enclosure less than 2 litres in volume in a IIC environment. The enclosure requires
a. Industrial glands
b. Ex `e` glands
c. Ex `d` Barrier glands
d. An indirect entry Ex `e` chamber fitted with stuffing glands
16. Increased safety Ex `e` apparatus is designed to contain an internal explosion
a. True
b. False
c. True, providing barrier glands are used
d. True, providing the IP rating is at least IP54
17. In general, Ex `e` equipment can be installed in
a. Zone 0
b. Zone 1 and 2
c. Zone 0, 1 and 2
d. Zone 2 only
18. Ex `e` equipment can be installed in are requiring
a. Equipment to EPL `Ga` and `Gb`
b. Equipment to EPL `Ga`, `Gb`, and `Gc`
c. Equipment to EPL `Ga` or Category 1
d. Equipment to EPL `Gb` and `Gc`
19. Ex `e` equipment must have an IP rating of
a. IP 54
b. At least IP 54, but location conditions may require a higher value
c. IP 44
d. At least IP 44, but location conditions may require a higher value
20. Locknuts on an Ex `e` equipment are
a. Always required
b. Never required
c. Required on clearance holes
d. Required on 10mm thick threaded entries
21. In general, Ex `n` equipment can be installed in
a. Zone 0
b. Zone 1
c. Zone 2
d. Clear areas
22. Ex `n` equipment can be designed for
a. Group II
b. Group IIA and IIB
c. Group IIA only
d. Group IIB only
23. Which is not a recognised Ex `n` method of protection
a. Type A Non-sparking
b. Type d Flameproof
c. Type L Energy limited
d. Type R Restricted breathing
e. Type C Sparking with hermetically sealed, enclosed break or encapsulated
24. When terminating a cable into an 8 mm thick type `n` metal enclosure with a threaded entry, which of the following is required?
a. Locknut
b. Star washer
c. IP washer
d. None of these
25. For Ex `n` restricted breathing, which one of the following must always be provided?
a. IP washer
b. L:ocknut
c. Earth tag
d. Threaded entry
26. Ex `ia` equipment can be installed in
a. Zone 0
b. Zone 1
c. Zone 2
d . Clear area
27. Galvanic isolators require
a. An intrinsically safe earth connection
b. At least two Zener diodes
c. A device providing electrical separation such as a transformer, relay or opto-coupler
d. At least three Zener diodes
28. Which of the following does not require an intrinsically safe dedicated earth?
a. Zener barrier with two Zener diodes
b. Galvanically isolated barrier
c. Zener barrier with three Zener diodes
d. Zener barrier supplying simple apparatus
29. What is the minimum distance between terminals for intrinsically safe circuits and terminals of non-intrinsically safe circuits?
a. 100 mm
b. 50 mm
c. 6 mm
d. 3 mm 30.
30. What is the minimum clearance to earth (intrinsically safe circuits)?
a. 100 mm
b. 50 mm
c. 6 mm
d. 3 mm
Answer(cavab):
1. c
2. a,b,c,e,f,g,h
3. b
4. b,c,d
5. a
6. a
7. c
8. b
9. d
10. d
11. a
12. a
13. b
14. b
15. c
16. b
17. b
18. d
19. b
20. c
21. c,d
22. a
23. b
24. d
25. a
26. a,b,c,d
27. c
28. b
29. b
30. d