CompEx questions are organised into topic-based sets including Ex d, Ex e, Ex n and intrinsic safety. Select a subject to study at your own pace or complete a timed practice attempt.

“CompEx” contains 361 questions across 16 collections.

Learning

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Exam

A practice exam lasts up to 60 minutes and includes up to 50 questions from the selected collection. Correct answers and results appear after completion.

Sample questions and answers

These examples come from the published collection. Choose Learning to study questions in sequence, or Exam to check your knowledge.

The maximum resistance of the cables connecting a zener barrier earth bar and the main earth should not exceed?

One correct answer

1 Ohm✓ Correct answer
10 Ohm
1 MOhm
100 Mohm

1) Which one of the following locations may Ex ib equipment be used?

One correct answer

(I) EPL Gc (Cat 3G) only;
(II) EPL’s Gb & Gc (Cat’s 2G & 3G);✓ Correct answer
(III) EPL Ga (Cat 1G);
(IV) EPL’s Ga, Gb & Gc (Cat’s 1G, 2G&3G);

11) The recommendations for the inspection of electrical systems in hazardous areas are given in which one of the following standards?

One correct answer

(I) BS EN50017;
(II) BS EN60079-17;✓ Correct answer
(III) BS EN50014;
(IV) BS EN60079-14.

24) When IS and non-IS terminals are fitted in the same enclosure the minimum clearance between the live-parts of the two terminal types is required to be?

One correct answer

(I) 50mm;✓ Correct answer
(II) 40mm:
(III) 6mm;
(IV) 3mm.

The latest standards require that glands for Ex e and Ex n enclosures must be certified as meeting the requirements of IEC& BS EN60079-1

One correct answer

True
False✓ Correct answer
-

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