Ex o,q,m Systems

Question 1

What is Exo?

Answer 1

Use of mineral insulating oil to provide protection with fluid actually quenching the electrical ark or spark

Question 2

Rules of Exo

4

Answer 2

• Suitable for zones 1 and 2
• No live maintenance permitted
• Sealed enclosure IP66
• Potential hazard with old oil and PCB’s

Question 3

What is Exq?

Answer 3

This relies on the apparatus to be protected by having a sand or powder filling.

Question 4

Rules of Exq?

3

Answer 4

• Suitable for zones 1 and 2
• No live maintenance
• Minimum IP54

Question 5

What is Exm?

Answer 5

This is where you encapsulate hot or sparking components to prevent ingress of any explosive gas. Normally in resin.

Question 6

What is a disadvantage of Exm?

Answer 6

Apparatus that is encapsulated is not readily repairable and so needs replacing if broken. Usually used for low cost throw away items

Question 7

Rules of Exm?

2

Answer 7

• No live maintenance

- Only used in zone 1 and zone 2

Question 8

What are the sub categories of Exm?

Answer 8

mA, mB, and mC

Question 9

What is mA? (Exm)

Answer 9

May be used in areas requiring EPL Ga, Gb, Gc or category 1,2,3

Question 10

What is mB? (Exm)

Answer 10

May be used in areas requiring EPL Gb, Gc and category 2,3

Question 11

What is mC? (Exm)

Answer 11

May be used in areas requiring EPL Gc and category 3