Throughout any Ex inspection campaign non-compliant issues are going to be found. Here are some common issues we have found whilst conducting inspections on Intrinsically Safe equipment
• Incorrect Zone (Zone 2 for Ex Ex ic; Zones 1 and 2 for Ex ib; Zones 0, 1 and 2 for Ex ia)
• Incorrect Group for hazardous area classification
• Incorrect Temperature Classification for hazardous area classification
• Incorrect ambient temperature range for environment
• Documentation missing or incorrect
• Certificate of Conformity not read
• Labels missing or not illegible
• No separation of IS and Non-IS circuits
• Entity calculations not checked correctly or incorrect values used
• Barriers swapped out and IS calculations not re-checked
• No dedicated IS earth/bar
• Earthing missing from Galvanic / Zener barriers
• Uncertified or incorrectly certified barriers installed in the hazardous area and no Conformity Assessment Document
• Screens not earthed at one end (preferable in the Non hazardous area) and not secured in terminals in the hazardous area
• Not correct maintenance
• Testing done with 230 VAC
• Inspection not focusing on Ex installations outside of hazardous area
• Ex i devices built into a U certified Ex d box
• Unauthorized modification on Ex i circuit
• Human failures, misuse
What others can you think of?
Source: https://www.haspecialists.com.au/blog/typical-problems-encountered-during-ex-i-inspections/ with some addings.
Keep up good work!