Terminations
DO terminate cables to the correct points to prevent damage to the system
DO sleeve and terminate earth wires correctly
DO remain consistent in the allocation of wire colours
DO remember to attach cable and termination markers to aid maintenance
DO ensure that cable insulation extends right up to the throat of the terminal
DO ensure that there are no bare wires or wire strands
DO use the correct tool for crimp connections
DO pull test every one before termination
DO use the correct width terminal screwdriver to avoid cracking terminal blocks
DO ensure that terminal screws are adequately tight
Earthing
DO maintain separation of Safety, Instrument and IS Earths
DO ensure that earth continuity is maintained through field junction boxes
DO ensure that metallic outer enclosures are adequately earthed for safety
DO allow for any IS Barriers in systems with earth fault monitoring
RFI Screening
DO use suitably screened instrument cable for sensor runs
DO maintain separation of safety earths and screening
DO connect screening as advised by equipment manufacturers
DO ensure continuity through junction boxes/equipment housings
Lightning
DO keep instrument cables away from susceptible power and earth cables
DO fit surge protectors in areas subject to severe electric storms
Equipment
DON’T power up until commissioning
DO check area classification for equipment suitability
DO ensure correct IP rating for the environment
DO check power requirements
DO power from a separate fused spur (AC)
DO locate away from sources of heat
DO mount gas sensors in accessible locations, at the correct height
DO note position of end of line addressable sensor
DO mount at accessible working height for ease of commissioning and maintenance
DO protect the equipment from paint/steam and other contaminants
DO ensure easy access to the interior of the equipment
DO mount within easy reach and audible distance of operating personnel
DO protect from vibration
DO employ a combination sun and rain shield in all outdoor locations
DO power from a clean adequately rated AC/DC supply (no inverters fed from the same supply)
DO run cable within equipment enclosure away from components and circuit boards
DO keep cables within the equipment enclosure as short as possible
DO keep operating manuals adjacent to the equipment
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