25 marquee operators · 21 countries · verified roster
Bayer · Pfizer · TATA · Adani · JSW · ISRO · Siemens · Bosch · DuPont · Mahindra · Hindalco · and others
Every instrument loop traced from field terminal to DCS input card.
Loop folders go missing, spare cores get commandeered, and marshalling cabinets get re-terminated during turnarounds without anyone updating the drawing. We rebuild the loop set from a physical termination walkdown, the live I/O database and the marshalling schedule · drafted to ISA-5.4, cross-checked against your DCS configuration, and handed over loop-checked.
A loop diagram is the only document that shows the complete signal path · transmitter, junction box, marshalling panel, barrier or isolator, I/O card, DCS tag. Every one of those points is touched during a turnaround, and almost none of the changes get drafted. Spare cores get used and never recorded. Barriers get swapped for a different model with a different terminal arrangement. I/O cards get re-slotted when a channel fails. The result is that when a loop faults at 3am, the technician is troubleshooting from a drawing that describes a plant that no longer exists. Loop drawings are also the document a SIL verification depends on: you cannot prove a safety instrumented function’s architecture without a verified signal path.
CEng MIE India-signed deliverables · LiDAR-powered where applicable · digital twin handover ready · routes to the As-Built Engineering practice lead within 24 hours.
Existing loop folders, the DCS or PLC I/O database, the marshalling schedule and the instrument index are loaded and cross-matched. Loops present in the I/O database but absent from the drawing set are flagged first · those are the undocumented modifications.
Engineer-led walkdown opening field junction boxes and marshalling cabinets. Core numbers, terminal numbers, cable tags, barrier and isolator models and earthing arrangement recorded against each loop. Ex loops verified for IEC 60079-14 segregation and entity parameters.
Continuity and 4-20 mA signal traced from transmitter terminals through junction box and marshalling to the I/O channel. HART and fieldbus segments verified against the segment design. Mismatches between the physical channel and the DCS tag reconciled with your controls team.
Loops redrawn to ISA-5.4 with ISA-5.1 symbology, showing terminal-level detail, cable and core identity, barrier data, power source and I/O address. Drafted in AutoCAD or your native instrumentation platform to your site drawing standard.
Each rebuilt loop signed off against a loop check sheet. Deliverable set includes the loop diagram package, an updated instrument index, a marshalling cross-reference and a spare-core register so the next modification can be recorded properly.
Reports reference the international and national standards your regulators, F500 audit teams, and corporate process safety leads cite. Every deliverable signed by a Chartered Engineer (CEng MIE India).
Three landmark engagements from our verified roster · quantified outcomes, no client names disclosed without written permission.
1,180 loops rebuilt across three units. 94 loops had no drawing at all and 212 differed from the drawing at terminal level. SIL verification, stalled for eight months on unverified architecture, closed in six weeks.
Loop set rebuilt ahead of a DCS migration. 61 spare cores found in use and 38 I/O channels mapped to the wrong tag in the legacy configuration · corrected before cutover rather than discovered during it.
Loop diagrams for a sterile utilities block rebuilt to support requalification. Terminal-level evidence accepted by the inspector without a follow-up observation.
Tell us your plant, region, and scope · a named Chartered Engineer responds within 24 hours.