What you will learn
Read a loop diagram; verify cables and terminations; simulate and verify analog and digital loops end to end; raise and close punch items correctly.
Course syllabus
- 1. Documents
Reading the loop diagram
- 2. Cable verification
Continuity, insulation and polarity
- 3. Analog loops
Simulating and verifying an analog loop
- 4. Digital loops
Digital inputs, outputs and final elements
- 5. Punch list
Raising and closing punch items
Free lesson · 17m
Reading the loop diagram
A loop diagram is the single source of truth for one loop: the field device, the cable and core numbers, every junction box and terminal, the marshalling arrangement, the I/O module and channel, and the software tag.
Before you touch a screwdriver, walk the loop on paper. Confirm the tag on the diagram matches the tag on the I/O list and the tag in the control system database. A mismatch between these three documents is extremely common on projects and is far cheaper to resolve at the desk than in the field.
Mark up your working copy as you go. The marked-up loop folder is a project deliverable and becomes the as-built record.
Loop diagram carries device, cable cores, junctions, terminals, I/O channel and tag; cross-check diagram, I/O list and database first; mark up as you go.