Module 1 · Lesson 1

Industrial electrical safety and isolation

Apply safe isolation, test-before-touch, permits, arc-flash awareness and controlled restoration of power.

Learning outcomes

Explain the key principles of industrial electrical safety and isolation.
Carry out a structured practical check or configuration task.
Recognise common faults, risks and evidence needed for diagnosis.

Before you begin

Isolation points, approved test instruments, PPE, permits and site procedures.

Safety: Use site procedures, approved test equipment and competent supervision. Never bypass a protection or interlock without formal control.

Step-by-step learning

Identify every energy source, including electrical, pneumatic, hydraulic and stored mechanical energy.
Isolate and lock out each source using the site lockout/tagout procedure.
Prove the tester on a known live source, test the circuit, then re-prove the tester.
Confirm the work area is safe, barriers are in place and the permit accurately describes the job.

Ian's practical tips:

Never assume a stopped machine is electrically safe. A PLC stop command is not an isolation.
Record isolation details and handover status whenever the job crosses a shift boundary.

Fault-finding questions

What should be happening, and what evidence proves it?
Where is the last known correct signal, voltage, state or process condition?
What changed immediately before the fault?
Can the system be divided into smaller testable sections?

Practical activity

Create a one-page test record for this lesson. Include expected values, measured results, equipment used, risks controlled, defects found and the final proven condition.

I completed the lesson activity. I checked the result safely. I can explain the fault-finding approach.