Motor Control Centre (MCC) Installation SWMS

Motor Control Centre (MCC) installation involves the delivery, positioning, mechanical alignment, busbar coupling, cable termination and pre-energisation testing of multi-section switchgear assemblies typically rated 400V–690V with prospective short-circuit currents exceeding 50kA. The work is classified as High Risk Construction Work under WHS Regulation 2011 r291 because it involves potential exposure to energised electrical installations, work in confined switchroom plenums, and manual handling of cubicles often exceeding 300kg per section. A Safe Work Method Statement is mandatory before any worker commences the task and must be prepared in consultation with the workers carrying out the activity per WHS Reg r39. The SWMS must remain accessible on site, be reviewed when controls fail or scope changes, and be retained for at least two years after any notifiable incident. This template addresses the specific switchgear, isolation, and lifting risks intrinsic to MCC commissioning across all Australian jurisdictions.

Hazards identified

7 hazards covered, sorted by priority.

Control measures

Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.

1. 1Elimination — Schedule MCC cubicle coupling and primary terminations before upstream transformer energisation so all conductors are dead and provably isolated at the source substation.
2. 2Elimination — Eliminate above-shoulder cable lifts by specifying bottom-entry gland plates and pre-fitting cable ladder transitions at floor level during design review.
3. 3Substitution — Substitute manual cubicle skating with hydraulic switchgear trolleys and air-skates rated for the cubicle mass to remove direct human pushing forces.
4. 4Substitution — Replace solvent-based cable lubricants with water-based polymer pulling compounds to reduce inhalation and dermal absorption hazards during termination.
5. 5Engineering — Apply AS/NZS 4836 lockout-tagout with caliper locks on upstream circuit breaker, test-before-touch with two-pole voltage tester verified against known live source.
6. 6Engineering — Install temporary mechanical earthing straps rated for prospective fault current at the MCC busbar prior to any conductor handling within the assembly.
7. 7Engineering — Provide forced mechanical ventilation delivering minimum 20 air changes per hour and continuous atmospheric monitoring (O₂, CO, LEL) inside the switchroom.
8. 8Administrative — Issue an Electrical Access Permit signed by the responsible electrical person, conduct pre-start briefing on this SWMS, and maintain a sign-on register.
9. 9Administrative — Limit termination shifts to four hours with mandatory rotation, exclusion zone barricading at three metres, and dedicated safety observer for all live-adjacent work.
10. 10PPE — Issue Category 2 arc-rated coveralls (minimum 8 cal/cm²), Class 0 insulated gloves with leather overgloves, arc-rated face shield, and Type 1 industrial helmet per AS/NZS 1801.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

On a regional wastewater treatment plant upgrade, a switchroom foreman convenes a pre-start brief at 06:30 in the site shed before three electricians enter the new pump station MCC room to terminate the incoming 400A submains and couple the final two cubicle sections. The foreman opens this SWMS on the site tablet and walks the crew through each hazard line. Identifying arc flash and inadvertent re-energisation as the controlling risks, he confirms the upstream ring-main unit has been racked out by the network operator, the caliper lock is fitted, and the test-before-touch sequence using a verified two-pole tester is demonstrated. The confined space hazard is addressed by switching on the temporary ducted ventilation and placing the four-gas monitor at low level near the cable trench, with a standby person nominated. Reviewing the manual handling controls, the team agrees to use the hydraulic switchgear trolley rather than skating the final cubicle by hand, and to rotate the cable terminator every ninety minutes. Each worker signs the SWMS register acknowledging the controls. Two hours into the task, an electrician notices the gas monitor alarm for low oxygen as the ventilation duct has kinked. Work stops immediately, the duct is straightened, atmosphere is re-tested, and the SWMS is annotated with the stoppage event and resumption time before termination resumes.

Related legislation

• WHS Act 2011 (model)
• WHS Regulation 2025
• AS 2865 — Confined spaces

Frequently asked questions