Skip to main content

Transformer installation playbook

Goal​

Install a transformer with correct protection, clearances, and documentation.

Inputs you must know before you start​

  • Transformer type, rating, and listing details.
  • Primary and secondary system voltages.
  • Space and clearance constraints.
  • Protection device options and settings.

The path (in order)​

  1. Verify location and working space requirements.
  2. Confirm listing and installation instructions.
  3. Select primary and secondary protection per transformer rules.
  4. Install and terminate conductors with proper torque.
  5. Verify grounding and bonding for the system type.
  6. Document protection settings and labels.

This is​

A checklist for transformer installs that aligns protection and space requirements with equipment listings.

This is not​

A full design for power distribution or system coordination.

Inspection-ready checklist​

  • Working space and access verified.
  • Protection devices sized and documented.
  • Terminations torqued and recorded.
  • Grounding and bonding confirmed.
  • Nameplate and labels visible.

Worked example​

A small transformer is installed in a dedicated electrical room. The crew verifies working space, sizes primary and secondary protection, torques terminations, and labels the equipment for inspection.

Cross references​

  • Primary: 450.3
  • Secondary: 110.3(B), 110.26, 250

Related