When the power can't fail.

Once a year is the working baseline for most commercial buildings. A thermal scan is usually where it starts, because loose connections and overloaded circuits both give off heat long before they cause an outage.

• Thermal scan for hot terminations and overloaded circuits
• Torque checks on connections
• Load readings and breaker condition
• Panel schedules verified against what is actually in the panel

Heavy motor loads, dust, humidity, or around the clock operation all shorten that interval.

A variable frequency drive arrives with generic factory settings. Startup is the work of configuring it for the motor and the machine it is actually running.

• Motor nameplate data and current limits
• Acceleration and deceleration ramps
• Control wiring and feedback
• Protection and fault settings

Manufacturers train and certify contractors to do this, and on many models the certified startup is what validates the warranty. A drive that skipped it will usually still run. It will also nuisance trip, run hot, and fail years early. SET is certified for startup on ABB and Yaskawa drives.

In California, any contractor or subcontractor on a state funded project has to be registered with the Department of Industrial Relations. It cannot be sorted out after award. An unregistered contractor cannot legally be listed on the bid, so the awarding body has to reject it.

• Prevailing wage on all covered work
• Certified payroll filed electronically with the DIR
• Apprenticeship requirements on qualifying jobs

SET is registered and has completed work on numerous schools and federal buildings.

It comes down to what failed and how old the drive is.

• Worth repairing: a cooling fan, a fuse, or a control board on a drive only a few years old
• Usually not worth it: a failed power stage on a fifteen-year-old unit, especially once the model is unsupported and parts come secondhand
• Check the capacitors: DC bus capacitors dry out with age and heat, so a drive that has run hot in a mechanical room for a decade is on borrowed time
• Watch for repetition: three failures is the application talking, not the hardware

Swapping a drive without looking at the load, the ventilation, and the parameter set tends to buy you the same failure again.

Mostly it involves not interrupting anything. The electrical work itself is often straightforward. The discipline around it is what makes the job different.

• Work scheduled into approved windows
• A written procedure signed off by facility operations before any panel is opened
• Badged access, escorted on site
• The A side and B side of a circuit never exposed at the same time
• Everything labeled to its source path as it goes in, because a mislabeled breaker becomes somebody's emergency two years later

Housekeeping counts for more than people expect, since dust and debris in a room full of air handling equipment is its own kind of risk.

The terms get used interchangeably and the hardware overlaps, but they answer different questions.

• Building automation controls the equipment: what runs, when, and at what setpoint
• Energy management measures and reduces what that equipment costs to run
• The controller layer underneath is largely the same in both cases

In practice the automation goes in first, and what it reports back is what makes energy management possible. Trying to do the second without the first is guessing.