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Transformer comparisons
Eight pairs of terms that get used interchangeably and should not be. Each one is a side by side table and a straight answer about which you actually need.
Power transformer or Distribution transformer
What separates a power transformer from a distribution transformer, by voltage, size, loading and where each one sits on the grid.
Step up or Step down
What a step up transformer does, what a step down transformer does, and why the same unit can often do both.
Single phase or Three phase
When a job needs a three phase pad-mounted transformer and when a single phase unit will do, with the cost and capacity differences.
Pad mounted or Pole mounted
Why underground service uses a pad-mounted transformer and overhead service uses a pole mount, and what that means for cost.
Substation transformer or Pad mounted transformer
How a unit substation transformer differs from a pad-mounted transformer and which one a commercial job actually needs.
Switchyard or Substation
A switchyard switches, a substation transforms. The distinction matters when reading a one line diagram.
220 volts or 240 volts
Why the same circuit gets called 220 volts and 240 volts, and what the nominal US standards actually are.
Transmission or Distribution
Where the transmission network ends and distribution begins, and which transformers sit on each side.