Articles
Engineering notes and technical explainers
Technical articles from our engineering team on transformer component selection and maintenance.
2026-10-11
How Substations Are Designed
Substation design balances reliability against land and cost — the two biggest calls are air- or gas-insulated build, and how the busbars are arranged.
2026-10-05
What Is a Substation?
A substation changes voltage and switches power between lines, using transformers, switchgear and protection relays to keep electricity moving safely.
2026-09-29
What Is a Substation Battery For?
A substation battery keeps DC power available for protection, control and breaker-trip circuits when the AC supply is interrupted. Without it, a fault that trips the incoming feeders can leave the substation unable to trip its own breakers or re-energize.
2026-09-24
What Is a Transformer Oil Level Indicator?
A transformer oil level indicator watches the oil level in the conservator, the reservoir above the main tank, and raises an alarm if it drops below a preset point. It is the first, simplest check in a chain of protection that ends with the Buchholz relay.
2026-09-21
What Are the Main Types of Transformers?
Transformers are sorted three ways: by what they do to voltage (step-up, step-down or isolation), by grid position (power or distribution) and by cooling (oil-filled or dry-type). The third split decides which parts a transformer carries.
2026-09-18
What Is a Buchholz Relay?
A Buchholz relay is a gas-actuated safety device between a transformer's main tank and its conservator — it raises an alarm on a slow fault, then trips the transformer off supply before a fast one gets worse.
2026-09-12
What is a transformer bushing?
A transformer bushing lets a live conductor pass through a grounded tank wall without arcing to it — governed by IEC 60137, in oil-impregnated paper (OIP), resin-impregnated paper (RIP), or resin-impregnated synthetic (RIS).
2026-09-11
What partial discharge testing is, and when to run it
A small internal discharge that erodes transformer insulation over years, with almost no visible warning before it fails.