Substations

LV Bushing

Typically made of porcelain, epoxy resin, or silicone rubber - low voltage bushings provide electrical insulation and a connection point for low voltage conductors as they enter or exit a transformer tank, maintaining electrical integrity and preventing arcing or short circuits.

Pressure Relief Device

Protects the transformer and surrounding equipment from damage or catastrophic failure due to internal pressure buildup, by helping prevent excessive pressure from building up inside the transformer tank during abnormal conditions like internal faults, overloads, or thermal runaway.

LV Arrester Mount

Commonly made of durable materials able to withstand environmental conditions and / or mechanical stress, they are designed to provide a stable and safe attachment point to securely hold low voltage arresters on a transformer.

Radiators

Often visible as the finned structures on the sides of top of a Substation tank, radiators are designed to dissipate heat generated by a transformer during operation. As substation fluid / oil heats as part of normal operation, heat is transferred to the radiator's surface and air blown by fans, or natural convection, carries away the heat.

Cooling Fan

Represented by either an axial fan or centrifugal fan, typically near or directly on the radiator of a transformer, they are meant to enhance the cooling efficiency of a transformer's radiator system. Their main purpose is to increase the airflow over the radiator fins during periods of high load or elevated temperatures.

Local Control Panel

A centralized interface for operators to monitor, control, and protect a substation transformer - housing various control, monitoring, and protection devices used to manage operation and withstand environmental conditions and mechanical stress.

Junction Box

Enclosure, or housing, serving as a secure, centralized point for connecting and organizing electrical cables, wires, and components related to a transformer's operation, control, and monitoring systems - while also protecting against moisture, dust, corrosion, and environmental hazards.

Pressure Vacuum Gauge

Measures, and displays, both positive pressure - pressure above atmospheric pressure - and negative pressure - vacuum conditions - within the transformer tank. Often integrated into a units control and monitoring systems, allowing for remote monitoring, data logging, and alarm notifications.

Winding Temp Gauge

Used to monitor the temperature of the transformer's windings, which are responsible for electrical insulation and power transfer. It provides essential information about the thermal conditions inside the unit and helps prevent overheating, insulation degradation, and potential transformer failures.

Fluid Temp Gauge

Continuously monitors the temperature of the insulating fluid - typically oil - inside a transformer tank to provide real-time feedback to operators. Usually installed on the tank itself and / or connected to temperature sensors immersed in the fluid within the unit.

Sudden Pressure Relay

Protective device typically installed on, or connected to pressure sensing devices inside the tank, meant to monitor internal pressure and detect sudden increases or decreases that could indicate abnormalities such as internal faults, gas accumulation, or mechanical issues.

Liquid Level Gauge

Utilizing a float mechanism that moves up and down with changes in oil level, the liquid level gauge provides accurate and continuous monitoring of the oil level in the transformer tank - which is crucial for insulation, heat dissipation, and overall performance.

N2 Gas Equipment

Refers to the use of nitrogen (N2) gas that can be used for various purposes - including providing inert atmospheres, cooling capabilities, moisture control, and leak detection functionality in a substation transformer.

Gas Fill Valve

Used to allow controlled filling of a transformer tank with insulating gas - such as nitrogen (N2), sulfur hexafluoride (SF6), or a combination of gases - to create a controlled atmosphere inside the tank, which helps maintain insulation properties, prevent oxidation, and enhance dielectric strength.

Tap Changers

Commonly, there are two types of tap changers than can either / or be utilized on a substation transformer.

De-Energized
Mechanism that operates by switching between different tap positions while the transformer is de-energized or not under load, and designed for switching taps during maintenance, shutdowns, or when the unit is offline.

On-Load
Enables the adjustment of a units turns ratio while it is still energized and in operation, typically controlled using microprocessor-based controllers, or relay-based systems to provide dynamic voltage regulation and flexibility.

HV Bushing

Typically made of porcelain, polymer (e.g., epoxy resin), or composite materials - high voltage bushings serve as a conduit for high-voltage conductors, such as cables or busbars, to enter or exit the transformer tank. They provide electrical insulation and a sealed passage for the conductors, while maintaining dielectric integrity and preventing electrical leakage.

Arrester Mount

Commonly made of durable materials able to withstand environmental conditions and / or mechanical stress, they are designed to provide a stable and safe attachment point to securely hold surge arresters on a transformer, ensuring proper positioning and alignment for effective surge protection.

Side Hand Hole

Access opening / panel located on the side of a transformer tank, providing safe and convenient access to visually inspect, perform maintenance, and access internal components of a unit without the need for complete disassembly or exposing the entire tank to the environment.

Drain Valve

Typically located at the bottom of the transformer tank, to allow gravity-assisted drainage, drain valves provide a means for draining or removing accumulated moisture or oil from a unit. Typically constructed from materials to allow for reliable operation even in challenging environmental conditions.