Unswitched

With or without Disconnect Switch
With or without Ground Switch

Switched
(Single Step or multiple steps Tuned to single or, multiple frequencies)
Oil Switches
Circuit Breakers Fixed
Drawout

Vacuum Switches (Available with zero voltage closing)

Manual

Automatic (P.F., VAR, Voltage, Current, Time, and Temperature)

Iron Core Dry Type Single Phase
-Three Phase

Oil Filled Iron Core (Normally used on 23 to 35 kv systems)
-Single Phase
-Three Phase

Air Core

Harmonic filter banks are connected in either delta or floating wye to prevent harmonics from contributing to system ground problems.

-PT (Neutral to Ground) for Floating Wye Banks.
-CT (Between Neutrals) for Split Wye Banks.
-CT on phases for Delta Connections.