What is a Load Break Switch in Pad Mount Transformers? (4/29/2024)

There are two main types of load break switches available in pad mount transformers: two-position load break switch and four-position load break switch.

Article - April 29, 2024 By LarsonElectronics.com

1 MVA Pad Mount Transformer - 34500Y/19920 Grounded Wye Primary, 400V Delta Secondary - KNAN/Bell Green

What is a Load Break Switch in Pad Mount Transformers?

Pad mount transformers are equipped with features that offer power management and control for operators. One of these features is a load break switch.

The Larson Electronics 50 KVA Pad Mount Transformer is an example of a unit with a four-position load break switch. Read on to learn more about this component.

Load Break Switch Function

A load break switch (LBOR switch) is an on or off switch designed for pad mount transformers. This switch can be turned on or off even when the transformer is energized. This makes them critical components for safely isolating the transformer for maintenance or repairs without interrupting service to customers on the other side of the switch.

This type of switch in pad mount transformers operates with a spring mechanism. The components are offered in various ratings, depending on the model or requirements of the electrical installation.

Load break switches are typically operated by utility personnel using insulated tools (hot sticks) from outside the transformer cabinet, minimizing the risk of exposure to high voltage. Some newer models may have an externally mounted switch with a viewing window for verification of isolation without opening the cabinet.

Types of Load Break Switch

There are two main types of load break switches available in pad mount transformers: two-position load break switch and four-position load break switch. A two-position load break switch is the most common type and functions like a simple on/off switch.

On the other hand, a four-position load break switch offers several options for the operator and is found in loop feed pad mount transformers. The positions include: A-side on and transformer on, B-side on and transformer on, A and B-side on and transformer on or A and B-side on with transformer off (bypasses the transformer).