OXA100U3O3QB ABB TruONE 100 A UL 4-Pole Automatic Transfer Switch with Overlapping Neutral

Why Choose the ABB TruONE OXA100U3O3QB 100 A UL Automatic Transfer Switch?

The ABB TruONE OXA100U3O3QB, order code 1SCA153247R1001, is a 100 A UL automatic transfer switch (ATS) designed for automatic transfer of critical loads between two power sources. Part of ABB's integrated TruONE ATS platform, it combines the transfer switch, controller, sensors and operator interface into a purpose-designed automatic source-transfer solution.

This model features 4-pole construction with overlapping neutral (OLN) and open-transition switching. The overlapping-neutral arrangement ensures that the neutral conductor remains connected to the load during transfer from one source to the other, providing a make-before-break sequence specifically for the neutral pole while the power poles use open-transition operation.

The OXA100U3O3QB is an open-style, Level 3 control model with a 100 A UL current rating. It uses I-II operation without a stable OFF position between Source 1 and Source 2, and its bottom-entry configuration places both source connections at the bottom with the load connections at the top. ABB supplies a manual operating handle and a 2 m connection cable between the detachable HMI and ATS frame.

Key Advantages

• 100 A UL-rated automatic transfer switch for dependable source transfer.
• Integrated ABB TruONE ATS architecture combines switching and control functions into one platform.
• 4-pole configuration with an overlapping neutral pole.
• Open-transition transfer between Source 1 and Source 2.
• Overlapping neutral maintains the neutral connection to the load during source transfer.
• Level 3 controls provide advanced ATS control and monitoring functionality.
• Detachable HMI supports convenient commissioning, monitoring and operation.
• Manual operating handle included for appropriate local manual operation.
• 2 m HMI connection cable supplied as standard.
• Bottom-entry arrangement simplifies integration where source cables enter from below.

Key Features

• ABB TruONE automatic transfer switch platform.
• 100 A UL rated current.
• 4-pole configuration.
• 3-phase plus overlapping neutral switching arrangement.
• Open-transition source transfer.
• Overlapping-neutral (OLN) functionality.
• Neutral pole located on the right-hand side.
• Level 3 controller.
• I-II operation without a stable OFF position between Source 1 and Source 2.
• Open-style ATS construction.
• Bottom-entry configuration.
• Source 1 and Source 2 connections located at the bottom.
• Load connections located at the top.
• Detachable human-machine interface (HMI).
• 2 m connection cable between the detachable HMI and ATS frame included.
• Manual operating handle included.
• Approximate unit weight of 15.74 kg.

How Does the TruONE Overlapping-Neutral Transfer Function Work?

The ABB OXA100U3O3QB uses open-transition transfer for the main power poles while incorporating an overlapping neutral. During a transfer from one source to the other, the neutral pole is sequenced so that the neutral connection to the load is maintained rather than being disconnected during the transition. The overlapping-neutral pole is positioned on the right-hand side of the TruONE assembly.

This configuration is different from a conventional switched-neutral open-transition ATS in which the neutral may be disconnected during transfer. By combining OLN operation with ABB's integrated TruONE automatic transfer architecture, the OXA100U3O3QB provides a purpose-designed solution for installations requiring automatic source transfer while maintaining neutral continuity through the transfer sequence.

Typical Applications

• Automatic transfer between utility and standby-generator supplies.
• Critical-load power distribution systems.
• Commercial and industrial electrical switchboards.
• Emergency and standby power systems.
• Data, communications and control infrastructure.
• Building-services power distribution.
• Industrial facilities requiring automatic source transfer.
• Three-phase systems requiring overlapping-neutral transfer functionality.