The central component of every power transfer switch is its switching mechanism. In ASCO switches, essential components include electrical contacts, solenoid-driven operators, and features that mitigate electrical arcing and its effects. Transfer switch mechanisms are available in a range of ampacities and features that can be selected for specific applications. Key components of transfer switch mechanisms are labeled and described below.
The image shows a transfer mechanism from an ASCO H-frame switch. ASCO H-frame switches have rated ampacities of 600 to 1,200 Amps. This four-pole unit switches three-phase conductors and a neutral conductor.
- Arc Chute - are assemblies of steel plates that are installed near contacts on all UL1008-listed transfer switches. These plates draw the arc away from contacts. Arc chutes also break the arc into discontinuous segments to aid in the cooling and dissipation of the arc, when the associated energy is released as heat.
- Arcing Contact - Arcing contacts are a second set of mating electrical contacts that extend from main contacts. When loads are transferred, the arcing contacts close just before and open just after the main contacts. As the main contacts close or open, all current flows through the closed arcing contacts, where any associated arcing then occurs. Subcomponents are below:
- Solenoid Operator - Uses electrical power to drive the transfer mechanism.
- Main Contact Shafts - Rotate to move contacts in position. Subcomponents are below:
- Pole Cover - Protect switch against inadvertent contact with people and objects and prevent inter-pole arcing.
- Connection Terminal - Terminals for connecting power sources and loads to a transfer switch.
Supporting Information:
Transfer Mechanism Basics
Released for:Schneider Electric USA
The central component of every power transfer switch is its switching mechanism. In ASCO switches, essential components include electrical contacts, solenoid-driven operators, and features that mitigate electrical arcing and its effects. Transfer switch mechanisms are available in a range of ampacities and features that can be selected for specific applications. Key components of transfer switch mechanisms are labeled and described below.
The image shows a transfer mechanism from an ASCO H-frame switch. ASCO H-frame switches have rated ampacities of 600 to 1,200 Amps. This four-pole unit switches three-phase conductors and a neutral conductor.
- Arc Chute - are assemblies of steel plates that are installed near contacts on all UL1008-listed transfer switches. These plates draw the arc away from contacts. Arc chutes also break the arc into discontinuous segments to aid in the cooling and dissipation of the arc, when the associated energy is released as heat.
- Arcing Contact - Arcing contacts are a second set of mating electrical contacts that extend from main contacts. When loads are transferred, the arcing contacts close just before and open just after the main contacts. As the main contacts close or open, all current flows through the closed arcing contacts, where any associated arcing then occurs. Subcomponents are below:
- Solenoid Operator - Uses electrical power to drive the transfer mechanism.
- Main Contact Shafts - Rotate to move contacts in position. Subcomponents are below:
- Pole Cover - Protect switch against inadvertent contact with people and objects and prevent inter-pole arcing.
- Connection Terminal - Terminals for connecting power sources and loads to a transfer switch.
Supporting Information:
Transfer Mechanism Basics
Released for:Schneider Electric USA
