For Transferring Power Between two Sources with Ability to Bypass
Switches may be configured for open- or closed-transition transfer. For either configuration, if the
primary source is lost, the control initiates an open-transition transfer to the emergency source by tripping the breaker from the primary source and closing the breaker to the emergency source.
For open-transition transfer, once power has been restored, retransfer to normal is accomplished by reversing this process — first tripping the breaker from the emergency source and then closing
the breaker to the primary source.
For closed-transition retransfer to the normal source, the RPTCS control’s power monitoring functions ensure that both sources are within an acceptable window of synchronism before effecting a closed-transition retransfer to the normal source by first closing the normal source breaker and then opening the emergency source breaker.
Adjustable Center-Off Time Delay
In open-transition transfers between two live sources where large inductive loads are involved, induced voltage transients can result in a lack of synchronism between the sources, causing a bump upon transfer. A time delay between the opening of the primary source breaker and the closing of the secondary source breaker allows these voltage transients to decay. This center-off delay is factory preset at 3 seconds, but can be adjusted via the RPTCS control.
Center-off positioning is ideal for load- shed control schemes.
Manual Bypass/Isolation Capability
Allows Emergency ATS Bypass, Maintenance and Testing Russelectric® RTS Series Medium-Voltage Circuit-Breaker Bypass/Isolation Switches provide all the functions of an automatic transfer switch plus the ability to bypass power from a live source to load in the event the transfer switch becomes disabled. In addition, they are designed to allow isolation and de-energization of the automatic transfer breaker for maintenance, testing, or repair.
Selectable Load-Break or No-Load-Break Bypass
Operator can easily choose between load-break bypass or no-load-break bypass by means of a selector switch on the front of the control cubicle.