iSTS Static Switch type B4 - 100Amp 3 phase / 4 poleSKU: 150B43P40100
Static Switch type B4
Type: B4 3P4 100A
A Static Transfer Switch (STS) provides your critical load , equipment with an alternative supply source, thus increasing and improving power reliability and availability.
The Model B4 is a 4 pole, three phase 4RU 19-inch rack mount STS. Both the active conductor and the neutral are switched. Thyristors are used to undertake the switching process. These are many times faster and more reliable than their electromechanical equivalents.
The STS continuously monitors the supply sources and should the presently connected supply fail or degenerate to not be useable, the critical load is automatically and transparently transferred to the alternate source.
This switching process is undertaken as a break before make transfer. The break in the supply transition is so short that it is not seen by the critical load.
This is preferable to a make before break (or overlapping) changeover because when the two supplies are different and connected together large and unpredictable currents would flow between the sources degenerating both supplies and therefore the supply to the critical load.
In case of downstream fault the STS will not transfer the fault to the alternate supply even if the voltage is adversely affected. Once the fault current has cleared the STS will resume normal operation protecting the critical loads from voltage disturbances, (10 second settling time).