PS&C recently shipped an UPS system
with innovative load management. This innovation was part of the control logic installed in a ring bus UPS system
shipped by PS&C. Previously, a ring bus was configured with "X" modules with "X-N" modules required to support the total load. When the number of modules removed (for any reason) from the ring bus exceeds "N", the ring bus logic was required to split the ring bus. Splitting the ring bus puts part of the load on utility, while the remainder remains on the UPS. This happened because the PLC (Programmable Logic Controller)
must make a blind decision to split the ring bus whenever the number of modules supporting the load is less than "X-N".
This condition has been improved by the addition of PS&C's optional "Intelligent Load Management System"
for ring bus applications. By measuring the power required by each load node on the ring bus and measuring the output power of each module, the PLC
has a complete picture of available power and total load. With a complete picture the PLC can determine the actual number of UPS
modules required to support the actual load. It is not possible in a ring bus system to keep clean UPS power to the User's load under more scenarios due to PS&C's "Intelligent Load Management System"