TSC 900 TRANSFER SWITCH CONTROLLER
PM 151 REV 1 15/10/08 Thomson Power Systems
3.4.3. AUTOMATIC LOAD SHED OPERATION
The TSC 900 can be configured for automatic load shedding operation by use of a
programmable output contact. Under normal utility power conditions, the load shed
control is not activated. When an utility power failure occurs and the ATS transfer’s to
the generator supply, the load shed circuit is automatically initiated for a pre-
programmed time delay setting. Once the Load shed initiate timer expires, the Load
shed circuit is reset. Automatic Load shed can also be configured for automatic load
shed based on generator under frequency and/or ATS load kW (over power) set points.
Refer to Section 5.14 for programming instructions. The automatic sequence of
operation is further described as per the following flow chart.