In this paper, a power system having different loads which are switched at different instants is considered. We consider scenarios when the loads in a power system change at very fast rate. This switching causes impulsive noise in the associated power line communication (PLC) channel which limits the average bit error rate (BER) performance. The paper aims to analyze the performance of a PLC system for varying load switching rates. The PLC system under consideration employs direct sequence spread spectrum coding with amplitude shift-keying (ASK) modulation. An approximate closed form expression for the average BER is derived. A composite and a physical layer system model is developed. The physical layer model analysis shows that the average BER performance improves with increasing transmitted power and decreasing distance between the transmitter and the receiver. Similarly, the composite model analysis shows that the performance improves with decreasing load switching rates. © 2015 IEEE.