HPS Drive Isolation Transformers are designed to meet the rugged demands of both AC and DC variable speed drives and also to provide the required voltage change. The separate primary and secondary windings provide electrical isolation between the incoming line and the SCR load. The windings are designed to withstand overcurrent of 150% of the rated load for 60 seconds or 200% of the rated load for 30 seconds. A duty cycle of one start for every two hours is permitted.