Heater tolerance detection allows you to detect a failed heater or a heater that is beginning to fail. An alarm is triggered if the load current drops below or rises above specified levels.

For example, suppose you have four heaters that draw 25 Amps each, for a total load current of 100 Amps at 100 percent power. You could program the heater tolerance alarm to trigger if the load current drops below 75 Amps at 100 percent power. This would indicate that one of the heaters has failed (opened).

To monitor for a heater that is beginning to fail or age, you could watch for too little or too much current. In the example above, you might program the alarm to trigger if the load current drops below 90 Amps or rises above 110 Amps at 100 percent power.

The Power Series automatically adjusts the set points depending upon the percent power, as shown in the illustration below.