In Europe, to avoid concern over nuisance tripping due to optical sensors being fooled (an issue that does not affect the I-Gard product due to calibration and design criteria) pressure input is often used.
The pressure sensor detects a change in differential pressure caused by the pressure wave of an arc flash and reacts between 6-12 milliseconds, sending a trip signal. The pressure sensor can be used as a stand-alone product or be used in combination with the Sentri, DSP-ADM or ArciTec relays.
