Active Intrinsically Safe Circuit

摘要

An active intrinsically safe circuit for detecting and mitigating non-compliance of current, voltage, power, or heat to at a load which resides in a hazardous area, where non-compliance may cause danger to life or harm to property. The intrinsically safe circuit monitors current, voltage, power, or heat, shuts off or otherwise limits current, voltage, or power. The intrinsically safe circuit then tests for return of compliance, and acts to restore current, voltage, and power to the load upon return of compliance.

主权项

1. An intrinsically safe apparatus for connection between a source of electrical energy and a load that receives the electrical energy, comprising
an active energy limiter allowing passage of the electrical energy to the load, wherein said electrical energy meets compliance criteria and establishing a compliant mode, and further maintaining said compliant mode while said compliance criteria is met, said active energy limiter operating to limit passage of the electrical energy to the load, wherein the electrical energy is noncompliant with said compliance criteria, and further establishing a noncompliant mode, a fault recovery circuit for intermittent restoration of passage of the electrical energy to the load, said fault recovery circuit being engaged upon establishment of said noncompliant mode, said fault recovery circuit further establishing a retest/recovery mode wherein said fault recovery circuit intermittently re-engages said active energy limiter and provisionally allowing passage of the electrical energy to the load for further testing according to said compliance criteria, thereby establishing a provisionally compliant mode, said active energy limiter operating during said provisionally compliant mode such that the electrical energy is again limited if the electrical energy is noncompliant with said compliance criteria, thereby by re-establishing said noncompliant mode, said active energy limiter operating during said provisionally compliant mode such that the electrical energy is fully restored when the electrical energy meets settable criteria, thereby re-establishing said compliant mode, and, said active energy limiter and said fault recovery circuit operating indefinitely.