摘要 |
<p>A transient voltage protection device, such as a transorb 50, is tested in service by connecting a voltage detector 60 in parallel with it in the circuit under protection. A switching device 40 provided between a voltage source 20 and a load 30 of the circuit is opened and a property of the voltage spike caused by the rate of change of current in the circuit inductance 21, 31 produced by opening the switching device is detected and used to determine the condition of the protection device. If the detected property of the voltage spike, such as its peak voltage, is not an expected predetermined value or within an expected predetermined range it may be assumed that there is a fault in the protection device. The transient voltage protection device may be a component of an aircraft circuit e.g. where the voltage source 20 is an engine generator.</p> |