Power monitor
OwnerGerald J. Byrnesinventor
Life of this patent
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Abstract
Electrical power lines connected to loads are monitored by a protective circuit assembly to suppress peak transient voltages and surges by use of a Zener clamping device. Impedance branches connected in parallel with the Zener device share the transient loads when Zener break-down occurs under abnormal conditions. Each impedance branch includes a non-linear resistor arranged to clip voltages at different levels, at least one of the branches having a fixed resistor connected in series with the non-linear resistor.
Claims8
A current shunting protection circuit connected to a source of line voltage including a plurality of parallel connected branches, voltage clamping means in a first of said branches for conducting current therethrough in response to line voltage exceeding a predetermined voltage breakdown value, non-linear impedance devices respectively connected in each of the other of the branches for establishing shunt paths therein under transient voltage conditions to clip peak voltages at different levels, and fixed impedance means connected in series with at least one of said non-linear impedance devices in a second of the branches for developing a volt drop across said second of the branches under normal peak voltage conditions that is less than said voltage breakdown value of the clamping means to prevent conduction of current therethrough, said non-linear impedance devices having impedances which decrease sharply when the line voltage exceeds said predetermined voltage breakdown value to share transient loads amongst said branches under transient voltage conditions.
Dependencies are inferred from the claim text.