Circuit recloser test set
AssigneeE.I.L. Instruments, Inc.
InventorPaul E. Schoen
Life of this patent
Estimating the term…
Abstract
A test set designed to energize an oil filled circuit recloser with a reasonably constant current to simulate fault conditions for the purpose of verifying the recloser operation as specified by manufacturer's performance curves is disclosed. The test set of this invention is a self-contained unit comprising a selectable tapped auto-transformer, a variable vernier auto-transformer, a selectable power resistance bank, an output transformer, a control package and a monitor package.
Claims14
A circuit recloser test set comprising:
- a primary circuit for producing a current-regulated voltage at its output said primary circuit including a power resistor bank of sufficient resistivity to minimize the effect of any impedance change in said circuit recloser under test,
- means for coupling said output of said primary circuit to a circuit recloser being tested;
- recloser monitor means coupled to said means for coupling said output of said primary circuit to a circuit recloser being tested;
- and
- control means coupled to said primary circuit and to said monitor means.
Apparatus for testing a circuit recloser having a variable reactance exhibited by a solenoid operated plunger therein, comprising:
- a source of test current including a variable transformer means for generating a group of discrete alternating current voltage levels within a selected range, means for adjusting each discrete voltage level within the range for fine adjustment, a series resistance bank having selectable resistances therein, and an output transformer for coupling test current from said source of test current to said circuit recloser, said output transformer having a primary winding which is serially connected to a selected value of said series resistance, and having the output winding thereof connected to the solenoid of said circuit recloser, said selected value series resistance having a resistance magnitude, as reflected through said output transformer, such that the variable impedance of an operating recloser is compensated for by the swamping effect of said series resistance, and
- means for monitoring the current flow to said circuit recloser from said output transformer.
A method of testing current operated electrical power switching equipment which exhibit a variable impedance during operation, comprising generating a selected voltage level which is adjustable over a selected small range, applying said generated voltage through a selectable power resistance bank of sufficient resistivity to swamp out the impedance change of said current operated electrical switching device and sensing and monitoring the current to said current operated electrical power switching equipement.
In an apparatus for testing a circuit recloser wherein actual fault current conditions are simulated to verify operation of said circuit recloser, and including means for producing and coupling to said circuit recloser simulated fault currents, monitor and control apparatus comprising,
- inductive sensing means for inductively sensing the simulated fault currents to said circuit recloser and producing an alternating voltage signal proportional thereto,
- means for converting said alternating voltage signal to a direct current voltage which is proportional to the true RMS value of said inductively sensed simulated fault current,
- means connected to said inductive sensing means for detecting when said alternating voltage signal rises above a selected voltage level and producing signals indicative of each transition to above and below said selected level,
- a storage means, and
- a gate circuit, connected between said storage means and said means for converting, for passing the direct current voltage proportional to the true RMS value of said simulated fault current to said storage means.
Dependencies are inferred from the claim text.