Tester for a plurality of circuit breakers having a range of rated currents and multiple trip functions
First Claim
1. A tester for testing a plurality of circuit breakers each having a line terminal, a load terminal and a designated rated current within a range of rated currents, the tester comprising:
- a plurality of load elements each having known fixed impedance;
an electronic switch associated with each load element connecting when turned on the associated load element in series with the load terminal of one of the plurality of circuit breakers under test and in parallel with any other load elements connected in series with the load terminal; and
a controller for turning on a number of the electronic switches selected to collectively draw through the associated load elements a combined test current selected as a function of the designated rated current for the circuit breaker under test and sufficient to trip the circuit breaker under test open.
2 Assignments
0 Petitions
Accused Products
Abstract
A tester for in situ testing of a plurality of circuit breakers having a range of rated currents and multiple trip functions, includes a plurality of power resistors of known impedance, an electronic switch associated with each power resistor connecting the resistor in series with the load terminal of the circuit breaker under test, and a controller that turns on a number of the switches selected to collectively draw through the associated power resistors a test current that is a function of the rated current and sufficient to trip the circuit breaker within a selected time window. Turn on of the electronic switches is also controlled to generate a current waveform appropriate for the trip function being tested. In a self test mode, the value of each of the power resistors is verified as being within limits.
26 Citations
14 Claims
-
1. A tester for testing a plurality of circuit breakers each having a line terminal, a load terminal and a designated rated current within a range of rated currents, the tester comprising:
-
a plurality of load elements each having known fixed impedance;
an electronic switch associated with each load element connecting when turned on the associated load element in series with the load terminal of one of the plurality of circuit breakers under test and in parallel with any other load elements connected in series with the load terminal; and
a controller for turning on a number of the electronic switches selected to collectively draw through the associated load elements a combined test current selected as a function of the designated rated current for the circuit breaker under test and sufficient to trip the circuit breaker under test open. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
Specification