Protecting ballast circuitry against miswiring
AssigneeGeneral Electric Company
InventorLouis Robert Nerone
Life of this patent
Estimating the term…
Abstract
A circuit for protecting an electronic ballast for use with a remote controller for gas discharge lamps against miswiring to a power source. Depletion mode MOSFETS are employed in both sides of the circuit to the controller and the MOSFETS respond to overvoltage, including polarity reversal to create an open circuit condition in the circuit to the controller.
Claims16
A method of protecting an electronic ballast for a gas discharge lamp comprising:
- (a) connecting a voltage interface circuit intermediate the control circuit and the electronic ballast;
- (b) disposing a voltage responsive switch in circuit with each side of opposite polarity of the circuit;
- and,
- (c) automatically opening one of said voltage responsive switches when one of (i) an overvoltage condition occurs and (ii) the controller is connected to a reverse polarity power source.
A circuit for protecting an electronic ballast with controller for use with a gas discharge lamp comprising:
- (a) a voltage interface circuit powered by the ballast and connected intermediate the ballast and controller;
- and,
- (b) a voltage responsive series switch disposed one on each opposite side of the line between the interface circuit and the controller, wherein one of the switches is operative to open automatically upon the occurrence of one of (i) an overvoltage at the controller connection and (ii) a reverse polarity connection to a power source.
A circuit for protecting an electronic controllable ballast for use with a gas discharge lamp comprising:
- (a) a ballast interface circuit receiving power from the ballast and providing a relatively low voltage output for connection to a voltage controller;
- (b) at least one voltage responsive switching device disposed inline between the interface circuit and the voltage controller, wherein the voltage responsive switching device is operable, in the event the device is misconnected to a power source, to switch to an open circuit state upon experiencing one of (i) an overvoltage, (ii) a negative voltage greater than −2 volts.
Dependencies are inferred from the claim text.