Nvent Services Gmbh

Chemelex Europe Gmbh

Mohammad Kazemi

Linda D B Kiss

Peter Martin

Edward H Park

Sirarpi Bicakci Jenkins

Paul Becker

Dan Caouette

Ganpathy Iyer

Jennifer Robison

Antonio Schettino

Linda Kiss

Constantine V Skidanenko

David Parman

Linda Db Kiss

A control system and methods for a digital circuit breaker are provided. The system comprises a digital circuit breaker, an electric trace heater electrically connected to the digital circuit breaker, a temperature sensor, and a controller device in communication with the digital circuit breaker and the electric trace heater. The controller device includes a processor in communication with the temperature sensor, and the processor is configured to receive a temperature value from the temperature sensor, construct a time-current curve for the digital circuit breaker based on the temperature value, and transmit data representative of the time-current curve to the digital circuit breaker.

Systems and methods for controlling digital circuit breakers

A heater cable produces a substantially level voltage across its cross-section, providing a uniform and controllable thermal output along its length. The heater cable includes at least one center bus wire extending axially along a central axis of the heater cable, and at least one radial bus wire extending axially through the heating cable and positioned adjacent to the center bus wire. The heater cable further includes a thermally and electrically conductive interstitial material disposed around the at least one center bus wire and the at least one radial bus wire, and a jacket disposed about the interstitial material, the at least one center bus wire, and the at least one radial bus wire.

Voltage-leveling heater cable

A self-regulating heater cable includes a PTC core formed of positive temperature coefficient material and disposed in electrical contact with at least two bus wires. The PTC core may encapsulate the bus wires and space the bus wires apart a predetermined distance via a connecting portion of the PTC core. The connecting portion has a tapered profile, and is thinner at the ends approximate the bus wires and thicker in a portion between the ends, which portion may be toward or at the center of the connecting portion. The thicknesses of the ends and the thicker portion are selected to produce a ratio that is within a range at which the heater cable produces heat at its outer surface with a substantially uniform profile, and primary heat generation of the heater cable has not shifted from the center of the connecting portion to the ends of the connecting portion.

Heater cable having a tapered profile

A self-regulating electric heater cable includes a monolithic heater core of PTC material encapsulating a pair of bus wires, and a conductive layer disposed on an outer surface of the heater core such that the conductive layer levels the voltage generated at the outer surface of the heater core when an electric current is passed through the bus wires. The conductive layer draws the current evenly through lobes of PTC material encapsulating the bus wires. The conductive layer may be a coating, such as a conductive ink or paint, or may be an extruded or wrapped material applied to the heater core. Standard heater cable layers are applied over the conductive layer, including an electrically insulating layer that contacts a portion of the conductive layer and also may be separated, at points, from the conductive layer by one or more air gaps.

Voltage-leveling monolithic self-regulating heater cable

Growing community of inventors

San Jose, CA, United States of America

Mohammad Kazemi