Relay with core conductor and current sensing
AssigneeInternational Controls and Measurements Corporation
InventorHassan Kadah
Life of this patent
Estimating the term…
Abstract
A relay situated in series between an AC line source and an AC load has a core conductor connected with the fixed N.O. contact, so that load current flows axially through the core of the actuator coil. Alternatively, the fixed N.C. contact may be connected with the core conductor. A plate armature with leaf springs can achieve linear axial action. A sensor connected to leads of a winding of the actuator coil picks up a an induced voltage that is representative of the current supplied to the load. This provides a simple arrangement for monitoring for current level and can be used for measuring power factor or A(D at the load device. In a three phase embodiment, phase imbalance can be detected.
Claims20
An electromechanical relay adapted to be situated in series with a source of AC power and an AC load, the relay comprising an actuator coil to which an actuator current is controllably applied for closing and releasing a contactor armature of the relay, the contactor armature including means normally biasing the contactor armature away from the actuator coil and a first electrical contact carried on said contactor member;
- a second electrical contact adapted to make contact with said first contact when the actuator coil closes said contactor armature, the second contact being connected to a core conductor that passes through an axial bore of said actuator coil, the core conductor carrying load current to said AC load when said actuator coil closes said contactor armature;
- and a load current sensor having input terminals connected to a winding of said actuator coil for picking up an induced voltage representative of the load current carried on said core conductor.
An electromechanical relay adapted to be situated in series with a source of AC power and an AC load, the relay comprising an actuator coil to which an actuator current is controllably applied for closing and releasing a contactor member of the relay, the contactor member including means normally biasing the contactor member away from the actuator coil and a first electrical contact carried on said contactor member;
- a second electrical contact adapted to make contact with said first contact when said contactor member is released but to break contact when the actuator coil closes said contactor member, the second contact being connected to a core conductor that passes through an axial bore of said actuator coil, the core conductor carrying load current to said AC load when said actuator coil releases said contactor member;
- and a load current sensor having input terminals connected to a winding of said actuator coil for picking up an induced voltage representative of the load current carried on said core conductor.
An electromechanical relay adapted to be situated in series with a source of polyphase AC power and an AC load, the relay comprising an actuator coil to which an actuator current is controllably applied for closing and releasing a contactor member of the relay, the contactor member including means normally biasing the contactor member away from the actuator coil and a plurality of first electrical contacts carried on said contactor member, each said first contact being coupled to a respective phase conductor of said source;
- a respective plurality of second electrical contacts adapted to make contact with said first contacts when the actuator coil moves said contactor member to one of a closed position and a released position, the second contacts being connected to respective core conductors that pass through an axial bore of said actuator coil, the core conductors carrying the respective phase portions of the load current to said AC load when said actuator coil moves said contactor member to said one of its open and closed positions;
- and a load current sensor having input terminals connected to a winding of said actuator coil for picking up an induced voltage representative of the net of the respective phases of said load current carried on said core conductors.
An electromechanical relay adapted to be situated in series with a source of electrical power and a load, the relay comprising an actuator coil to which actuator current is controllably applied for closing and releasing a contactor member of the relay, the contactor member including spring members normally biasing the contactor member away from the actuator coil in a linear direction along an axis of the actuator coil;
- a first electrical contact carried on said contactor member;
- a second electrical contact adapted to make contact with the first contact when the actuator coil draws in said contactor member;
- the second contact being connected to a core conductor that passes through an axial bore of said actuator coil, the core conductor carrying load current to said load when said actuator coil draws in said contactor member;
- and a load current sensor having input terminals connected to a winding of said actuator coil for picking up an induced voltage representative of the load current being carried on said core conductor.
An electromechanical relay adapted to be situated in series with a source of electrical power and a load, the relay comprising an actuator coil to which actuator current is controllably applied for closing and releasing a contactor member of the relay, the contactor member including spring members normally biasing the contactor member away from the actuator coil in a linear direction along an axis of the actuator coil;
- a first moving electrical contact carried on said contactor member and positioned along the axis of said actuator coil;
- and a second fixed electrical contact held at a fixed position relative to said actuator coil along said axis;
- such that said first and second contacts are urged into one of an open and closed condition when said actuator current is applied to the actuator coil, and are urged into the other of said open and closed conditions when said actuator current is removed from said actuator coil.
Dependencies are inferred from the claim text.