Isolator circuit
AssigneeTyco Fire & Security GmbH
InventorsFaruk Meah, Andrew D. Naish, Steven Ian Bennett
Life of this patent
Estimating the term…
Abstract
An isolator circuit (25) for a unit of a safety system (10) includes a power control line (14) connectable to a first loop of a safety system and a power connection (16) connectable to a second loop of the safety system. A switch (26) is connected to the power control line (14), and the switch has a closed configuration and an open configuration. A controller (28) controls the configuration of the switch (26). If a voltage across the circuit (10) from the power connection (16) to the power control line (14) falls below a predetermined level, the controller (28) opens the switch (26), thereby causing a disconnection to occur in the first loop.
Claims20
A unit of a safety system, comprising:
- an optical data receiver for receiving an optical data signal from an external source, and
- an isolator circuit;
- the isolator circuit comprising:
- a power control line;
- a first and a second power connection;
- a switch in the power control line, the switch having a closed configuration and an open configuration;
- and
- a controller for operating the switch;
- wherein the controller is arranged such that, when it receives an isolation signal in the optical data signal, the controller opens or closes the switch in response, thereby causing a disconnection to occur in the power control line;
- and
- wherein the switch is operable via the optical data receiver.
A unit of a safety system, comprising:
- an optical data receiver for receiving an optical data signal from an external source, and
- an isolator circuit, including:
- a power control line;
- a first and a second power connection;
- a switch in the power control line, the switch having a closed configuration and an open configuration;
- and
- a controller for operating the switch in response to an isolation signal, the controller controlling the switch to cause a disconnection to occur in the power control line, wherein the isolation signal is sent via an optical data transmitter of the external source to the optical data receiver and processed by the controller which, in response, opens the switch.
Dependencies are inferred from the claim text.