Abstract

A solenoid coil discharging circuit includes a rectifier, transistor, and diode. The rectifier is coupled to an alternating current signal, and provides a rectified signal in response to being coupled to the alternating current signal. The transistor is coupled to the rectifier circuit, and biased in on in response to the alternating current signal being coupled to the rectifier, thereby enabling coupling of the rectified signal to a solenoid coil. The diode is coupled to the rectifier, and discharges current from the solenoid coil in response to the alternating current signal being de-coupled from the rectifier. A method of discharging a solenoid coil includes rectifying an alternating current signal to provide a rectified signal, biasing a transistor on in response to the alternating current signal being rectified, thereby enabling coupling of the rectified signal to the solenoid coil through the transistor, and discharging current from the solenoid coil through the diode in response to discontinuing rectification of the alternating current signal.

IPC Classes  ?

• H01F 7/06 - ElectromagnetsActuators including electromagnets
• H01H 47/04 - Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current for modifying the operation of the relay for holding armature in attracted position, e.g. when initial energising circuit is interrupted or with reduced energising current
• H01H 47/32 - Energising current supplied by semiconductor device
• H02H 9/04 - Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
• H01F 7/10 - ElectromagnetsActuators including electromagnets with armatures specially adapted for AC

Abstract

A DC solenoid coil current controller includes a rectifier, pulse width modulator, and power driver. The rectifier inputs an alternating current signal and a direct current signal, and outputs a rectified signal using at least one of the alternating current signal and the direct current signal. The pulse width modulator outputs a pulse width modulated signal in response to the rectified signal. The power driver controls a DC solenoid coil using the pulse width modulated signal, thereby enabling a direct current DC solenoid coil to be controlled in response to the alternating current signal. A method of controlling current to a DC solenoid coil is also disclosed.

IPC Classes  ?

• H01H 9/00 - Details of switching devices, not covered by groups
• H01H 47/32 - Energising current supplied by semiconductor device
• H01H 47/00 - Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
• H02H 3/087 - Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition, with or without subsequent reconnection responsive to excess current for DC applications
• F02D 41/20 - Output circuits, e.g. for controlling currents in command coils

Abstract

According to aspects described herein, there is disclosed a method of and system for indicating a fault associated with a fluid valve moveable between an open and a closed operative position. The method and system compare a valve state indicator to a valve last command, wherein the valve state indicator represents a detected operative position of the valve and the valve last command being an operative command sent to the fluid valve. The method and system also initiate a fault indication after a predetermined time delay relative to the valve last command being sent and when the valve state indicator does not match the valve last command. After the time delay a fault indication can be initiated immediately upon receipt of a different valve state indicator.

IPC Classes  ?

• F16K 37/00 - Special means in or on valves or other cut-off apparatus for indicating or recording operation thereof, or for enabling an alarm to be given