Abstract: A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet that translates therein is provided. The drive circuit includes a supply bus, a return bus, a flyback circuit, and a switch. The supply bus is configured to couple the solenoid coil to a power supply and supply a coil current. The return bus is configured to provide a ground path for the coil current. The flyback circuit is coupled in parallel to only the solenoid coil. The flyback circuit includes only a bipolar diode. The switch is coupled in series with the solenoid coil and configured to couple and decouple the solenoid coil to the return bus.

Abstract: A method of controlling a solenoid valve having a solenoid coil and a poppet includes energizing a first node to a first voltage, and coupling the first node to the solenoid coil and energizing the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil to below an opening threshold. The method further includes energizing a second node to a second voltage with energy stored in the solenoid coil, and coupling the second node to the solenoid coil and energizing the solenoid coil using a DC signal configured to increase the current to above the opening threshold. The method further includes coupling the first node to the solenoid coil and energizing the solenoid coil using the PWM signal having a frequency and duty cycle configured to regulate the current to above a closing threshold.

Abstract: A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet that translates therein is provided. The drive circuit includes a supply bus, a return bus, a flyback circuit, and a switch. The supply bus is configured to couple the solenoid coil to a power supply and supply a coil current. The return bus is configured to provide a ground path for the coil current. The flyback circuit is coupled in parallel to only the solenoid coil. The flyback circuit includes only a bipolar diode. The switch is coupled in series with the solenoid coil and configured to couple and decouple the solenoid coil to the return bus.

Abstract: A method for handling a fluid includes separating the fluid into a liquid and a vapor within a container such that at least a portion of the vapor is disposed above the liquid, detecting a level of the liquid in the container, and actuating at least one valve to exhaust the vapor from the container to maintain the level of the liquid at or above a desired level. The at least one valve is communicatively coupled to a controller. The method further includes sending a signal from the at least one valve to the controller, and determining diagnostic data based at least in part on the signal.

Abstract: Systems and methods for suppressing vaporization of a volatile fluid dispensed from a pressure vessel are provided. The system includes an evaporator coupled in thermal communication with a first flow of volatile fluid from the vessel and in fluid communication with a second flow of volatile fluid from the vessel. The evaporator includes at least one channel for channeling the second flow of volatile fluid therethrough. A metering valve is coupled in fluid communication with the channel and between the evaporator and the vessel. In addition, the system includes a compressor coupled in fluid communication with and downstream from the at least one channel. Moreover, the system includes a return line coupled in fluid communication with an outlet of the compressor. The compressor is configured to compress the second flow of volatile fluid and channel the compressed second flow of volatile fluid to the pressure vessel via the return line.

Abstract: A system for handling a fluid includes a container for separating the fluid into a liquid and a vapor such that at least a portion of the vapor is disposed above the liquid. The system also includes at least one valve for releasing the vapor from the container, at least one sensor to detect a level of the liquid in the container, and a controller in communicatively coupled to the at least one valve and the at least one sensor. The controller is configured to control the at least one valve to release the vapor such that the liquid level is maintained at or above a desired liquid level. The controller is configured to determine diagnostic data based at least in part on signals received from the least one valve and the at least one sensor.

Abstract: A drive circuit for operating a solenoid includes a main switch and a charge pump circuit. The main switch is coupled in series with a coil of the solenoid. The main switch is configured to selectively enable current flow from a voltage source according to a main switching signal to translate a poppet of the solenoid between an opened position and a closed position. The charge pump circuit is coupled to the voltage source. The charge pump circuit is configured to discharge through the coil to translate the poppet from the closed position to the opened position, and to charge when the poppet is held in the opened position.

Abstract: A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet that translates therein is provided. The drive circuit includes a supply bus, a return bus, a flyback circuit, and a switch. The supply bus is configured to couple the solenoid coil to a power supply and supply a coil current. The return bus is configured to provide a ground path for the coil current. The flyback circuit is coupled in parallel to only the solenoid coil. The flyback circuit includes only a bipolar diode. The switch is coupled in series with the solenoid coil and configured to couple and decouple the solenoid coil to the return bus.

Abstract: Systems and methods for suppressing vaporization of a volatile fluid dispensed from a pressure vessel are provided. The system includes an evaporator coupled in thermal communication with a first flow of volatile fluid from the vessel and in fluid communication with a second flow of volatile fluid from the vessel. The evaporator includes at least one channel for channeling the second flow of volatile fluid therethrough. A metering valve is coupled in fluid communication with the channel and between the evaporator and the vessel. In addition, the system includes a compressor coupled in fluid communication with and downstream from the at least one channel. Moreover, the system includes a return line coupled in fluid communication with an outlet of the compressor. The compressor is configured to compress the second flow of volatile fluid and channel the compressed second flow of volatile fluid to the pressure vessel via the return line.

Abstract: A method of dispensing fluid from an apparatus includes determining a phase offset to separate actuation of a plurality of valve sub-sets into phases and determining a sub-phase offset to separate actuation of valves within each of the plurality of valve sub-sets. The method also includes sequentially actuating valves in a first sub-set based on the sub-phase offset, and sequentially actuating valves in a second sub-set based on the phase offset and the sub-phase offset such that (i) at least one valve in the second sub-set is actuated out of phase from a preceding valve in the first sub-set by the phase offset; and (ii) the at least one valve in the second sub-set is actuated out of phase from a preceding valve in the second sub-set by the sub-phase offset.

Abstract: A method of controlling a solenoid valve having a solenoid coil and a poppet includes energizing a first node to a first voltage, and coupling the first node to the solenoid coil and energizing the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil to below an opening threshold. The method further includes energizing a second node to a second voltage with energy stored in the solenoid coil, and coupling the second node to the solenoid coil and energizing the solenoid coil using a DC signal configured to increase the current to above the opening threshold. The method further includes coupling the first node to the solenoid coil and energizing the solenoid coil using the PWM signal having a frequency and duty cycle configured to regulate the current to above a closing threshold.

Abstract: Systems and methods for suppressing vaporization of a volatile fluid dispensed from a pressure vessel are provided. The system includes an evaporator coupled in thermal communication with a first flow of volatile fluid from the pressure vessel and in fluid communication with a second flow of volatile fluid from the pressure vessel. The evaporator includes at least one channel therein for channeling the second flow of volatile fluid therethrough. In addition, the system includes a compressor coupled in fluid communication with and downstream from the at least one channel. Moreover, the system includes a return line coupled in fluid communication with an outlet of the compressor. The compressor is configured to compress the second flow of volatile fluid and channel the compressed second flow of volatile fluid to the pressure vessel via the return line.

Abstract: A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet that translates therein is provided. The drive circuit includes a first node, a second node, a control circuit, and a flyback circuit. The first node is configured to be energized by a power source to a first voltage. The control circuit is coupled to the first and second nodes, and is configured to: (1) selectively couple the first and second nodes in series with the solenoid coil, and periodically energize the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil. The flyback circuit is coupled to the solenoid coil and configured to energize the second node to a second voltage with energy stored in the solenoid coil.

Abstract: Electric fluid flow monitoring apparatus, and agricultural fluid application systems and methods including the same are described. The fluid flow monitoring apparatus generally includes a housing, a sensor assembly, and a traveler. The housing defines an interior cavity, and includes an inlet for fluid to enter the interior cavity and an outlet for fluid to exit the interior cavity. The sensor assembly is disposed in the interior cavity, and extends longitudinally in the direction of fluid flow. The traveler is movably supported by the sensor assembly such that fluid flow through the interior cavity causes the traveler to move longitudinally along the sensor assembly. The sensor assembly detects a longitudinal position of the traveler relative to the sensor assembly.

Abstract: A system for handling a fluid includes a container for separating the fluid into a liquid and a vapor such that at least a portion of the vapor is disposed above the liquid. The system also includes at least one valve for releasing the vapor from the container, at least one sensor to detect a level of the liquid in the container, and a controller in communicatively coupled to the at least one valve and the at least one sensor. The controller is configured to control the at least one valve to release the vapor such that the liquid level is maintained at or above a desired liquid level. The controller is configured to determine diagnostic data based at least in part on signals received from the least one valve and the at least one sensor.

Abstract: A system for dispensing a fluid includes a container including a sidewall defining an interior space for holding the fluid and configured to separate the fluid into a liquid and a vapor. The system also includes at least one fluid inlet disposed in the sidewall, at least one liquid outlet disposed in the sidewall, a first sensor, a second sensor, and a controller. The first sensor is positioned adjacent to or upstream of the at least one fluid inlet and configured to detect a first temperature of the fluid. The second sensor is positioned adjacent to or downstream of the at least one liquid outlet and configured to detect a second temperature of the fluid. The controller is configured to determine a fluid temperature differential based on the first and second temperatures and determine an operational status of the system based on the fluid temperature differential.

Abstract: A drive circuit is provided for controlling a solenoid valve having a solenoid coil. The drive circuit includes a first semiconductor device, a flyback circuit, and a processor. The first semiconductor is coupled in series with the coil and is controlled by a gate signal to energize the coil. The flyback circuit is in parallel with the coil and includes a series-coupled second semiconductor device and a diode. The second semiconductor is controlled by a flyback control signal to enable the flyback circuit when the first semiconductor is controlled by the gate signal to hold the valve open. The diode has a low forward voltage to slow decay of a current conducted through the coil. The processor generates the gate signal to control the first semiconductor and to reduce a duty cycle of the gate signal when the flyback circuit is enabled to reduce power consumption by the coil.

Abstract: A drive circuit for operating a solenoid includes a main switch and a charge pump circuit. The main switch is coupled in series with a coil of the solenoid. The main switch is configured to selectively enable current flow from a voltage source according to a main switching signal to translate a poppet of the solenoid between an opened position and a closed position. The charge pump circuit is coupled to the voltage source. The charge pump circuit is configured to discharge through the coil to translate the poppet from the closed position to the opened position, and to charge when the poppet is held in the opened position.

Abstract: A method of dispensing fluid from an apparatus includes determining a phase offset to separate actuation of a plurality of valve sub-sets into phases and determining a sub-phase offset to separate actuation of valves within each of the plurality of valve sub-sets. The method also includes sequentially actuating valves in a first sub-set based on the sub-phase offset, and sequentially actuating valves in a second sub-set based on the phase offset and the sub-phase offset such that (i) at least one valve in the second sub-set is actuated out of phase from a preceding valve in the first sub-set by the phase offset; and (ii) the at least one valve in the second sub-set is actuated out of phase from a preceding valve in the second sub-set by the sub-phase offset.

Abstract: A drive circuit for controlling a solenoid valve having a solenoid coil and a poppet that translates therein is provided. The drive circuit includes a first node, a second node, a control circuit, and a flyback circuit. The first node is configured to be energized by a power source to a first voltage. The control circuit is coupled to the first and second nodes, and is configured to: (1) selectively couple the first and second nodes in series with the solenoid coil, and periodically energize the solenoid coil using a pulse-width-modulated (PWM) signal having a frequency and a duty cycle configured to regulate a current conducted through the solenoid coil. The flyback circuit is coupled to the solenoid coil and configured to energize the second node to a second voltage with energy stored in the solenoid coil.