Abstract: A device and method that determine a freewheeling rotation of an electric motor. The method includes steps of measuring first and second signals from respective first and second windings of an unenergized motor, and determining from the first and second signals whether the unenergized motor is rotating. The method may also include determining from the first and second signals the direction of rotation if the unenergized motor is rotating. The method may further include measuring a third signal from a third winding of the unenergized motor, and determining whether the motor is rotating may include determining that the motor is not rotating if the first, second, and third signals are equal. The first and second signals may each comprise a respective back voltage.

Abstract: A four port reversing valve for a reversible-cycle refrigeration system having a compressor is constructed with the reversing valve having a first inlet port adapted to be connected to the compressor and second, third, and fourth ports. The four port reversing valve is further provided with a valve member operable between first and second positions. The valve member in its first position connects the first inlet port with the second port and the third port with the fourth port, and the valve member in its second position connects the first inlet port with the fourth port, and the second port with the third ports. The second and third ports and the third and fourth ports are arranged so that the angle between the ports is about 135°. In one embodiment the valve member rotates, and in another it translates linearly. Several means are disclosed for actuating the valve member.

Abstract: A battery charger for a lead acid battery having a power supply with an input connected to an AC signal and an output connected to the battery. The power supply provides a charge current to the battery. A clock connected to the AC signal provides clock pulses having transitions synchronized with zero crossings of the AC signal. A voltage monitor connected to the battery detects a battery voltage substantially simultaneously with a zero value of the charge current. A charge mode control is connected to the clock and the voltage monitor for commanding different battery charge currents. The voltage monitor includes a temperature compensation circuit. The battery charger includes a display module that can be placed at a location remote from the battery charger and convenient to the user.

Abstract: Aqueous emulsion polymer compositions stabilized with the reaction product of alkoxylated alcohols and an epihalohydrin or a trihaloalkanes.

Abstract: A power supply circuit detects ground fault paths, and miswiring of the load, using a test mode in which electrical power is applied to only one power output terminal of the power supply relative to the ground terminal, while substantially no electrical power is applied to the second power output terminal relative to the ground terminal. If application of power during the test mode causes substantial current flow through ground, then there is a ground fault path, or an incorrect connection between the midpoint of the load and ground. The power supply further includes unique features for signaling the presence and kind of fault it has detected; the power supply is capable of distinguishing between ground faults in at least two different locations, and when a fault is detected, the power supply signals the presence of the fault and its location, e.g., by timed blinking of the connected discharge light. These features are enhanced by a diagnostic analyzer for connection to the power supply.

Abstract: Aqueous emulsion polymer compositions stabilized with the reaction product of alkoxylated alcohols and an epihalohydrin or a trihaloalkanes.

Abstract: A four port reversing valve for a reversible-cycle refrigeration system having a compressor is constructed with the reversing valve having a first inlet port adapted to be connected to the compressor and second, third, and fourth ports. The four port reversing valve is further provided with a valve member operable between first and second positions. The valve member in its first position connects the first inlet port with the second port and the third port with the fourth port, and the valve member in its second position connects the first inlet port with the fourth port, and the second port with the third ports. The second and third ports and the third and fourth ports are arranged so that the angle between the ports is about 135°. In one embodiment the valve member rotates, and in another it translates linearly. Several means are disclosed for actuating the valve member.

Abstract: A four port reversing valve for a reversible-cycle refrigeration system having a compressor is constructed with the reversing valve having a first inlet port adapted to be connected to the compressor and second, third, and fourth ports. The four port reversing valve is further provided with a rotatable valve member operable between first and second positions. The valve member in its first position connects the first inlet port with the second port and the third port with the fourth port, and the valve member in its second position connects the first inlet port with the fourth port, and the second port with the third ports. The second and third ports and the third and fourth ports are arranged so that the angle between the ports is greater than about 90°. The third port is preferably oriented at an angle of about 120° with respect to the second and fourth ports, but the third port may also be oriented at an angle of about 135° with respect to the second and fourth ports.

Abstract: The invention is a surfactant composition comprising about 20 weight % to about 76 weight % of a fatty alcohol ethoxylate having a degree of ethoxylation of at least 14, about 4 weight % to about 40 weight % alkylpolyglycoside, and about 20 weight % to about 60 weight % water, wherein said composition is a liquid at room temperature, free of gel or solid phase, lattices containing said surfactant composition and a process for making said lattices.

Abstract: A power supply circuit detects ground fault paths, and miswiring of the load, using a test mode in which electrical power is applied to only one power output terminal of the power supply relative to the ground terminal, while substantially no electrical power is applied to the second power output terminal relative to the ground terminal. If application of power during the test mode causes substantial current flow through ground, then there is a ground fault path, or an incorrect connection between the midpoint of the load and ground. The power supply further includes unique features for signaling the presence and kind of fault it has detected; the power supply is capable of distinguishing between ground faults in at least two different locations, and when a fault is detected, the power supply signals the presence of the fault and its location, e.g., by timed blinking of the connected discharge light. These features are enhanced by a diagnostic analyzer for connection to the power supply.

Abstract: A power supply power supply circuit of the kind which includes a transformer having primary and secondary windings and an oscillator for driving the primary winding in a bi-directional fashion, suitable for driving gas discharge lighting such as neon signs, which prevents dangerous overvoltage output conditions and detects relatively low level ground fault currents. The transformer includes a clamp winding which is in proximity to and capacitively coupled to the secondary winding. The terminals of the clamp winding are connected to a current imbalance detection circuit for detecting imbalance between the current flowing into one clamp winding terminal and the current out of the other clamp winding terminal. In a ground fault condition, ground fault current flows in an unbalanced fashion into the clamp winding terminal(s), and through the capacitive coupling to the secondary winding.

Abstract: A transformer control circuit which includes a ground fault detection circuit that detects ground fault currents in the transformer secondary and delivers a ground fault detection signal to the primary circuit. This circuit derives power from the secondary winding and transmits the ground fault detection signal through an optical isolation barrier, thus avoiding the use of an auxiliary transformer. The ground fault detection circuit further includes safety features for detecting whether AC power is being supplied without earth ground being connected, and/or whether there is an undesired electrical connection between a transformer output connection and earth ground, which would defeat the ground fault detection circuit.