Abstract: A modular power supply system (10) is provided for providing a multiplicity of output voltages from a plurality of respective converter modules (70a-70n). Each of the converter modules (70a-70n) has an input coupled to a DC high voltage bus (22) from which a respective output voltage is generated. The voltage supplied on DC bus (22) is generated by a power factor corrected boost converter circuit (20) which is coupled to an AC input source (12). Further, a battery backup module (40) is coupled to the high voltage DC bus (22) for supplying backup power whenever the bus voltage drops below a predetermined level.

Abstract: A universal electronic ballast system (10) is provided for actuating at least one gas discharge lamp (1900) having any one of a plurality of predetermined wattage ratings. Electronic ballast system (10) includes a filter circuit coupled to an AC power mains (100, 110) for substantially suppressing spurious signals passing into or from the power source. The filter circuit is coupled to a regulated switching power supply circuit (14) which generates a regulated boost voltage and draws a substantially constant in phase sinusoidal load current from the power source supplied to a switching circuit (16) which generates a regulated pulsating current at a predetermined frequency. Responsive to the regulated pulsating current a high voltage is induced in the primary windings (1710 and 1680) of induction transformer (T3). The high voltage is coupled to gas discharge lamp (1900) by means of the magnetic coupling betwen primary winding (1730) and secondary winding (1765) of the output transformer (T2).

Abstract: An improved self-regulating, no load protected electronic ballast system (10) is coupled to a power source (12) for actuating at least one gas discharge tube (b 66) with a regulated current and limited voltage to maintain the gas discharge tube (66) input and output power at a predetermined value. The improved ballast system (10) includes a filter circuit (11) coupled through a rectification circuit (16) to the power source (12) to provide a filtered output (28). The output line (28) is coupled to a first toroidal transformer winding (58) of self-regulating circuit (17) for monitoring the regulated current coupled to induction circuit (15). The induction circuit (15) includes a primary winding (42) tapped to provide an autotransformer configuration for establishing the magnitude of the regulated current.

Abstract: Apparatus for providing density compensation to measured volumes of fluid flow wherein means for sensing the fluid parameter having a dominant effect on the density thereof are adapted to produce an output signal which varies as a function of the magnitude of the sensed parameter. This output signal is supplied to a voltage-frequency converter which produces output pulses continually at a frequency corresponding to the magnitude of the output signal. The converter is gated to a coincidence gate for a period of predetermined duration upon detection of each unit change of volumetric fluid flow with the number of pulses accepted by the gate during such period reflecting the value of the dominant parameter and, hence density of the fluid. A frequency divider is configured to divide the gate output by a predetermined factor with each output pulse or count issued by the frequency divider representing a density corrected unit change of volumetric fluid flow.

Abstract: A mass flow meter including a fluid volume indicating means for measuring the volume of a fluid, a temperature sensor for indicating the temperature of the fluid being measured by the fluid volume indicating means, a density compensator connected to the volume indicating means and the temperature means to provide an indication of mass flow rate of the fluid material, and counting means to accurately accumulate the indication of mass units to provide the total mass of the fluid being measured. The signal output of the volume indicating means and the temperature sensor from the temperature sensor provide input pulses to the variable pulse width means in the density compensator to initiate an output measuring envelope pulse and to cut off the output measuring envelope pulse. The envelope pulse is an input density compensated envelope pulse to the counting means. The density compensator includes an oscillator producing a high frequency output to the counter means.