Abstract: A high-intensity ionizer assembly having a Rogowski-shaped outlet. The ionizer assembly is adapted to be used with particle collection systems for pre-charging particulate matter entrained in a gas stream.

Abstract: A thyristor power controller for rapidly varying the current delivered to a load and including: a clock circuit for developing a clock pulse for each zero crossing of an AC source, an analog phase circuit responsive to an adjustment current and operative to produce a firing signal for each clock pulse, a first thyristor acting on a positive half cycle of an AC source, a second thyristor acting on a negative half cycle of an AC source, a first thyristor control circuit enabling and disabling the first thyristor, a second thyristor control circuit enabling and disabling the second thyristor, and a thyristor selector operative to route the firing signal to the first or second control circuit.

Abstract: An impact device (15) applies hammer-like blows, or impact forces, to a metallic support frame (13) from which high-voltage electrodes (10) are suspended in an electrostatic precipitator in order to dislodge accumulated particulates from high-voltage electrodes (10). The impact device (15) is electrically isolated by an insulator (19) from metallic components of the precipitator other than the support frame (13) and components electrically connected to the support frame (13). The insulator (19) has a bore (18) that accommodates movement of the impact device (15) from a withdrawn position away from the support frame (13) to an impact position in contact with the support frame (13) upon energization and de-energization of a solenoid (17). The insulator (19) remains unstressed as the impact device (15) contacts the support frame (13).

Abstract: A device for detecting a persisting electrical overload in an electrical system includes means for monitoring an electrical parameter in the electrical system and for generating an electrical signal whose magnitude represents the instantaneous absolute value of the parameter, reference means which generates an output signal of predetermined value and which develops, in cooperation with the monitoring means, an electrical signal whose magnitude represents the amount by which the magnitude of the absolute value signal exceeds the predetermined value, integrator means to integrate the aforementioned electrical signal and to generate an output whose magnitude includes a component representative of the product of the electrical signal and a time-increasing value that represents the duration that an overload has persisted; and comparator means to continuously compare the magnitude of the integrator output signal with a second preselected value and which generates an indicative output whenever the integrator output

Abstract: Electrically-activated shaking devices are arranged in modules to shake the electrodes of an electrostatic precipitator, each module corresponding to a different section of the precipitator. An operating system for the shaking devices includes a main distributor circuit that sends electrical signals to individual control circuits at each of the modules in sequence and at a relatively fast rate. Each control circuit has an adjustable timer that independently generates pulses at a relatively slow rate and a synchronizing circuit that generates an output signal only if it receives a signal from the timer followed by a signal from the main distributor. Each control circuit further includes a secondary distributor circuit that operates in response to the synchronizing circuit to activate the shaking devices in the associated module sequentially. An inhibit device operated by the synchronizing circuit prevents more than a single shaker from being activated at a time.

Abstract: In an electrostatic precipitator, a downwardly directed corona discharge is produced at the entrance to dust collecting hoppers attached at the bottom of the precipitator chamber, the corona discharge being produced by an array of corona discharge points connected to a high voltage source and a grounded electrode grid positioned below the corona points near the hopper entrance either in the hopper or in the chamber.