Abstract: A device for detecting a fault in an AC supply comprises a circuit (CT, 100) for detecting a fault in an AC supply to a load (LD) and providing a corresponding output (IO), and an electromechanical switch means (SOL1, SWI) to disconnect the load from the supply if said output persists for at least a certain period of time. The device includes a generator (30) of intermittent test pulses each simulating a fault. In certain embodiments the duration of each test pulse is less than said certain period of time, and the circuit includes means (D2) for providing a visual and/or audible indication in response to the detection of test pulses by the detecting circuit.

Abstract: An apparatus for testing an arc fault detector comprises a housing (30) having an ac power input plug (32) and an ac power output socket (34), the plug being connected to supply ac power to the socket via electrical supply conductors (L, N) inside the housing. The socket (34) allows connection of an external appliance (36) to the housing for receiving power from the plug (32) through the internal supply conductors. An arc generator (100) inside the housing is connected between the plug (32) and the socket (34). The arc generator comprises at least one pair of contacts and means to vibrate the contacts alternately open and closed.

Abstract: A fluid flow control device controls flow of fluid in a capillary pathway device having a first capillary passage with an inlet and an outlet and a fluid application region for receiving a liquid sample for entry to the capillary passage via the inlet, with the fluid flow control device comprising first sealing means operable for releasably sealing the outlet of the first capillary passage.

Abstract: A sample metering device for a liquid sample comprises at least one capillary passage with an inlet and an outlet; a side passage extending from the capillary passage part way along the length thereof and leading to an outlet; a fluid application region for receiving a liquid sample to be tested, for entry to the capillary passage via the inlet; first sealing means operable releasably to seal the outlet of the capillary passage; and second sealing means operable releasably to seal the outlet of the side passage.

Abstract: A system and method for providing updates to medical devices is disclosed. In one example, the medical devices are configured to pull update files in response to the reception of an update message from a server. Once the update files are downloaded by a medical device, the update files can be installed. While the medical device pulls the update files, the medical device can continue with its normal operation. If desired, a user can select which medical devices should be updated, based on any desired factors, such as the physical location of the device, the model of the device, the type of device, and the way the device is being used.

Abstract: Paunch-sludge from an abattoir is mixed with the fatty DAF-float from an abattoir, and placed in a shearing vessel. The mixture of the two material thickens the medium in which the matted strands are contained, enabling shearing to be more effective; so much so that paunch-sludge can now be sheared to a homogeneous liquid. The technique can be used with other sludges and other fatty waste materials.

Abstract: An apparatus for detecting a leakage current flowing between at least one supply conductor of a multi-conductor electricity supply to load and non load currents carrying electrical conductor nominally insulated from the supply conductor. The apparatus includes a current transformer having a primary winding and a secondary winding. The primary winding is connected between the non load current carrying conductor and at least one other supply conductor so that leakage current flowing between the at least one supply conductor and the non load current carrying conductor flows through the primary winding to the other supply conductor. An electromechanical relay has a set of normally-closed contacts in series with the electricity supply. Circuitry connecting the secondary winding of the current transformer and the relay is provided so the relay is actuated by a current induced in the secondary winding by a leakage current meeting certain criteria as to magnitude and/or duration.

Abstract: An arc fault detector comprises a current transformer (CT) having a primary winding and a secondary winding (W1), the primary winding being formed by at least one conductor (L) of an AC or DC supply circuit. The inductance of the CT is selected so that the CT has a lower frequency operating point (LFOP) of at least 10 KHz. The detector also comprises circuitry (10, 12, SW) for disconnecting the supply if the voltage induced in the secondary winding meets predetermined criteria as to magnitude and duration.

Abstract: A device for detecting a fault in an AC supply comprises a circuit (CT, 100) for detecting a particular type of fault in an AC supply to a load (LD) and providing a corresponding output (10). A relay (RLA) is responsive to said output (10) to open a set of load contacts (SW1) in the AC supply to disconnect the load from the supply. Test means (TS, Rt, W2) are provided for simulating a supply fault of the said type, and means (C3, R5, SCR2, SOL, SW2) are provided for causing the load contacts (SW1) to open if they do not open in response to the simulated fault within a certain period of time.

Abstract: The present invention relates to waste screening apparatus and methods, particularly but not exclusively for screening waste material streams for recycling and the like. It also relates to an apparatus for separating portions or fractions of a waste material stream, generally to facilitate recycling of one or more of said fractions, and a method therefor; and to combinations of same.

Abstract: Disclosed is an adjustable light fixture. The light fixture can include a housing assembly comprising an outer housing surrounding a central opening; a first adjustment mechanism configured to tilt the light source comprising a first rotating member; and a second adjustment mechanism configured to rotate the light source comprising a second rotating member, where the first and second rotating members are substantially parallel to one another. The light fixture can also include a biasing member that will return the housing assembly to a first tilted position from a second titled position.

Abstract: A residual current device for an AC electricity supply comprises a housing (10) and a first load conductor (L) inside the housing connected in series between the supply and a load and including a set of contacts (18) by which an electrical connection between the supply and the load may be made or broken. A current transformer is disposed inside the housing and has a toroidal core (TI) the first load conductor passing through the core and forming one primary winding of the current transformer. At least one further load conductor (N) outside the housing passes through the core (T) via an opening (32) in the housing and forms a further primary winding of the current transformer. A secondary winding (W) on the core produces an output in response to a residual current, and a circuit (RCC) inside the housing is responsive to the output on the secondary winding to open the contacts if the residual current is above a predetermined level.

Abstract: A switching circuit, e.g. an RCD, comprises a pair of mechanical contacts (M) in an alternating current electricity supply (N, L) and circuit means (SCR) for opening the contacts to cut off the supply in response to a switching signal (S). The switching circuit includes further circuit means (Rs, Cs, D2, D3, Q1, Q2) for defining successive periods of time (“activation windows”) during which the magnitude of the supply voltage is not at a maximum and allowing the contacts to open in response to a switching signal only during such windows.

Abstract: Sewage sludge that has been de-watered to 25% solids is subjected to a combination of shearing and heating that liquefies the sludge, and drops its viscosity to below 12,000 cP. The fact of liquefaction prepares the sludge such that subsequent drying can be done more cost-effectively than hitherto. After drying, the dried sludge can be incinerated.

Abstract: A residual current device comprises a circuit (CT, 10, 12) for detecting a current imbalance in an AC supply to a load indicative of a residual current and providing a corresponding output. A relay RLA has contacts SW1 in the AC supply to the load. The relay contacts SW1 automatically close when a closing current is passed through the relay and is thereafter maintained closed so long as a holding current, less than the closing current, passes through the relay. A capacitor C1 is connected to the AC supply in parallel with the relay RLA such that, upon application of power from the AC supply, current flows to the charge storage device. An electronic switch SCR2 in series with the relay is turned on when the voltage on the capacitor exceeds the breakover voltage of a Zener diode ZD2 to allow discharge of the capacitor through the relay to provide a current exceeding the closing current, the AC supply thereafter providing a holding current for the relay at least when the supply is at a certain minimum voltage.

Abstract: Already-treated sludge is fed back into incoming sewage, and is effective to supply nutrients needed for the microbiological breakdown of the sludge. The feedback sludge has a solids content of 10% or more, and has been sheared and heated to drive its viscosity down to 10,000 cP or less. In sludge done that way, nutrients are preserved and presented to the sewage to be treated in highly liquidized and solubilized form, whereby the nutrients are very bio-available to the microbes in the sewage. Large improvements in the elimination of biomass can result.

Abstract: A residual current device for an AC electricity supply comprises a housing (10) and a first load conductor (L) inside the housing connected in series between the supply and a load and including a set of contacts (18) by which an electrical connection between the supply and the load may be made or broken. A current transformer is disposed inside the housing and has a toroidal core (TI) the first load conductor passing through the core and forming one primary winding of the current transformer. At least one further load conductor (N) outside the housing passes through the core (T) via an opening (32) in the housing and forms a further primary winding of the current transformer. A secondary winding (W) on the core produces an output in response to a residual current, and a circuit (RCC) inside the housing is responsive to the output on the secondary winding to open the contacts if the residual current is above a predetermined level.

Abstract: Already-treated sludge is fed back into incoming sewage, and is effective to supply nutrients needed for the microbiological breakdown of the sludge. The feedback sludge has a solids content of 10% or more, and has been sheared and heated to drive its viscosity down to 10,000 cP or less. In sludge done that way, nutrients are preserved and presented to the sewage to be treated in highly liquidised and solubilised form, whereby the nutrients are very bio-available to the microbes in the sewage. Large improvements in the elimination of biomass can result.

Abstract: A residual current device comprises a circuit (CT, 10, 12) for detecting a current imbalance in an AC supply to a load indicative of a residual current and providing a corresponding output. A relay RLA has contacts SW1 in the AC supply to the load. The relay contacts SW1 automatically close when a closing current is passed through the relay and is thereafter maintained closed so long as a holding current, less than the closing current, passes through the relay. A capacitor C1 is connected to the AC supply in parallel with the relay RLA such that, upon application of power from the AC supply, current flows to the charge storage device. An electronic switch SCR2 in series with the relay is turned on when the voltage on the capacitor exceeds the breakover voltage of a Zener diode ZD2 to allow discharge of the capacitor through the relay to provide a current exceeding the closing current, the AC supply thereafter providing a holding current for the relay at least when the supply is at a certain minimum voltage.