Power supplies


For the practical implementation of the above mentioned facts, the portable electronic digital coercive force meter with self-contained power supply, attached converter and closed type magnetic core. Instrument error is 5 %.  [c.29]

Temperatures operating range-Power supply -Overall dimensions -Mass -  [c.343]

Fig. 2 shows principal block diagrams of testing systems on the basis of GDC (where a - a block diagram with conductive coupling b - a block diagram with X-ray triggering, 1 - a master two-channel oscillator 2 - high voltage supply 9 - pulse generator for triggering of an X-ray radiator 4 - a pulse radiation source 5 - GDC 6 - pulse generator for GDC power supply 7 - TV camera tube 8 - computer 9 - X-ray radiation detector).  [c.540]

The maximum desilvering speed is related to the maximum current the power supply will deliver. When the efficiency is high, a current of lA will recover 4g of metallic silver per hour. The daily load determines the maximum current required. A 3A unit will typically be used for up to 15 m of film per day.  [c.605]

The first system was ordered in late March 1995, was available for field use on June 16, and was first used in actual waste sampling operations in early July 1995. The other three systems were delivered during November and December of 1995 and were all deployed by January 12, 1996. Approximately twenty ergonomic and electrical/mechanical changes were supplied with the latter three systems. These changes included a relocation of the display monitors, the S-VHS recorder, and the thermal image printer. The major mechanical changes included the addition of enclosed fork-lift pockets in the cabinet s frame, additional control cabinet ventilation, and a slight increase in the size of the lower control cabinet console which allowed for relocation of the 160 kV x-ray power supply and the refrigerated, x-ray tube cooling unit.  [c.610]

The EU contains capacitor battery (CB), current source (CS), accumulator (Ac), controlled by CS, impulse former (IF),power supply (PS), two comparators (Cpl,Cp2),  [c.649]

Fig. 1 shows the block diagram of the vibrometer, in which the most sensible to small phase variations interferometric scheme is employed. It consists of the microwave and the display units. The display unit consists of the power supply 1, controller 2 of the phase modulator 3, microprocessor unit 9 and low-frequency amplifier 10. The microwave unit contains the electromechanical phase modulator 3, a solid-state microwave oscillator 4, an attenuator 5, a bidirectional coupler 6, a horn antenna 7 and a microwave detector 11. The horn antenna is used for transmitting the microwave and receiving the reflected signal, which is mixed with the reference signal in the bidirectional coupler. In the reference channel the electromechanical phase modulator is used to provide automatic calibration of the instrument. To adjust the antenna beam to the object under test, the microwave unit is placed on the platform which can be shifted in vertical and horizontal planes.  [c.655]

In addition to the controlling computer the system contains only a small control unit - PSP-4 (weight approx. 5 kg.) which among other system components includes a motor control system integrated closely with the PS-4 ultrasonic system. For communication between the PSP-4 control unit and the robot as well as robot power supply is used a single cable less than 10 mm. in diameter.  [c.870]

The electronic block, which includes block of the analysis and registration and control system engines, and block of the source-receiver of acoustic oscillations are universal for any installations of this type. As the source-receiver of acoustic oscillations the ultrasonic flow detector is usually use. It s, as a rule, the serial devices for example y/f2-12. The electronic block contains the microprocessor device or PC, device of the power supply and management of engines  [c.883]

The Driving Module houses power supply, circuits for determination of travel distance (odometer wheels) and circumferential orientation, and a computer and a storage facility for all data recorded. The Driving Module has cups extending to the pipe wall, thus providing the movement of the tool after its launching into the continuous oil flow.  [c.1060]

When a battery (or a generator or other power supply) outside the system drives current, i.e. a flow of electric charge, tlirough a wire that passes tlirough the system, work is done on the system  [c.327]

A superconducting magnet consists of a cryostat, main coil, superconducting shim set and a means for attaching the current supply to the main coil (figure B1.12.4). The cryostat consists of two vessels for the liquid cryogens, an iimer one for helium and the outer one for nitrogen. Then, to insulate these, there are several vacuum jackets with a radiation shield. The aim is to reduce heat leakage to the iimer chamber to conserve helium. Superconducting magnets in NMR are usually operated in persistent mode, which means that, after a current is introduced, the start and end of the main coil are effectively connected so that the current has a continuous path within the superconductor and the power supply can then be discoimected. To achieve this the circuits within the cryostat have a superconducting switch. The coil circuits are also designed to cope with a sudden, irreversible loss of superconductivity, tenned a quench. There are resistors present (called dump resistors) to disperse the heating effect and prevent damage to the main coil when a quench occurs.  [c.1473]

The heat capacity of a gas at constant pressure is nonually detenuined in a flow calorimeter. The temperature rise is detenuined for a known power supplied to a gas flowing at a known rate. For gases at pressures greater than about 5 MPa Magee et al [13] have recently described a twin-bomb adiabatic calorimeter to measure Cy.  [c.1907]

Of recent interest is a crystalline tin-niobium alloy that is superconductive at very low temperatures. This promises to be important in the construction of superconductive magnets that generate enormous field strengths but use practically no power. Such magnets, made of tin-niobium wire, weigh but a few pounds and produce magnetic fields that, when started with a small battery, are comparable to that of a 100 ton electromagnet operated continuously with a large power supply.  [c.119]

These relationships can be used to estimate the amount of CPU time, disk space, or memory needed to run calculations. Let us take the example of a researcher, Jane Chemist, who would like to compute some property of a polymer. She first examines the literature to determine that an ah initio method with a moderately large basis set will give the desired accuracy of results. She then runs both single point and geometry optimization calculations on the monomer, which take 2 and 20 minutes, respectively. Since the calculation scales as N, a geometry optimization for the trimer, which has three times as many atoms, will take approximately 3" 20 minutes or about 27 hours. Jane would like to model up to a 15-unit chain, which would require 15" 20 minutes or about 2 years. Obviously, the use of ah initio methods for geometry optimization is not acceptable. Jane then wisely decides to stop at the 10-unit chain and use geometries optimized with molecular mechanics methods, which takes under an hour for the optimization. She then obtains the desired results with singlepoint ah initio calculations, which take 10" 2 minutes or 2 weeks for the largest molecule. This final calculation is still rather large, but it is feasible since Jane has her own work station with an uninterruptable power supply.  [c.129]

Calvanostats A galvanostat is used for dynamic methods, such as constant-current coulometry, in which it is necessary to control the current flowing through an electrochemical cell. A schematic diagram of a manual constant-current galvanostat is shown in Figure 11.3. If the resistance, R, of the galvanostat is significantly larger than the resistance of the electrochemical cell, and the applied voltage from the power supply is much greater than the cell potential, then the current between the auxiliary and working electrodes is equal to  [c.464]

The basic instrumentation for capillary electrophoresis is shown in Figure 12.41 and includes a power supply for applying the electric field, anode and cathode compartments containing reservoirs of the buffer solution, a sample vial containing the sample, the capillary tube, and a detector. Each part of the instrument receives further consideration in this section.  [c.601]

Power semiconductors Power supplies  [c.807]

Figure 8 shows the basic components of an electronic scale based on strain-gauge load ceUs. A power supply (not shown, but usually housed in the indicator) provides operating power for the indicator and the input voltage for the load ceU. The analogue signal produced by the load ceU is sensed by the analogue-to-digital (A/D) converter, which sends digital weight information to the digital computer. The digital computer comprises the microprocessor.  [c.326]

Terminal block Vor single point power supply with electric heat) DCE units  [c.361]

Discharge electrodes must be tensioned to hold the wire taut and maintain spacing. Tensioning may be accompHshed by attaching a weight (5—10 kg), held in a weight-spacing frame to reduce sway, to the bottom of each wire. In some European designs, now offered in the United States, the wires are stretched between light-weight high-tension pipe frames. The wires may be heavy barbed ribbons that are unlikely to fail from arcing, an important aspect since no provision is made for wire replacement in these rigid frames. The wire supporting frames are hung from high voltage insulators in suitable enclosures on top of the precipitator. Dust, fumes, and mist must be prevented from entering these insulator compartments and coating the insulators with a conductive film. The insulator compartments may be purged with clean air and heated to prevent condensation. In a mist precipitator, Hquid drains from the collecting surfaces, but a dry dust precipitator must be rapped at intervals using a weight, hammers, or vibrators. The dust, broken loose from the surface, sHdes down the plate into the dust hoppers. Dust is removed from the hoppers, usually batch-wise, with suitable conveyors. A precipitator s power supply is usually rectified ac.  [c.399]

Power Supply. The preferred power supply for a modem precipitator is a siUcon semiconductor power rectifier submerged in oil along a step-up transformer. Typical output voltages are 70—105 kV peak (45—67 root mean square average dc) negative polarity producing output of either two half-waves or one fiiU-wave. Lower voltages are used in some cases of smaller discharge electrode to collecting surface distances. Individual set capacities are typically 15—100 kVA, 250—1500 m A dc. Input power is usually 460 V 5%, single phase 60 Hz. Power supply capacity must be carefiiUy matched to the needs of the precipitator for maximal operation. The power supply is generally chosen to operate at 70% of capacity or higher. A greatly oversized power supply can result in poor electrical control, high peak currents or excessive sparking, frequent wire bum-out, and overall poor collection efficiency. Too small a power supply can result in its operation being controlled by current limitation and the inabiUty to reach optimum voltage for maximum collection efficiency. Gas temperature and composition, dust loading and resistivity, wire alignment, adequacy of rapping system to keep thin dust layers, collecting surface per electrical section, and geometric design are all factors that can affect power package sizing and selection (198).  [c.401]

All MWD tools have both a power supply and data transmission system often combined in one purpose built collar and usually located above the measurement sensors as shown in Figure 5.40 (a Teleco directional/gamma/resistivity tool). Data transmission may be within the downhole assembly from the sensors to a memory device or from the sensors to surface. The latter is usually achieved by mud pulse telemetry, a method by which data is transmitted from the tool in real time, i.e. as data is being acquired. Positive or negative pressure pulses created in the mudstream downhole travel through the mud (inside the drill pipe) to surface and are detected by a pressure transducer in the flowline. Positive pressure pulses are created by extending a plunger into a choke orifice, momentarily restricting flow (as shown in the top of Figure 5.40), an operation which is repeated to create a binary data string. Negative pulses are created by opening a bypass valve and venting mud to the annulus, momentarily reducing the drill pipe pressure.  [c.135]

Due to the high amount of data, which means a maximum data memory of 128 Mbyte per measuring in case of basic investigations, the first step of the data preprocessing was to extract the data sections concerning the origination of casting defects. The informations which are necessary to realize the extraction are contained in the synchronously recorded and already processed radioscopy image values. To eliminate occuring high respectively low frequence disturbances the extracted signal sections which are relevant for further analysis will be digital high respectively lowpass filtered (for example low frequence disturbances are caused by dispersion effects of the power supply, high frequence disturbances are caused by noise pulses from the thyristor control).  [c.15]

The physical integration thus consists in joining in one main circuit module the commutator, the feeding voltage shape converter, the noncontact ainplitude wide-range regulator of ac voltage, the parametric stabilizer, the power-line filter and the tube power supply circuit protector. The design integration consists in the main circuit performance unified module - the high-voltage transformer with magnetic control together with the high-voltage rectifier unit. The technological integration consists in the realization of multifunctionality of a unified high-voltage module of the apparatus main circuit.  [c.430]

For testing under field conditions a new mobile version of introscope has been developed, mounted on a lorry with high cross-country capability and self-contained power supply.  [c.452]

Owing to a finite storage time the operation of a radiation source and that of GDC should be synchronized, that is a power supply pulse is applied to GDC after a radiation pulse in a time interval, not exceeding the storage time. In the block diagram on the Fig. 2a this is realized through a direct conductive coupling between a radiation source and GDC and on the block diagram on the Fig.2b a fast detector of X-radiation is used (9). The first block diagram is the basis for production, as a rule, of portable testing systems with direct visualization of images from a GDC monitor screen. With the aim to minimize radiation dose, to optimize observation conditions and to provide necessary synchronization it is asually required to change the design of series pulse X-ray units to be used for these systems. The second version can be used in any pulse radiation sources without changing the design. They can be usually used in the mode of single-pulse registration of images by photo-recorders or by a TV system, combined with a computer (Fig2b 7,8). The testing system output data can help to decrease irradiation dose of tested objects.  [c.541]

The ethemet connection is combined with the power supply to the PSP-4 and the connected scanner into a single standard cable, that can be used for distances up to 100 m. By using special cables, the distance between the PSP-4 and the eontrol unit can be extended to practieally any distance.  [c.784]

The motors performing the scanner movements are selected from a range of motor modules. It runs from a small 2W DC-motor (Figure 2e) to a large 400W DC-motor. Some of the modules are available in water tight and radiation hardened versions. The standard motor module (Figure 2d) has a 70W DC-motor and driver and communication electronics is build into the module housing. A standard motor module connects directly to the Master Module or a Link Module (Figure 2b). The small motor modules, not containing driver electronics connect to the system through an external driver unit (Figure 2c). The large motor needs both external driver electronic and power supply.  [c.801]

Special electromagnetic shieldings, high quality pulsers and amplifiers, and special power-supplies provide excellent characteristics such as high dynamic range, high resolution and A-scans without PC-noise. Therefore, the PC boards are for some applications superior to standalone flaw detectors. The signal to noise ratio of up to 60 dB and the frequency range of 1 kHz to 35 MHz (-3 dB) establish new standards. Fig. 1 shows the HILL-SCAN 3010HF board with a length of 160 mm.  [c.856]

The HILL-SCAN 30XX boards can be used in different PCs. Desktop- and tower-PCs as well suited for laboratory uses. For in-field inspections rugged notebooks and portable PCs are advantageous. A typical portable system is shown in Fig. 2 (USPC 3010), used in MUSE (Mobile Ultrasonic Equipment). This portable PC not only contains the boards for ultrasonic testing but also a controller with power supply for stepper motors, so that a manipulator can be connected directly. The MUSE system is enlarged with a water circulation system which enables a local immersion technique" for in-field inspections. A typical result is shown in Fig. 3, which presents a D-scan of a CFRP- component in RTM-techniques. The defect area caused by an impact is clearly indicated. The manipulator is described in [3].  [c.859]

The great advantage of installing an ultrasonic system in a PC is that both the hardware (processor, grafics, power supply,. .) aud the software (evaluation and documentation) are directly available for the inspections.  [c.861]

EIOs), backward wave oscillators (BWOs) or magnetrons are available. Their spectral characteristics may be favourable however, they typically require highly stabilized high-voltage power supplies. Still higher frequencies may be obtained using far-infrared gas lasers pumped for example by a CO- laser [49].  [c.1585]

The p-n junction diode can also be used to convert optical energy directly to electrical power, without external power supplies. AbsorjDtion of a photon with E> E produces an e -h pair. The internal electric field of the p-n junction separates the carriers the eT and h move toward metallic contacts on opposite sides of the cell. The resulting photocurrent is sent to an external load. The maximum power delivered to a load is obtained under small forward bias. In Si cells, the largest voltage output produced in the open circuit mode (i.e. with /= 0) is about 0.7 V. Si solar cell power efficiencies as high as 24% have been reported, close to the theoretical limit of 32%. The power generated depends on the design of the diode itself and a match to the electrical load. The gap of the cell s semiconductor must match the solar spectmm as closely as possible and the stmcture of the gap should allow for efficient absorjDtion of the solar photons. Perfection of the semiconductor material is also very important for high efficiency. Electrons and holes generated far from the electrodes must be extracted from the bulk of the cell and this requires long minority carrier diffusion lengths.  [c.2890]

Limitations. The number of transistors present on a chip has doubled approximately every 18 months skice the kitegrated ckcuit was fkst developed (a rate of kicrease predicted by Gordon Moore of Intel Corporation ki 1960 that has become known as Moore s law). The main reason for this continuing decrease ki the minimum feature sizes of transistors (and consequent kicrease ki density of transistors on the chip) has been the development of photohthography, the prototypical reductive method (7,15,16,81—83). PhotoUthography creates patterns ki layers of siUcon, kisulators, and metals to produce the kitegrated ckcuit. For the accurate reproduction of features onto the siUcon wafer, the wavelength of light used must be at least as small as the smallest feature size (eg, feature resolution varies as the wavelength of light used and is kiversely proportional to the aperture of the objective lens and the depth of focus (DOF), requiring innovative solutions in planarization technologies and mask design). Other issues related to further scaling down of integrated ckcuits include the effects of power supply and threshold voltage of the transistors, short channel lengths, thickness of the gate oxide, high electric fields, fluctuations in the number of dopant atoms, and interconnect delays (7,84). The most important limitation for further size reduction, however, remains the development of new photo- and other Hthographic techniques.  [c.203]

A complete precipitator consists of (/) discharge electrodes, (2) collecting surfaces (plates or tubes), (2) a suspension and tensioning system for discharge electrodes, (4) a rapping system to remove dust from tubes, (5) dust hoppers and dust-removal system, 6) gas-distribution system and precipitator housing, and (7) power supply and control system. Single-stage precipitators are subclassified as plate or tube type. Typical arrangements are shown in Figure 10. A plate precipitator may have tall (10—15 m), parallel, flat plates with 228—400 mm hori2ontal spacing and discharge electrodes (wires) that are suspended midway between the plates. Plate precipitators are utili2ed for collecting flyash, for high gas-flow appHcations, and for particulates which are comparatively coarser than those caught in the tube-type equipment. Plate-type precipitators are lower in cost because both sides of the plate serve as precipitating surfaces. Tube precipitators are frequentiy used for Hquid mists and sometimes for submicrometer metallurgical fumes. Tubes vary in diameter from 150 to 304 mm a popular si2e is 273 mm OD by 4.5—5.0 m long. One discharge wire is centered in each tube. Dirty gas generally enters the hopper at the bottom and travels upward through the tubes. A tube sheet may be provided top and bottom tubes may be roUed or welded into a flat top tube sheet for a mist precipitator. For soHds, however, each tube must have a round to square transition at the top end. The tubes are then welded together to form an "egg-crate" sheet. Dust, if deposited on a flat tube sheet, can buildup with a nearly 90° angle of repose and short out the high tension support frame for discharge electrodes.  [c.398]


See pages that mention the term Power supplies : [c.20]    [c.69]    [c.571]    [c.857]    [c.415]    [c.464]    [c.601]    [c.174]    [c.662]    [c.870]    [c.870]    [c.918]    [c.918]    [c.290]    [c.343]   
Power supply cookbook (2001) -- [ c.0 ]