Control Gear Research Articles

Radiation characteristics of coaxial KrBr* excilamps based on a dielectric barrier discharge

The characteristics of the emission spectra of coaxial KrBr* excilamps driven by sinusoidal, rectangular and pulsed electronic control gear (ECGs) are investigated, based on the dielectric barrier discharge (DBD) with an annular gap of 10.5 mm. The radiant power of intense narrow band ultraviolet radiation at 207 nm is derived from the irradiance according to the Keitz formula, while the input power is computed from the integral of the product of voltage and current. The radiant characteristics of the 207 nm spectral line have been studied with regard to total pressure and bromine percentage, demonstrating an optimum pressure at 300–350 mbar as well as an optimum bromine percentage 0.1–0.3%, resulting in (3–4%) ± (0.3–0.5%) radiant efficiency at the optimum lamp power density of 360–540 W m−1. Of the three ECGs, results indicate that the pulsed waveform produces a higher efficiency than rectangular and sinusoidal waveforms.

Photo-dissociation of dimethylamine by KrBr* excilamp

A study of dimethylamine photo-dissociation in the gas phase has been conducted using UV radiation delivered from a KrBr* excilamp, driven by a sinusoidal electronic control gear with maximum emission at wavelength of 207nm. The electrical input power and radiant power of the lamp were measured to determine their effects on the degradation. The influence of flow velocity and initial concentration of dimethylamine were also examined. In order to evaluate the photo-dissociation process comprehensively, several parameters were investigated, including removal efficiency, energy yield, carbon balance and CO2 selectivity. It is shown that the removal efficiency increases with enhanced input power and decreased gas flow rate. A high removal efficiency of 68% is achieved for lamp power 102W and flow velocity 15m3h−1. The optimum dimethylamine initial concentration is around 3520mgm−3, for which the energy yield reaches up to 442gkWh−1 when the input power is 65W. In addition, two chain compounds (1,3-bis-dimethylamino-2-propanol; 3-penten-2-one, 4-amino) and three ring organic matters (1-azetidinecarboxaldehyde, 2,2,4,4-tetramethyl; N-m-tolyl-succinamic acid; p-acetoacetanisidide), were identified by GC–MS as secondary products, in order to demonstrate the pathways of the dimethylamine degradation.

ICME Tools Can Help Control Gear Distortion from Heat Treating

Abstract Engineers at the Ford Motor Co. are using integrated computational materials engineering (ICME) tools, allowing them to accurately simulate the heat treatment of gears and predict phase transformation kinetics and distortion.

Comparison of electronic and conventional ballasts used in roadway lighting

Although manufacturers recommend light-emitting diode technology for all types of urban lighting, it is likely that high-pressure sodium lamps will be used for roadway lighting for many years. The purpose of this paper is to establish whether electronic ballasts represent a better solution for such lamps than electromagnetic ballasts. Special attention was devoted to the fact that electronic ballasts allow considerably higher voltage drops. However, taking into account the earth-fault protection demands, it is shown that electronic ballasts provide only a modest possibility to increase the length of the street lighting section. The techo-economic analysis showed that, owing to the high prices and shorter life of electronic ballasts, conventional electromagnetic control gear still represents a better choice from the financial point of view.

Life cycle assessment of a fluorescent lamp luminaire used in industry – a case study

Environmental impacts of light sources and control gears have been analysed in several life cycle assessments (LCAs). In contrast, this paper analyses the environmental impacts of an entire fluorescent lamp/luminaire combination. The environmental impacts of a fluorescent lamp luminaire with two T5 lamps and an electronic ballast are analysed in a variety of potential environmental impacts. The results show that the energy consumption during use dominates the total environmental impacts by 93% on the average, while manufacturing accounts for 7% and end-of-life less than 1%. The importance of energy consumption is dependent of the used energy source. Compared to a previous LCA of fluorescent lamp luminaire, the division of the results into life cycle stages is similar but there are differences in the numerical results.

Based on ANSYS Controllable Start Planet Gear Reducer Planet Carrier Modal Analysis

The software of ANSYS for controllable start planet gear reducer type differential vibration characteristics and response characteristics of a more comprehensive analysis, the planet carrier of the first six vibration modes cloud and test results verify the correctness, so as to avoid resonance due to plant damage caused by such factors as a reference in theory, but also for the further study of controllable start planet gear reducer of the vibration of the differential to provide a theoretical reference.

Free-Form Flank Correction in Helical Gear Grinding Using a Five-Axis Computer Numerical Control Gear Profile Grinding Machine

To reduce form grinding errors, this paper proposes a free-form flank topographic correction method based on a five-axis computer numerical control (CNC) gear profile grinding machine. This correction method is applied not only to the five-axis machine settings (during grinding) but also to the wheel profile (during wheel truing). To achieve free-form modification of the wheel profile, the wheel is formulated as B-spline curves using a curve fitting technique and then normal correction functions made up of four-degree polynomials are added into its working curves. Additionally, each axis of the grinding machine is formulated as a six-degree polynomial. Based on a sensitivity analysis of the polynomial coefficients (normal correction functions and CNC machine settings) on the ground tooth flank and the topographic flank errors, the corrections are solved using the least squares method. The ground tooth flank errors can then be efficiently reduced by slightly adjusting the wheel profile and five-axis movement according to the solved corrections. The validity of this flank correction method for helical gears is numerically demonstrated using the five-axis CNC gear profile grinding machine.

Application of Pro/E in the Design of the Controllable Start Planet Gear Reducer

The application of Pro/E in three-dimensional parametric modeling in the controllable star[planet gear reducer,and the application of Relations,program of Pro/E in parametric design of the gear were introduced.The components assembly design was described.The basal essential in parameterized modeling with Pro/E was introduced.

Development of a bycatch reduction device (BRD) for shrimp beam trawl using flexible materials

This study aimed to design a bycatch reduction device (BRD) for shrimp beam trawl, which is manufactured by flexible materials to reduce bycatch for the gear in the South Sea of Korea. The model test was carried out to understand the shape of the gear in the water and to measure the variation of flow speed due to the BRD in a circulating water channel. Catches were compared between a shrimp beam trawl without BRD (control gear) and others with BRD (treatment gears) in the field. BRDs were two different types in this study. In the case of BRD (a), a square-shaped grid net and a funnel-shaped net were installed in the front part of the cod end to help fish sorting and expelling through the outlet at the bottom. BRD (b) has one more outlet which is added at the upper part of the BRD (a). On the model test, water speed was reduced a little in the gear by installing the BRD. At the results of comparing with a control gear, the bycatch (%) of fish excluding shrimp was reduced between 17 and 68% using BRD (a) and 5 and 66% for BRD (b) respectively. By the signed test of significant level 0.05, the quantity of shrimp catches for BRD (a) was not different in comparison to the control gear but it decreased for the gear installing BRD (b).

Trend of Standardization for LED Light Sources and Control Gears for General Lighting

Trend of Standardization for LED Light Sources and Control Gears for General Lighting

A flank correction methodology for a five-axis CNC gear profile grinding machine

Form grinding is the most popular finishing process for large-size gear because of its high accuracy, efficiency, and flexibility in tooth flank modification. Theoretically, this tooth flank topographical modification is calculated using loaded tooth contact analysis (LTCA), which takes into account the gear tooth, shaft, and housing deflections. Such topographical modification, however, is difficult in the existing gear form grinding method. To simplify production of the ground tooth flank topography, this paper proposes a tooth flank modification grinding method with high-order correction based on the degrees of freedom in the five-axis computer numerical control (CNC) gear profile grinding machine. Each axis of the grinding machine is formulated as a high-order polynomial, and the sensitivity of the polynomial coefficient is derived based on the topographic normal deviation on the gear tooth flank. The ground tooth flank can be approximated to the theoretical tooth flank by adjusting the coefficients of the polynomials based on their sensitivity. We demonstrate the validity of this flank correction method numerically using a helical gear made by the five-axis CNC gear profile grinding machine.

Arc-Resistant Equipment

Because of the recent focus on arc flash hazards, arc-resistant equipment is becoming increasingly common in industrial facilities throughout North America. This article addresses arc-resistant equipment as it applies to low-voltage motor control centers (LVMCCs) [National Electric Manufacturing Association (NEMA) 600 V LVMCC/International Electrotechnical Commission (IEC) 690 V LV control gear}. A brief overview and history of applicable internal arc fault testing guides (IEEE C37.20.7 and IEC/TR 61641) are included. Test procedures and their considerations as well as arc-resistant assessment criteria are reviewed. An examination of various methods to achieve an arc resistant rating (device-limited rating and duration rating) as well as considerations for implementing arc-resistant equipment are addressed.

Determining the fuel savings potential of parallel hybrid hydraulic vehicles

In this paper, the fuel savings potential of parallel hybrid hydraulic vehicles with (automated) manual transmission is assessed. An adapted model of a hybrid hydraulic truck is used to compute the optimal control strategy for a given velocity profile as a reference. Special care is given to include practical conditions in the optimisation framework so that realistic trajectories are calculated, and to integrate the effects of clutch operation into the set-up. Previous works of other authors are employed to define a baseline power management strategy. Several elements of the optimal control (gear shifts, clutch operation, torque distribution) are analysed and compared with the baseline strategy to assess the major differences and the possible realisation of the remaining fuel savings potential. On the basis of the corresponding findings, a new approach to design a realistic, predictive supervisory control is developed and the potential of the new concept is demonstrated.

Counterfeit and non-compliant electrical products

The market in counterfeit watches, designer clothes, CDs and DVDs has enjoyed widespread publicity. But the market in counterfeit electrical installation products is far more serious because it may involve...

Best Available Technology: Make the Right Choice

This article states that the best available technology isn't always affordable, so a good substitute is educating yourself by attending seminars, meetings, and conferences to share ideas and learn. The author recommends taking time to study and learn from other systems and operators, and read articles in trade journals dedicated to improving water quality. Operators know the inner workings of their systems better than anyone. Only operators can tweak a chlorinator or fool a control gear to get optimal results. By learning what's available, what works, and why it works, operators can educate others.

The efficiency of coaxial KrCl* excilamps

The spectrum, input power and 222 nm radiant efficiency were measured for coaxial KrCl* excilamps based on a dielectric barrier discharge. The inner tubes of the lamps have an inner/outer diameter (ID/OD) of 14/16 mm. The OD of the outer tubes is 40 mm with wall thicknesses of 1.2, 1.5 or 2.0 mm. The lamps were driven by sinusoidal, rectangular and pulsed electronic control gears (ECGs). The 222 nm radiant power is derived from irradiance, according to the Keitz formula. The input electric power is measured with an oscilloscope, combined with a voltage probe and a current probe. The results show that the maximum efficiency of the 222 nm radiation is 9.2% for a KrCl* excilamp with a wall thickness of 1.2 mm, filled with krypton (198 mbar) and chlorine (2 mbar), driven by a pulsed ECG. The effects of waveform, frequency, wall temperature and transmittance of the tube are discussed. We observe that the filament configuration of the micro-discharges changes for different voltage waveforms. The results of gas composition and pressure show an optimum pressure at 200 mbar and an optimum chlorine percentage around 0.4–1.0%.

Influence of Wind Turbulence on Yaw-control Gears in Wind Turbine

This paper describes an influence of wind turbulence on yaw-control gears of nacelle in a wind power station. This site is located in Tappi cape of Aomori prefecture where is characterized by a big wind turbulence due to the western strong wind and a steep slope of the cape. In this paper two adjacent wind towers are dealt with among eleven ones. To clarify an influence of the wind turbulence on the leeward wind power generator. The measurement results showed that the turbulence and the standard deviation exceeded IEC Wind Turbine Standards frequently. Accordingly the torque applied to the yaw control gears vibrated with short time period and its magnitude was frequently larger than 4.8 ton-m (47kN-m) regarded as the metal fatigue limit. By the method where the output of the wind turbine generator is controlled, the magnitude of the vibrating torque can be reduced under the limit of the material fatigue.

The Energy and Financial Impacts of High-Intensity Discharge Lighting System Component Selection and Luminaire Maintenance in Industrial Lighting Applications

Electric lighting is responsible for consuming approximately twenty-two percent of the electrical energy generated domestically, second only to that consumed by electric machinery. Of this quantity, approximately fifteen percent of the lighting energy usage is by those lighting products that fall within the category termed High-Intensity Discharge (HID). HID sources, which include Mercury Vapor, Metal-Halide, and High-Pressure Sodium, range in power level from 35 to 2000 watts. Luminaires equipped with these sources are used in outdoor lighting applications and also indoor applications, one category of which is the focus of this article - the illumination of industrial facilities. The term “lighting system” is used in this article to describe all of the elements required to illuminate the target area to required levels. This includes lamps, ballasts, housings, optical assemblies, support structures, and any other components involved in the operation and maintenance of the lighting system.Efforts to reduce energy consumption most often revolve around the use of more efficient or efficacious lighting products which will be successful in providing the desired photometric results. In general, the more efficient the system in converting electrical energy to visible energy, the more expensive are the source and associated control gear. Consequently, the relationship between acquisition cost and performance is a major obstacle in an effort to convince users to install more efficient lighting equipment. This article reviews the performance characteristics of the various HID lamp families that are used domestically in industrial lighting applications. This includes selected energy consumption profiles, cost breakdowns, and life-cycle cost analyses of various HID lighting systems for the purpose of offering guidance to those who are responsible for the selection and application of lighting products. Also provided is an in-depth investigation into the impact of lighting system maintenance upon the energy consumption and overall cost of a lighting project as projected using life-cycle costing techniques.

Influence of electrode, buffer gas and control gear on metal halide lamp performance

In this paper the influence of electrode composition, buffer gas fill pressure and control gear on the performance of metal halide lamps is investigated. It is shown that pure tungsten electrodes improve lumen maintenance and reduce voltage rise over lamp life. An optimum buffer gas fill pressure condition is discovered which allows for reduced electrode erosion during lamp starting as well as under normal operating conditions. Use of electronic control gear is shown to improve the performance of metal halide lamps.

Modelling the contact probability and size-selectivity of toothed dredges

To estimate fishing gear selectivity of clam dredges from data of paired-gear tests in the SELECT analysis process, this paper presents a statistical model of the probability of a clam coming into contact with the dredge teeth and size-selectivity of the control gear. The net-mouth available selectivity is defined as the product of the probability of a clam contacting the dredge teeth and size-selectivity induced by tooth spacing. The model based on the SELECT analysis was tested by using data generated by virtual paired-gear test in which the control dredge of the smallest tooth spacing is assumed to be size-selective. No clear difference in shell length distribution between dredges of different tooth spacings was found in the simulation when the contact probability was small. The plots of proportion of clams caught in the test dredge to the total catch number of clams were U-shaped, and the model fitted the data well. For each simulation consisting of 500 replications, the sample mean and mean square error of each parameter were obtained to evaluate the performance of estimation by comparing with the true value. Parameters were properly estimated with the model.