Design parameters Grounding

These are protection CTs lor special applications such as biased differential protection, restricted ground fault protection and distance protection schemes, where it is not possible to easily identify the elass of accuracy, the accuracy limit factor and the rated burden of the CTs and where a full primary fault current is required to be transformed to the secondary without saturation, to accurately monitor the level of fault and/or unbalance. The type of application tind the relay being used determine the knee point voltage. The knee point voltage and the excitation current of the CTs now form the basic design parameters for such CTs. They are classified as class PS CTs and can be identified by the following characteristics ... 

Since there are too many variables and parameters related to a grounding station, the following practical example illustrates a step-by-step procedure to design a grounding station. 

Determination of initial recovery well (or trench) locations is an important design parameter. Floating LNAPL product tends to move in the direction of overall ground-water flow, as determined by the water table gradient. As a well or trench is pumped, the fluids (water and/or oil) migrate toward the area of lower pressure to fill the void. A cone of depression develops that extends outward. The fluid surface exhibits a rapid slope near the well, diminishing to a very low gradient at a distance. 

The performance of immobilized and freely suspended affinity adsorbents was compared by calculating adsorption rates and selectivities for four different bead geometries. Simulation results indicate that the performance of finely ground adsorbent particles immobilized in hydrogel beads is superior compared to freely suspended adsorbents. The mathematical model was further used for simulation studies to investigate the effect of bead design parameters on product adsorption. 

This paper summarizes the design parameters, analytical methodology, fabrication process, and erection methodology for A-Frame structures, constructed of tapered steel box sections, in excess of 80 meters in height and used with ground mounted friction hoisting systems in Canada. The paper also evaluates alternative considerations for shop fabrication and erection of components weighing up to 200 tonnes, as well as the use of unique enclosed ropeway structures. 

GROUND INVESTIGATION DESIGN Equipment and Sampling In situ Testing Match to required design parameters... 

Performance-Based Design in earthquake engineering (SEAOC Vision 2000 1995, FEMA 273 1997) implies taking into account structural and ground motion uncertainties in order to obtain structural design parameters, satisfying multiple performance criteria with associated minimum reliability levels and (as an option) at a minimum total cost. 

This is the parameter that will help to decide the size and type of the grounding grid and design of the mesh. 

Chemical analyses should be provided for all anodes used in the offshore and harbor area, together with results for current content in A h kg and current output in amperes [2,3]. The geometric shape and the number of anodes required is determined by these parameters. Expensive calculations for design based on grounding resistances are made only in exceptional cases because in practice there are too many uncertainties and the number and mass of the anodes have to be quoted with a corresponding safety factor. 

First order parameters affecting dispersion stem from meteorological conditions. These, as much as any other consideration, determine how a stack is to be designed for air pollution control purposes. Since the operant transport mechanisms are determined by the micro-meteorological conditions, any attempt to predict ground-level pollutant concentrations is dependent on a reasonable estimate of the convective and dispersive potential of the local air. The following are meteorological conditions which need to be determined ... 

---