Auxiliary circuit

All the CT (current transformer) secondaries must be shorted and grounded while conducting the test on the main circuit. This condition is redundant while conducting test on the auxiliary circuit. 

Table 14.3 For series I voltage systems. Dielectric test voltages for control and auxiliary circuits and also LT power circuits...

No water droplets can be observed on the insulation of the main and auxiliary circuits... 

In Europe and Asian nations this is generally 110 or 110/ 2 V. (62.5 V) for phase-lo-phase or phase-lo-grotmd auxiliary circuits respectively. In the U.SA and Canada these voltages are 120 oiy l20/v2 V for distribution systems and 115 or 115/ v 2 V for transmission systems,... 

The total VA level of a control or an auxiliary circuit is the phasor sum of the VA burdens of each individual component and device connected in the circuit, and... 

Split-Phase Motor. A split-phase motor is a single-phase induction motor equipped with an auxiliary winding, displaced in magnetic position from, and connected in parallel with, the main winding. Note Unless otherwise specified, the auxiliary circuit is assumed to be opened when the motor has attained a predetermined speed. The term split-phase motor, used without qualification, described a motor to be used without impedance other than that offered by the motor windings themselves, other types being separately defined. 

Resistance-Start Motor. A resistance-start motor is a form of split-phase motor having a resistance connected in series with the auxiliary w inding. The auxiliary circuit is opened when the motor has attained a predetermined speed. 

When the plant is located in built-up areas, there might also be an atmospheric condenser that receives the steam, which is vented during the startup to decrease the noise level at the plant. The auxiliary circuits of the steam turbine are the lube oil, control fluid, and vacuum system for the condenser. 

The plug and socket according to Fig. 6.142 shows a coaxial arrangement of the contacts of a three-phase system. The central multi-contact pin is intended for six pilot and auxiliary circuits. Plug and socket are fixed together by means of a special fastener. 

Alternatively, one may polarize the platinum disk to the quinone-hydroquinone equilibrium potential with the help of a current supplied by an auxiliary circuit. Then one may determine the required current 7, and the rate of consumption of quinone or the rate of formation of hydroquinone. At the quinone-hydroquinone equilibrium potential the electrochemical reduction of hydroquinone vanishes. Consequently, a finite rate of the formation of hydroquinone at the quinone-hydroquinone equilibrium potential equals the partial rate due to the nonelectrochemical mechanism according to Eqs. (VIII.lla)-(VIII.11c). 

Energising a downstream switchboard throngh a transformer or plain interconnector. The upstream switching device is closed first. The downstream device is then closed. If either trips on fault then the other may be caused to trip by auxiliary circuits and relays. 

The problems described in the previous section are largely overcome by the introduction of a third electrode into the circuit (Fig. 1.2b). An auxiliary circuit, often termed a potentiometer circuit, has been added to the previous two-electrode circuit. The cell current still passes between the WE and the SE in the primary circuit and the cell voltage (F) is still developed between these electrodes. We still have ... 

Consider the auxiliary circuit comprising the WE, the reference electrode (RE) and a high impedance voltmeter (HIV). If P is the potential difference measured by the HIV then ... 

A suitable circuit is that shown in Fig l,2d. Potentiostatic control is achieved by means of the auxiliary circuit shown in Fig. 1.2b and 1.2d. The reading on the high impedance voltmeter (F) has the significance of ... 

The PFR primary cold trap loop (PCTL), shown in Figure 5.1, is an auxiliary circuit connected to the primary circuit. It purifies the active sodium by removing impurities. 

As the main pollutant of the secondary circuit is hydrogen, the secondary auxiliary circuits have to be optimised in order to measure hydrogen contents and in order to trap hydrides it would be useful to have data about tritium diffusion from the primary circuit. 

Thermal striping has been the cause of some of the sodium leaks in auxiliary circuits. Mixing devices has been provided to ensure that sodium streams mix with temperature differences lower than the established safe limits. 

Last, it should be stated that the return to operating conditions illustrates the great importance of having valves that function properly and reliably and the need to monitor them along with the advantage of simplification in the auxiliary circuits. 

This document describes the operations to be performed to dismantle the secondary and auxiliary circuits on the Creys-Malville power station. The period covers the disposal of these circuits, from their post-operation status, i.e., secondary sodium drained and circuits maintained under a neutral gas, until complete dismantling of the installations. The problems involved in sodium circuit treatment are more specifically described, and notably the preliminary interventions to materially separate the secondary zones from the primary-reactor zones and to prepare for the treatment of the residual sodium. 

The choice of the carbonation operation is based on experience feedback from secondary pipework treatment operations for inspection and carbonation of the SPX irradiated assemblies storage tank on the Phenix power station at the time of its dismantling. The carbonation of the pipework residual sodium therefore constitutes the reference solution for the treatment of secondary and auxiliary SPX circuits. However, it was decided to engage a demonstration site for treatment of an auxiliary circuit by the carbonation process. The selected auxiliary circuit has been in a so-called fossil condition since 1992. Today, this circuit has been partly dismantled and comprises several parts drained and maintained under inert gas. It consists of two identical and independent loops whose main characteristics are as follows ... 

Materially engage the auxiliary circuits dismantling operations. 

The dismantling operations on the heat evacuation circuits (secondary and auxiliary circuits). 

Fixed-volume and variable-volume pumps are the two types commonly applied in the press application. Fixed-volume pumps are normally vane type and are used for fixed-speed presses and for auxiliary circuits such as filtering, cooling, and pilot pressure. Variable-volume pumps are normally radial or axial piston type and are used for variable pressing speeds and pressure compensated circuits. 

Auxiliary circuits are those not directly producing the activity of the main slide of the press. Usually, these circuits have dedicated pumps to provide hydraulic pressure and flow to accomplish an auxiliary task or function that is independent from the main press action. Some examples include pilot pressure, filtering, cooling, cushion, ejector, blankholder, or other auxiliary actions. As with the main circuit, the auxiliary circuit can be equipped with a fixed-volume or a variable-volume pump, depending on the requirement. 

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