Normally closed circuits

FIG. 20" 7 Normal closed-circuit continuous grinding system with stream flows and composition matrices, obtained hy solving material-halance equations. [Callcott, Trans. Inst. Min. Metall., 76(1), Cl-11 (1967).]... 

Tumbling-Mill Circuits Tumbling mills may be operated in normal closed circuit, as shown in Fig. 20-45 or 20-59, or in reverse arrangement in which the feed passes through the classifier before entering the mill (see secondaiy mill in Fig. 20-44 or 20-59). 

Normally open means that when the unit is powered up it will not pass current through the trigger wire until the target material is detected. The normally-closed circuit configuration allows current to pass through the trigger wire until the target material is removed. 

In this circuit, the flow switch is connected to one side of power mains 225 by a conductor including a normally closed circuit breaker 333 adapted to be manually operated. The other side of the flow switch is connected to the magnetic clutch 232 and thence to the power main 225. As long as the proper amount of water is passing through the pipe 24, the flow switch 331 main-... 

Fire alarm circuits are wired as either normally open or normally closed. In a normally open circuit the alarm call points are connected in parallel with each other so that when any alarm point is initiated the circuit is completed and the sounder gives a warning of fire. In a normally closed circuit the alarm call points are connected in series to normally closed contacts. When the alarm is initiated, or if a break occurs in the wiring, the alarm is activated. 

In a normally closed circuit, the alarm call points are connected in series to normally closed contacts as shown... 

The three basic types of size reduction circuits used to produce a fine product ate shown in Eigure 1. The final stages of the grinding circuit are typically operated in closed circuit, at comparatively high circulating loads, so that the material has tittle chance of being broken a second time before it is removed from the circuit by a classifier. Rod mills are operated normally in an open circuit. 

The cardiovascular system includes the heart, which serves as a pump for the blood, and the blood vessels, which transport blood throughout the body. Under normal conditions, this system is a continuous, closed circuit, meaning that the blood is found only in the heart and blood vessels. 

S0LUTI0I1 The initial condition of the capacitor does not need to be specified because PSpice will determine the initial conditions from the circuit. The part name for the normally closed switch is N/C switch. 

In this section we will demonstrate the transient response of an inductor circuit with a switch that is normally closed. The initial condition of the inductor will not be specified by an IC= line in the circuit. Instead, the initial condition will be determined by PSpice from the initial state of the circuit before the switch changes position. If you wish to specify the initial condition of the inductor, it is specified in the same way as the initial condition of a capacitor. For an inductor, the direction for positive current is into the dotted terminal, as shown in Figure 6.1. The dot is always shown on the inductor graphic. The graphic should be rotated to obtain the desired direction of positive current flow. 

Pressure switches are used to energize and de-energize electrical circuits when the process pressure reaches their set points. The standard switch contact configurations are shown in Figure 3.143. The contacts are designated as normally open (N/O) and normally closed (N/C). In case of a single-pole double-throw (SPDT) switch, as the process pressure reaches the set point, the N/C contact opens and the common (C) side of the switch is closed to the contact designated as N/O. 

In closed-circuit milling, the tailings from a classifier are mixed with fresh feed and recycled to the mill. Calculations can be based on a material balance and an explicit solution such as Eq. (21-83a). Material balances for the normal circuit arrangement (Fig. 21-66) give... 

Capacitive sensors are one option for detecting the electrolyte level in the system. They have the ability to detect nonmetallic materials such as electrolyte solution and are available in either normal-ly-open (NO) or normally-closed (NC) circuit configuration. 

FIGURE 10.1 Flowsheet for the electric furnace process for the production of elemental phosphorus. Phossy water from the phosphorus phase separator (sump) is normally maintained in a closed-circuit holding pond system which also provides the feedwater for the phosphorus direct contact condenser. Some facilities have a further indirect, heat exchange condenser for the carbon monoxide stream, after the direct contact condenser. 

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