Surges diverters

High boron content, low melting tenqtera- Discharge lamps, surge diverters... 

Loss-of-excitation protection in installations where there is a risk of high overvoltages, a surge diverter is to be installed and, in certain cases, protective capacitors... 

Arresters or diverters are generally of the following types and the choice between them will depend upon the power frequency system voltage, characteristics of the voltage surges and the grounding system, i.e. 

Premixed formulation (1) is fed into a surge (day) bin (2). Recycled material (fines, 17) and dust from the dust-collection system (20) are transported to the bin (18). The latter should be sized such that, in the case of an emergency or unscheduled switchover, the entire hold-up of the plant can be accepted. If a new formulation must be run, the contents of the recycle bin (18) can be dumped via the diverter gate (19). 

A surge protection device is a device intended to limit transient over-voltages, and to divert damaging surge currents away from sensitive equipment. 

E. Dechlorinated Brine Surge Tank. If the depleted brine receiver cannot hold the volume required to flush the ceUs during the rectifier shutdown, a surge tank of sufficient volume is necessary (Fig. 11.17). The brine collected in this tank can be returned to the brine system at a controlled rate. The same tank can receive brine diverted from the process for other reasons. The diversion system shown here consists of a pair of on-off valves, one in the brine line after the neutralization system and the other in the line to the dechlorinated brine hold tank. Dechlorinated brine ean be diverted into this tank manually or automatically. Reasons for automatic diversion include power failure and insufficient dechlorination. 

The leak monitoring system must therefore be supplied with equipment which can divert voltage surge on the buried components and protect people and the control and assessment system. An independent expert inspector must have examined and reported on the lightning prevention equipment. 

SPD absorbs and diverts the extra current to ground to protect electronic instrumentation and control (I. C) devices from surge or transient. 

Fig. APII/4.1.3-1 shows the typical configuration for SPDs. As seen in the figure, there is protection both in differential mode (line to line) and common mode (line to earth). GDT, discussed previously, provides the first switching action to divert high voltage and current. Second elements comprising TVS provides the second line of defense especially for slower responding surges. Inductors are used to decouple the two protection stages. Basic purpose and functioning of various components have already been discussed in previous clause.

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