Core monitoring systems used

The core monitoring system originally was based on a Honeywell computer, the program for core monitoring system was based on the TIP readings and Local Power reading detectors, interpolation of the corrected reading were used to evaluate neutron flux and power distributions and from that thermal limits were derived. This first concept has not had prediction capability to evaluate some adjustment power manoeuvres. 

Many simple laboratory microcosms have been constructed primarily to assess the behavior of the chemical in both terrestrial and aquatic systems. Another approach has been to bring a piece of the environment into the laboratory. Soil cores have been used to monitor the fate of both inorganic and organic contaminants. A complex terrestrial microcosm will be described to illustrate what is involved in the design and operation of such a unit and the nature of the data generated. 

Using Siemens PLC as the core, designs the real-time monitoring system of the hoist braking system, which can be used as a staff member to management and maintenance of auxiliary hoist analysis tools. The main features include real-time online monitoring, human-computer interaction interface. 

The selection of the main controller Main controller is the core of the monitoring system, which determines the design of the hardware system and software system the whole monitoring system of So the type of main controller should be firstly determined, and then to determine the implementation scheme of the whole system based on the selection of main controller. Currently, microcontroller, DSP and programmable controller (PLC) is widely used. Having compared the performance of the three, PLC facilitate to the subsequent development of system, is more suitable in the mine production environment. So PLC is elected as main controller system. 

Laguna Verde Unit two started three fuel cycles after the unit one, during the construction process and start-up program of unit one some of the components of unit two were used as spare parts of unit one, for that reason during construction program of unit two such components were required but such components were out of the market, companies closed, or new advanced systems were developed for such purposes. That was the case of the Transverse In core Probe (TIP), Source (SRNM) and Intermediate range (IRNM) neutron monitoring systems. 

Resin Transfer Molding (RTM) The RTM system gives high quality surface on both the sides. A relatively low pressure (vacuum to 100 psi) process, RTM makes perfect shapes in 30 min to 1 h. The fabricator generally gel coats one or both mold halves, then lays continuous or chopped strand mat and the core, if used, into the bottom half, and closes the mold. The resin transfers into the mold through injection pressure, vacuum pressure, or both. Cure temperature depends on the resin system used. Heater blankets can heat the mold up to 202°C, if the matrix allows sensors to detect resin flow position in the mold and monitor resin and cure data [98]. 

In experimental systems in.stalled on bridges in the USA, sections of rebar have been isolated from the network and connected via an ammeter to the rest of the steel. This allows current flows into a particular area to be monitored. Similarly, an area of anode has been isolated and current flow measured to determine how much current the anode is delivering. The.se control and monitoring systems have been used in experimental system.s. In routine installations, none of this will be necessary. The amount of anode consumed can be assessed by occasional coring and the anode replaced when necessary. 

The IVMS is a monitoring system which generates data allowing detection of the motion of reactor internals. It uses linear summed detector signals from each of the ex-core neutron flux channels. The IVMS also has the capability to perform the analyses recommended by ANSI/ASME OM-5-1981. The system function, theory of operation and description are provided in CESSAR-DC, Section 7.7.1.6.1. [A related generic safety issue (GSI C-12) also addresses the IVMS.]... 

The core of the monitoring system is a multiphase model of the transport pipelines. This uses an widely-accepted simulation program called OLGA 2000. The principles behind this program have been described in detail elsewhere (Bendiksen, 1991, Scandpower 2001). 

Replacement of the existing boron meters with the new NAR-12 models which have increased measuring accuracy and the ability to monitor B-10 isotope. In addition, in order to have greater sensitivity immediately after replacement of 1/3 of the core, a new neutron monitoring system that uses new detectors (AKNP-7-02) with sensitivity and improved signal processing, displays and alarms are under development. 

The primary function of the in-core instrumentation system is to provide a three-dimensional flux map of the reactor core. This map is used to calibrate neutron detectors used by the protection and safety monitoring system, as well as to optimise core performance. A secondary function of the in-core instrumentation system is to provide the protection and safety monitoring system with the thermocouple signals necessary for the post-accident inadequate core cooling monitor. The in-core instrument assembhes house both fixed in core flux detectors and core exit thermocouples. 

The basic circuit of a circulating current earth monitoring system is shown in Fig. 3.2. It entails an extra core in the flexible cable. The step-down transformer s secondary winding circulates a current of a few milliamps at PELV through a contactor coil, the pilot core in the flexible cable, the protected apparatus and back to the transformer via the protective conductor. Any break in this circuit causes the contactor to open and to switch off the supply. The system is apphcable to multiphase systems also. If a braided armoured flexible cable is used, the armour can be employed as the... 

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