The Experts below are selected from a list of 51 Experts worldwide ranked by ideXlab platform
William Bolton - One of the best experts on this subject based on the ideXlab platform.
-
Chapter 7 – Internal Relays
Programmable Logic Controllers, 2009Co-Authors: William BoltonAbstract:Publisher Summary This chapter discusses programming and introduces Internal Relays. A variety of other terms are often used to describe these elements, such as auxiliary Relays, markers, flags, coils, and bit storage. These are one of the elements included among the special built-in functions with PLCs and are very widely used in programming. A small PLC might have a hundred or more Internal Relays, some of them battery backed so that they can be used in situations where it is necessary to ensure safe shutdown of a plant in the event of power failure. With ladder programs, an Internal Relay output is represented using the symbol for an output device, namely ( ), with an address that indicates that it is an Internal Relay. The Internal Relay switching contacts are designated with the symbol for an input device and given the same address as the Internal Relay output. Internal Relays that are battery-backed are able to retain their setting, even when the power is removed. The Relay is said to be retentive.
-
Chapter 11 – Shift Registers
Programmable Logic Controllers, 2009Co-Authors: William BoltonAbstract:Publisher Summary The term register is used for an electronic device in which data can be stored. An Internal Relay is such a device. The shift register is a number of Internal Relays grouped together that allow stored bits to be shifted from one Relay to another. This chapter discusses shift registers and how they can be used when a sequence of operations is required or to keep track of particular items in a production system. With the shift register it is possible to shift stored bits. Shift registers require three inputs: one to load data into the first location of the register, one as the command to shift data along by one location, and one to reset or clear the register of data. The grouping together of Internal Relays to form a shift register is done automatically by a PLC when the shift register function is selected.
-
7 – Internal Relays
Programmable Logic Controllers, 2006Co-Authors: William BoltonAbstract:Publisher Summary This chapter provides an introduction to Internal Relays, which are often known as auxiliary Relays, markers, flags, coils, and bit storage. These elements give special built-in functions to a programmable logic controller (PLC) and are very widely used in programming. A small PLC might have a hundred or more Internal Relays, some of them being battery backed, so that they can be used in situations where it is necessary to ensure safe shutdown of a plant in the event of a power failure. While using an Internal Relay, it has to be activated on one rung of a program, and then its output is used to operate switching contacts on another rung, or rungs, of the program. Internal Relays can be programmed with as many sets of associated contacts as desired. To distinguish Internal Relay outputs from external Relay outputs, they are given different types of addresses. With ladder programs, an Internal Relay output is represented by using the symbol for an output device with an address, which indicates that it is an Internal Relay rather than an external Relay. Another use of Internal Relays is for resetting a latch circuit.
-
11 – Shift registers
Programmable Logic Controllers, 2006Co-Authors: William BoltonAbstract:Publisher Summary This chapter discusses the shift registers and how they can be used where a sequence of operations is required or to keep track of particular items in a production system. The shift register is a number of Internal Relays grouped together that allow stored bits to be shifted from one Relay to another. Each Internal Relay is either effectively open or closed, these states being designated as 0 and 1. The term bit is used for each such binary digit. With the shift register, it is possible to shift stored bits. Shift registers require three inputs, one to load data into the first location of the register, one as the command to shift data along by one location, and one to reset or clear the register of data. The grouping of Internal Relays to form a shift register is done automatically by a programmable logic controller (PLC) when the shift register function is selected. With the Mitsubishi PLC, this is done by using the programming code SFT (shift) against the Internal Relay number that is to be the first in the register array. This then causes a block of Relays, starting from that initial number, to be reserved for the shift register.
Glenda M. Halliday - One of the best experts on this subject based on the ideXlab platform.
-
Comparison of the basal ganglia in rats, marmosets, macaques, baboons, and humans: Volume and neuronal number for the output, Internal Relay, and striatal modulating nuclei
The Journal of Comparative Neurology, 2002Co-Authors: Craig D. Hardman, Jasmine M. Henderson, David Finkelstein, Malcolm K. Horne, George Paxinos, Glenda M. HallidayAbstract:This study compares the basal ganglia of rats, marmosets, macaques, baboons, and humans. It uses established protocols to estimate the volume and number of neurons within the output nuclei (Internal globus pallidus, IGP; and nondopaminergic substantia nigra, SNND), two Internal Relay and modulating nuclei (subthalamic nucleus, STh; and external globus pallidus, EGP), and a modulator of the striatum (dopaminergic substantia nigra, SND). Nuclear boundaries were defined by using immunohistochemistry for striatal afferents. Total numbers of Nissl-stained and parvalbumin-immunoreactive neurons were calculated by using the fractionator technique. Comparisons between species were standardized relative to brain mass (rats < marmosets < macaques < baboons < humans). The EGP consistently had more neurons relative to the IGP, STh, and SND, which had similar neuronal numbers within each species. The SNND had proportionally more neurons in rats than in primates (especially humans). The distribution of SND neurons varied substantially between rats and primates (very few ventrally located neurons in rats) with humans containing fewer SND neurons than other primates. The reduction in SND neurons in humans suggests less dopaminergic regulation of the basal ganglia system compared with other species. The consistency in the number of IGP neurons across all species, combined with the reduction in SNND neurons in humans, suggests a greater emphasis on output pathways through the IGP and that there are proportionally more STh and EGP neurons in humans.
Gao Min - One of the best experts on this subject based on the ideXlab platform.
-
Optical design of panoramic system based on distributed aperture concept
Journal of Applied Optics, 2010Co-Authors: Gao MinAbstract:In order to overcome the weaknesses of observation and detection systems in tanks,such as inefficiency and inaccuracy,the design of the panoramic optical systems based on the distributed aperture concept was performed,whose principle is to implement the real-time collection of the panoramic image information covering 360°space in utilizing four objectives of aperture greater than 90°,integrate the collected four-path images into one path by the Internal Relay system,receive the image information by a CCD camera,provide the images spliced with the accurate and uniform panoramic images,estimate under ideal situation the parameters such as detection distance,recognition distance and blind spots,and then estimate the invalid detecting distance by the aid of ray tracing.Panoramic optical systems can realize the all-dimensional real-time observation and detection at the working distance of 57m～6.45km.
Bo Zhiqian - One of the best experts on this subject based on the ideXlab platform.
-
Cooperation of Relay protection for grid-connected wind power with low-voltage ride-through capability
Electric power automation equipment, 2012Co-Authors: Bo ZhiqianAbstract:The wind turbine with low-voltage ride-through capability is required not to disconnect from grid under certain fault conditions,for which the relevant Relay protections should cooperate with it.The cooperation between the Relay protection of transmission system beyond the wind farm outgoing line and the Relay protection of wind farm is analyzed for different faults of transmission system components,wind farm outgoing line,wind farm Internal grid and wind turbine.The current configuration of Relay protection for the wind farm centrally connected to power grid is analyzed and it is pointed out that,the selectivity of wind turbine protection and converter protection is not enough,which leads to the disconnection of wind farm from grid before the fault is removed by wind farm Internal Relay protection or system Relay protection,and the current configuration regards the wind power as a distribution network with single source,which neglects the contribution of wind turbine to short-circuit fault.Improvements are proposed for the Relay protections of wind turbine,main transformer and outgoing line to ensure the successful low-voltage ride-through,and their problems are pointed out.
Craig D. Hardman - One of the best experts on this subject based on the ideXlab platform.
-
Comparison of the basal ganglia in rats, marmosets, macaques, baboons, and humans: Volume and neuronal number for the output, Internal Relay, and striatal modulating nuclei
The Journal of Comparative Neurology, 2002Co-Authors: Craig D. Hardman, Jasmine M. Henderson, David Finkelstein, Malcolm K. Horne, George Paxinos, Glenda M. HallidayAbstract:This study compares the basal ganglia of rats, marmosets, macaques, baboons, and humans. It uses established protocols to estimate the volume and number of neurons within the output nuclei (Internal globus pallidus, IGP; and nondopaminergic substantia nigra, SNND), two Internal Relay and modulating nuclei (subthalamic nucleus, STh; and external globus pallidus, EGP), and a modulator of the striatum (dopaminergic substantia nigra, SND). Nuclear boundaries were defined by using immunohistochemistry for striatal afferents. Total numbers of Nissl-stained and parvalbumin-immunoreactive neurons were calculated by using the fractionator technique. Comparisons between species were standardized relative to brain mass (rats < marmosets < macaques < baboons < humans). The EGP consistently had more neurons relative to the IGP, STh, and SND, which had similar neuronal numbers within each species. The SNND had proportionally more neurons in rats than in primates (especially humans). The distribution of SND neurons varied substantially between rats and primates (very few ventrally located neurons in rats) with humans containing fewer SND neurons than other primates. The reduction in SND neurons in humans suggests less dopaminergic regulation of the basal ganglia system compared with other species. The consistency in the number of IGP neurons across all species, combined with the reduction in SNND neurons in humans, suggests a greater emphasis on output pathways through the IGP and that there are proportionally more STh and EGP neurons in humans.