Solid state relay

Programmable Logic Controllers The programmable logic controller (PLC) originated as a solid-state replacement for the hardwired relay control panel and was first used in the automotive indus-tiy for discrete manufacturing control. Today, PLCs are used to implement Boolean logic functions, timers, counters, and some math functions and PID control. PLCs are often used with on/off process control valves. 

Programmable Logic Controller (PLC) A microcomputer-based solid-state control system which receives inputs from user-supplied control devices such as switches and sensors, implements them in a precise pattern determined by instructions stored in the PLC memory, and provides outputs for control or user-supplied devices such as relays and motor starters. 

The follow ing are the normal protections that may be available in both-a solid-state ora microprocessor-based relay, making them a single-device protection ... 

With application of solid-state technology, this shortcoming of an electromagnetic relay is automatically overcome. The solid-state relays are available with switching stages as many as from 2 to 16. For special applications, they can be designed for even higher numbers of steps. 

The above discussion is generally related to IC-based solid-state relays and in most parts to microprocessor-based relays of tbe more rudimentary types. 

Gemini North Observatory/CTI Mode-locked SFG Laser. CTT is developing the first commercial solid-state Na LGS system. It will be installed on the center section of the 8-m Gemini North telescope, with the output beam relayed to a projector behind the secondary mirror. The projected beam is required to be 10-20 W power, with M2 < 1.5. The architecture is based on sum-frequency mixing two mode-locked solid-state Nd YAG lasers. The mode-locked format provides significantly higher peak intensity than CW, enabling more efficient SFG conversion. The laser is also free of the thermal and intensity transients that are inherent in the macro pulse format. The chosen... 

The DAC system consisted of computer, interface cards, meters, transmitters, and solid state relays (SSR). Electrodes of pH (Ingold), Oxidation-Reduction Potential (Cole-Parmer), and Dissolved Oxygen (Ingold) were installed and connected to individual meter. The status of reactor and the value of electrode signal were displayed in a computer monitor, and stored in data file. 

Four different types of tasks are performed by automation. Two involve the sequencing of valves and pumps Involved 1n the setup and completion of the designed experiment through the operation of the test and hydraulic fluid systems. The other tasks involve the control of the temperature bath and data collection. To perform these tasks, a1r-actuated solenoids and optically coupled sol Id-state relays are used. These devices are controlled by an electrical circuit consisting of the device connected 1n series with a power supply and a channel on the actuator card In the HP 3497. The power supply 1s either 24 VDC for use with the solenoids or 5 VDC for the solid-state relays. The actuator output channel acts as a simple on/off switch which allows power to be supplied to the solenoid or relay when closed. The logic of the circuit 1s controlled by application programs running on the local HP 1000. 

Bill, I think this is a multivibrator and not a relay at all. It was the pre-solid state method of making an AC signal out of a DC input, probably from an old telephone system or vacuum tube driver. You will note that there are no connections from the coils to any of the terminals, except through the contacts (I expect the coils are connected to their respective end contacts). So both contacts on one side will be closed to complete a circuit - when power is applied these contacts will open and the opposite pair close and it just keeps doing this at its resonate frequency. There is one thing for sure - it is not operating as a relay in any way at all. 

V (usually DC but sometimes AC) Switched Typically up to 240V AC only SSR (solid-state relay or triac)... 

Supervisory control and data acquisition Solid-state relay Self-tuning regulator Temperature recorder controller Transistor-transistor logic Zero order hold element... 

II Moderate immunity Electronic ballasts, solid-state relays, programmable logic controllers, adjustable speed drives... 

Several studies have tackled the structure of the diketopiperazine 1 in the solid state by spectroscopic and computational methods [38, 41, 42]. De Vries et al. studied the conformation of the diketopiperazine 1 by NMR in a mixture of benzene and mandelonitrile, thus mimicking reaction conditions [43]. North et al. observed that the diketopiperazine 1 catalyzes the air oxidation of benzaldehyde to benzoic acid in the presence of light [44]. In the latter study oxidation catalysis was interpreted to arise via a His-aldehyde aminol intermediate, common to both hydrocyanation and oxidation catalysis. It seems that the preferred conformation of 1 in the solid state resembles that of 1 in homogeneous solution, i.e. the phenyl substituent of Phe is folded over the diketopiperazine ring (H, Scheme 6.4). Several transition state models have been proposed. To date, it seems that the proposal by Hua et al. [45], modified by North [2a] (J, Scheme 6.4) best combines all the experimentally determined features. In this model, catalysis is effected by a diketopiperazine dimer and depends on the proton-relay properties of histidine (imidazole). R -OH represents the alcohol functionality of either a product cyanohydrin molecule or other hydroxylic components/additives. The close proximity of both R1-OH and the substrate aldehyde R2-CHO accounts for the stereochemical induction exerted by RfOH, and thus effects the asymmetric autocatalysis mentioned earlier. 

Package-Handling Systems The control of packagehandling systems may depend on simple motor starters, on interlocked relays with photocell control, or on computers. Solid-state controls are finding much application in the last two systems. 

Figure 1A is a schematic of the temperature measurement and control circuit. A type T thermocouple (see Note 2), inserted in a glass capillary, measures the temperature of a capillary with similar characteristics to capillaries holding the reaction mixture. The thermocouple is connected to an A/D channel of the data acquisition system (DAS) in a differential configuration (rrrNote 3). The DAS system is also used to communicate output commands (D/A channels) from the computer to the thermocycler. The DAS system employed in this study has eight channels available that can be used as either inputs or outputs. The fans and the heater are connected to the output channels of the board via solid state relays. 

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