Emergency stop controls

Gas compressor anti-surge (GM-OFF) control circuit, comprising transmitters, computers and pneumatic control valve Reverse flow protection (on axnal compressors only) as supplementary protection device against surging, working independently of the control circuit Expander emergency stop valve with pneumatic actuator and solenoid valve... 

Stop, start, emergency stop and speed controls are grouped adjacent to the engine, and the machine is usually equipped with instrumentation for monitoring its safe operation. Very often, a centralized control room is provided, particularly when there are a number of units in operation. Typical signals monitored and recorded remotely are ... 

Red a. Stop buttons or electrical switches used for emergency stopping of machines. b. Emergency stop handles or bars on machines. c. Hazardous operation indicating lights on control, alarm panels, or in the installation. d. Fire protection equipment and systems (e g., fire hydrants, monitors, reels, alarms, etc.). e. Portable flammable liquid containers. f. Stop condition. g. Identification of ESD isolation valves and actuators. 

Unit Specification(s) Specific For each plant unit defines the unit type, phases, control modules, equipment modules. Hold and Emergency Stop states, interlocks, and transfer routes... 

Verify correct operation of process sequences during water simulations tune control loops. Ensure all process paths are tested, including any emergency stop and hold conditions. Verify correct operation of any recipe management and batch data recording during these tests. 

Should an emergency occur requiring immediate shutdown and over-ride of normal sequenhal shutdown, an EMERGENCY STOP pushbutton is provided for this purpose. This device interrupts power to all components in the oxidation unit control circuit, shuts down all motors, and closes the vacuum line valve and the chlorine pressure-reducing valve (PRV). The EMERGENCY STOP pushbutton is also used as a reset device to restore the system to normal operating status after an alarm situation has occurred. 

Know the location of Local start/stop switches Valves Controllers Control boards and panels Instrumentation Equipment Emergency stops Remote start/stop switches Safety equipment ... 

For example, the annex describes requirements for control devices (clearly visible, outside dangerous zones) and emergency stop devices. Work equipment presenting hazards due to emission of gases, vapors, liquids, or dust has to be fitted with containment or extraction devices near the source. 

Today, it is more and more evident that effective mitigation and control of corrosion phenomena requires the combined efforts of a team of experts that represents managment, conceptual and executive projects, research and laboratory testing, materials production, quality control, storage of materials, plant construction, controls and start-up, plant operation and corrosion monitoring, maintenance and emergency stops of a plant, and finally, plant decommissioning. 

The operators deliberately avoided tripping the reactor, as it had been in the earlier alternator tests, when the emergency stop valve to the turbine was shut to start the test. Automatic insertion of some control rods in fact commenced. 

The temperature control loop is equipped with temperature alarm TAl. Its signal is to prompt the operator to open the bypass of the temperature control, to stop the hexamine supply and to discharge the reactor contents by pushing an emergency button, which in addition activates the stirrer motor M2 of the emergency discharge tank. 

Stop controls should bring the equipment to a safe condition in a safe manner. Emergency stop controls are intended to effect a rapid response to potentially dangerous situations and should be easily reached and activated. Common types are mushroom-headed buttons (see Fig. 1.5), bars, levers, kick plates or pressure-sensitive cables. 

The machine can be stopped by returning the spindle-control lever (18) to its central stop position. Alternatively, press the emergency-stop push button (8) or depress the full-length foot brake pedal (22). 

B1 Standards. These apply to particular aspects, such as surface temperatures and safety distances. Some B1 examples are EN 418 (Emergency Stop Systems), EN 954-1 (Safety Related Control Systems), and EN 60204-1 (Electrical Requirements of Machinery). 

The emergency stop can be actuated manually by a pushbutton (two different electrical contacts) on the remote control (transmitter) during the flight phase. In the event of loss of radio-frequency communication, an emergency stop order is generated by a microcontroller located on the top of the bell and independent of the control system. 

The emergency stop must be transmitted and conducted according to two distinct processes controlled by two different mechanisms on each entity (transmitter and receiver). 

An operator control, usually a push-button with a large, red, protruding mushroom head, that when actuated initiates an emergency stop. 

Arrest of dangerous machine motion resnlting from actuation of an emergency stop switch. The switch may be in the form of a safety switch, bntton, trip cable, or foot bar or other mechanical device used in conjnnction with an emergency stop safety module. Emission Control... 

Control bed rail—A bed rail that incorporates bed function controls for patient/staff activation. Control device—Any control hardware providing a means for human intervention in the control of a robot or robot system, such as an emergency-stop button, a start button, or a selector switch. Controlling—Measuring performance of work by monitoring outcomes. 

Device—Any control hardware such as an emergency-stop button, selector switch, control pendant, relay, solenoid valve, or sensor. 

Emergency situation—Any occurrence including equipment failure, rupture of containers, or failure of control equipment that results in an uncontrolled substantial release of a contaminant. Emergency stop— The operation of a circuit using hardware-based components that overrides all... 

Some machines use a pressure-sensitive body bar, safety trip rod or trip wire, cable, or cord. Requiring a worker to reach over a pressure-sensitive body bar to perform some function near a point-of-operation will allow any excessive leaning to trip the control and stop the machine. Pushing or pulling on a trip rod or trip wire will also stop machines in an emergency. 

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