Handling of signal equipment accident signs or some abnormal conditions
Closed or open relay; intermediate relay: a relay used to increase the number of signals or amplify the signal; signal relay: a relay used to send signals or act on the signal system display.
In the control auxiliary circuit, in addition to the relay, the protection circuit is indispensable for the control switch. Its function is mainly used to turn on and off the main switch, such as control buttons, switches, universal switches LW5, LW12, etc. In addition to the above control protection components, there are also electricians Meters, indicating meters, recording meters, and accumulating meters need to be equipped with frequency meters for generators.
Indicators include: current, voltage, power, phase, etc.
Recording instrument: an instrument used to record electricity or convert non-electricity to electricity after transformation. The recording methods include transcript type, dot type, accumulative meter and watt-hour meter.
Signal equipment: The types are generally divided into normal operation display equipment, signal equipment, accident signal equipment, and command signal equipment. Signal devices for normal operation are generally signal lights of different colors. The light sign is often used for power supply indication, and has on and off position indication, equipment running and stop status. The accident signal equipment includes accident warning signal equipment and accident signal equipment. The accident signal is also called the central signal in some cases. When the electrical equipment or system has some signs of accident or some abnormal conditions, such as poor insulation and neutral point is not grounded. In a three-phase system, one-phase ground fault, light overload, and equipment temperature increase, but the signal that has not caused the seriousness of the equipment or system not being able to operate immediately is called the accident warning signal system. When the equipment or system failure has occurred The signal issued by the automatic switch has tripped is an accident signal. The accident warning signal and the accident signal are generally composed of light signals and sound signals. The sound signals can call the attention of the duty or the operator, and the light signals can indicate the type, nature, and occurrence of the accident. Location, etc. The accident signal and the pre-announcement signal can use different sound signal devices, such as the buzzer, electric whistle, electric horn, etc., and the electric bell.