1. The switch function
Function switch disconnect and reconnect the electrical circuit. The higher voltage systems which are connected and disconnected to the system, the more difficult process of facing disconnection of electric circuits because the higher the voltage, the higher the voltage transient at the time of disconnection in the circuit. Voltage transients can bring back the electric current has been disconnected.
Construction of the switch should take into account the nature of the circuit, the capacitive electrical circuit is disconnected, the greater the re-ignition due to capacitive circuit has the ability to store a large electrical charge and can be raised again when the circuit is disconnected.
At the time of the electrical circuit is disconnected, the switch contacts arise arcs. Electric arc causes the switch contact material is oxidized so hantarnya reduced power when the switch contacts close again. To reduce the effect of oxidation, motion switch contacts must be clean itself.
2. Switch type
The switch for the purposes of electrical circuits with voltages above 1.5
kV can be divided into 3 types, namely:
a. Switch the circuit breaker (PMT)
Circuit breaker (PMT) is a switch that is able to break the short circuit fault current circuit breaker switch is in English called a circuit breaker (CB).
b. Load breaker (PMB)
Load breaker or load break switch (LBS), is a switch that is only able to break the flow of load current.
c. Separator (PMS).
Separating or insulating (disconnecting) switches. Separator (PMS) should only be operated with no flow. The position of the knives should be viewed PMS. real position, either closed or open, for safety purposes.
In practice, a PMT combined with three PMS as shown in Figure II.35, the PMS two each at the front and at the back of the PMT, and a PMS that is used to ground the installation part to be exempt from the voltage that can be touched by humans for implementation of repair or maintenance work.
