Isolation switch is a low/high-voltage electrical appliance, plays an important role in the power system, it can play the role of isolating the power supply in the circuit, so as to protect the safety of equipment and personnel. The main feature of the isolation switch is that it has a high voltage and current carrying capacity, while ensuring the safety and reliability of the circuit. However, it is not always necessary to set the isolation switch. So, when do you need to set the isolation switch? Let's take a look.
01 What is the Isolation Switch?
1. The isolation switch is a disconnect no load current circuit, so that the maintenance equipment and power supply there is an obvious disconnect point, so as to ensure the personal safety of the maintenance personnel, the isolation switch does not have a special arc extinguishing device, so can not cut off the load current and short circuit current, so must be in the circuit breaker off the case can be isolated switch operation.
2. It usually in the power supply operation, first close the isolation switch, and then close the circuit breaker and load switch, power off operation, first disconnect the circuit breaker and load switch, and then disconnect the isolation switch.
3 In the selection of isolation switch and other electrical equipment, according to the product voltage, dynamic stable current and thermal stable current, etc., must meet the needs of the occasion.
02 How do I select the isolation switch?
1. The isolation appliance usually refers to the no-load current breaker, which can only break the no-load current, the isolation appliance has an obvious on-off display, such as the isolation switch, fuse, knife melt switch, plug socket connection piece, etc., can be used as the isolation appliance.
2. In order to better maintenance and testing and maintenance and safety needs, the isolation switch should meet the requirements of isolation, when the short circuit will also protect the appliance, can also be called the isolation appliance, the isolation switch should be installed near the control appliance.
3. The isolation switch must meet the circuit's rated voltage and through the calculation of current requirements, and according to the short-term and peak tolerance current verification. When the on-off capability is required, the on-off capability should be greater than the expected current of the loop.
4. When the isolation switch is used to install the isolation appliance, the center of the handle can not cut off the load current, and other forms of isolation switch can disconnect the corresponding load current, but a knife switch with fire arc cover must be selected.
