Electrical networks typically power several machines simultaneously. It is essential that each of these machines can be switched off individually. This can be achieved by installing a switch disconnector in the electrical network.
What is the role of a fuse switch disconnector?
A fuse switch disconnector is an electrical protection device that can manually open or close a circuit, allowing a technician to isolate electrical power supply circuits from the network.
The fuse switch serves two functions:
- The isolation function, performed by the switch
- The additional fuse protection function, which is often incorporated. This function protects the power supply line against overloads and short circuits.
Please note that it is important to understand that the device must always be operated under no-load conditions, as it does not have a load-breaking capability.
What are the different functions of a disconnector?
The main contacts:
- The main contacts ensure that the machine is isolated from the network, which is mandatory before carrying out any maintenance work.
The auxiliary contacts or poles:
- The auxiliary contacts or pre-breaking poles isolate the control circuit before the power circuits are disconnected.
How to choose a disconnector?
Several steps are necessary to make the right choice:
- Determine the number of poles. They can be of different configurations:
- Single-pole + neutral
- Double-pole
- Triple-pole (three-pole)
- Four-pole - Determine the operating voltage
- Determine the maximum current that the device can withstand for a limited time
- Choose the type of fuses
- Determine the number of auxiliary contacts
- Choose the accessories:
- The type of control: the mechanism used to operate the device (handle on the left, right, front-mounted, remote operation, etc.)
- The mounting system: the method of mounting the device
- The locking device
