How to choose your distribution block according to your installation?

What is it for?

• Correctly dimension the distribution blocks.
• To prevent equipment from deteriorating (breakage, melting, etc.) or melting in the event of a fault.
• Ensure the safety of persons and electrical installations.

How to select the right product?

To select the right product for the installation’s ICC, two main electrical characteristics must be taken into account:

• Ipk (peak current): represents the maximum instantaneous current that can occur at the very beginning of a short circuit. Ipk is important because it determines the mechanical resistance that a device must withstand without breaking. This current corresponds to the maximum current that can be carried by the modular distributor over a period of 0.1 seconds (according to standard 60947-1). It is expressed in kiloamperes (kA).
• Icw : is the permissible short-circuit current. It is the short-circuit current that a device can withstand for a given period of time without suffering permanent damage. This current corresponds to the square root of the current value over a period of 1 second (according to standard 60947-1). It is also expressed in kiloamperes (kA).

We can also use this Icw to compare it to the Icc3 commonly used by certain manufacturers or in calculation software. The Icc3 corresponds to the short-circuit current in a three-phase fault. The “3” in Icc3 refers to the three phases. Icc3 is the most severe type of fault (three phases short-circuited together), compared to a phase-to-neutral or phase-to-earth fault. It is important that the Icw is
greater than the Icc3.
For these various reasons, Icc3 is often used as the main reference in short-circuit calculations.