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🔌 MCB Size Calculator

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About the MCB Size Calculator

The MCB must suit the load and protect the wire. Get the rating, curve, poles and the minimum wire together.

How to use

  1. Enter the load and supply.
  2. Choose the type of load.
  3. See the MCB rating, curve and wire size.

Frequently asked questions

B, C or D curve?
B for lights and heaters, C for houses and small motors, D for big motors and welding.
Do I need an RCCB?
Yes — a 30 mA RCCB or RCBO protects people on sockets, bathrooms and geysers.

Free tool by Debnath Electronic, Khowai, Tripura. Works on phones and computers — nothing to install.

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