Adiabatic Equation Calculator

The Adiabatic Equation for calculating the cpc (circuit protective conductor) and earth minimum csa sizes for earthing conductors. Adiabatic Equation Calculator Formula t = Disconnection time (seconds) k = Conductor k value (From BS 7671 tables) la = Fault current (PEFC in Amps) I² = la x la Values of K obtained from the tables within BS 7671 - Table 54.2 : Conductor not incorporated in a cable and not bunched with cables. - Table 54.3 : Conductor incorporated in a cable or bunched with cables. - Table 54.4 : Sheath or armour of a cable. - Table 54.5 : Steel conduit or trunking. Disconnection times (t) are obtained from the maximum operating time/current characteristics tables within BS 7671 - Fig 3A2 (a,b) : BS 3036 semi-enclosed fuse - Fig 3A3 : (a,b) : BS 88-2.2 - Fig 3A4 : BS EN 60898 / 61009-1 MCB/RCBO type B - Fig 3A5 : BS EN 60898 / 61009-1 MCB/RCBO type C - Fig 3A6 : BS EN 60898 / 61009-1 MCB/RCBO type D - BS 1361 Fuse How to use the Adiabatic Equation 1) Input your voltage value 2) Input your Zs/Ze/Zdb value 3) Select a protective device 4) Select a protective device rating 5) Select a conductor type 6) Select a conductor material 7) Press calculate Check out our full collection of electrical apps for Android in the Play Store.