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IEC 60364 Table 48A

Former Community Member over 3 years ago

Does anyone know where I can find table 48A? I am reading of its existence, but don't know where to find it.

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0 wallywombat over 3 years ago

ProMbrooke:in circuits 32 amps and below 99% of the VD during a fault is on the circuit itself and not the supply between the transformer and consumer unit.

Huh? Let's take some typical order-of-magnitude values for a suburban house. Ze might be around 0.2 Ohm, while R1+R2 for a radial socket might be about 0.4 Ohm. A short at/near the socket will result in about 2/3 of the VD in the circuit itself. For it to be 99%, R1+R2 would have to be around 20 Ohm.
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0 wallywombat over 3 years ago

ProMbrooke:in circuits 32 amps and below 99% of the VD during a fault is on the circuit itself and not the supply between the transformer and consumer unit.

Huh? Let's take some typical order-of-magnitude values for a suburban house. Ze might be around 0.2 Ohm, while R1+R2 for a radial socket might be about 0.4 Ohm. A short at/near the socket will result in about 2/3 of the VD in the circuit itself. For it to be 99%, R1+R2 would have to be around 20 Ohm.
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IEC 60364 Table 48A

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