415VAC 3 Phase to 240Vac Single Phase

This is the CNC machine basic wiring diagram to step down the 415 VAC 3 phase power line to 240VAC single phase. To step down the 415 VAC 3 phase to 240 VAC 1 phase, I will take the L1 and N and connect them to 2 poles Miniature Circuit Breaker (MCB). The combination of L1 and N will generate 240 VAC single phase power line.


415 VAC to 240 VAC Step Down Circuit Diagram

L1 = R = Life 1
L2 = S = Life 2
L3 = T = Life 3
N = Neutral
E = earth or grounding

In the CNC machine, the 415 VAC 3 phase normally use by the CNC machine spindle motor. In fact, most CNC machine spindle motor can use whether 415 VAC 3 phase or 220 VAC 3 phase. The use of 240 VAC single phase is very seldom in CNC machine however some CNC machine retrofitter will use this power line to retrofit the CNC machine especially to power up the lamp and lubrication system but mostly depends on the industrial electrical components standard input power of each country or state.

When building a CNC machine, Earth Leakage Circuit Breaker (ELCB) and MCB must be used to ensure all the CNC electrical and electronic components are well protected. For extra protection, fuses are also will be used. I myself use ELCB range from 40 Amp to 80 Amp, MCB range from 20 Amp to 32 Amp and fuses range from 10 Amp to 20 Amp.