Answer / raj

No.we cannot loop ac,dc neutral.because in unbalance condition some current flow with the neutral.ac and dc current shouldn't be mixed

Answer / s.r.nalawade

1.In AC circuit there is 'NEUTRAL' point where as in DC circuit the negative terminal is always connected to battery negative.
2. Consider example of Diesel generator. Battery is used for giving start command to starter motor through solenoid. Same battery is used for configuration of RUN/STOP command. Digital switching inputs like low oil pressure, high coolant temperature, remote start/stop are active low. i.e when battery negative is activated, generator controller will respond immediately.
3. Also there is main AC alternator coupled with engine. L1,L2,L3 & neutral are four terminals from alternator.
4. If AC neutral & DC negative is kept common, then unbalance neutral current will interfere with DC negative. Also, you will get line to neutral voltage (240V AC in case 3 phase 415V, 50 Hz system). Imagine the adverse effect of such a high potential on controller digital inputs. Also, as engine block, mounting skid & alternator body & battery negative terminal is interlinked, it will cause electrical shock to operator in contact with generator. Therefore AC neutral must be isolated from DC negative.

Answer / maddy

No, you cannot loop AC neutral wire with DC neutral wire.
Since AC current flows in both directions (forward and reverse), looping the AC with DC will make AC flow in the DC circuit. You dont want that to happen for a lot of reasons.

Answer / haarish choudhary

No,

Answer / makku

I don't believe this is up to code, but it will pass the test from a standard outlet tester. The problem I see is if any device plugged into the outlet comes into contact with a ground (e.g. water) and that path is more efficient than going all the way back on the neutral wire through the house wiring, then hot current going through any appliance and onto the neutral would come out the ground and possibly electrocute anyone in that path.

how the diesel generator maintain the rpm when the generator loaded varies from 10% to 70% immediately?

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2 Answers