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Thread: E Loop and inverters

  1. #11
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    Another case, did the E loop and the N loop of a Victron.

    E loop of 4.6ohms
    N loop of 4.6 ohms.

    This means the resistance of the earth wire was the same as the Neautral thus the same readings.

    This gives a fault current of 49.3 Amps (the voltage was 227on the rest instrument)

    So now that means the output CB needs to be at minimum a 25Amp CB to satisfy the double the current thing as that allows instant trip. (Depending on the type or curve of the breaker).

    But the AC passthrough is 70Amps! So putting a 25A main CB basically renders the inverter useless.

    So now what happens when it comes to the CoC when we test the inverter supply ?

    Sent from my CPH2197 using Tapatalk

  2. #12
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    Not sure why the meter read 227volts as it is set to 230 output in island mode though. Maybe my meter is weird as often reads different to my other multimeter too

    Sent from my CPH2197 using Tapatalk

  3. #13
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    I am not sure but, since it is not practical, as the reg states, it looks like reg 8.6.5.2 must be applied then? Since it is the only "other" alternative without dropping the breaker size.

  4. #14
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    Me too but that to me is neutral loop test. Also inverters have their own inbuilt protection so surely doing a CB for the conductor protection is satisfactory?

    Sent from my CPH2197 using Tapatalk

  5. #15
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    Quote Originally Posted by Dylboy View Post
    Not sure why the meter read 227volts as it is set to 230 output in island mode though. Maybe my meter is weird as often reads different to my other multimeter too

    Sent from my CPH2197 using Tapatalk
    If the meter is not true RMS it can struggle to read a modified sine wave and you may find that the sine wave is a bit out -

  6. #16
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    Quote Originally Posted by Dylboy View Post
    Another case, did the E loop and the N loop of a Victron.

    E loop of 4.6ohms
    N loop of 4.6 ohms.

    This means the resistance of the earth wire was the same as the Neautral thus the same readings.
    In my opinion the meter has done a N loop on both readings which is why you are getting the same reading.

    The earth loop should be zero as you are right at the earth neutral point.

  7. #17
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    Quote Originally Posted by Dylboy View Post
    Another case, did the E loop and the N loop of a Victron.

    E loop of 4.6ohms
    N loop of 4.6 ohms.

    This means the resistance of the earth wire was the same as the Neautral thus the same readings.

    This gives a fault current of 49.3 Amps (the voltage was 227on the rest instrument)

    So now that means the output CB needs to be at minimum a 25Amp CB to satisfy the double the current thing as that allows instant trip. (Depending on the type or curve of the breaker).

    But the AC passthrough is 70Amps! So putting a 25A main CB basically renders the inverter useless.

    So now what happens when it comes to the CoC when we test the inverter supply ?

    Sent from my CPH2197 using Tapatalk
    Are you a over night solar installer or a qualified electrician why not see if you can fix the problem?

  8. #18
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    Quote Originally Posted by Die sparky View Post
    Are you a over night solar installer or a qualified electrician why not see if you can fix the problem?
    You may think you are " Die Sparky " but for a first post without knowing the guys and value that they bring to this forum , I think you have overstep the mark.

    If you have no value to add , rather keep quite , otherwise please explain the reason that both readings would be the same

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  10. #19
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    Quote Originally Posted by GCE View Post
    You may think you are " Die Sparky " but for a first post without knowing the guys and value that they bring to this forum , I think you have overstep the mark.

    If you have no value to add , rather keep quite , otherwise please explain the reason that both readings would be the same
    Both readings should be the same or very close because you are testing the loop either via the neutral or via the earth but they should be much lower. Posible cause for high readings i dont think has to do with electronics i believe there has to be a neutral earth bonding relay/contactor so mabe loose connections or bad contacts.

  11. #20
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    The AC passthrough is 70 amps but can the inverter deliver 70 amps in island mode? Would have to be one hell of a inverter so perhaps 4.6 ohm is correct for the inverter?

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