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  • #46
    Originally posted by Sunking View Post
    Not so sure your meter does not require a ground though. Unless it is Double insulated, UL, with a Polarized plug, it is required to have a Equipment Ground Conductor.
    Mine is not UL listed, although there is one that is identical that costs xx% more that carries the mark. Neither requires (or accepts) a ground. The case is 100% plastic, no exposed metal, no reason to require an EGC as far as I (and UL) can see. There is no plug, just touch-safe terminals for each of the voltage inputs.
    CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

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    • #47
      Originally posted by Sunking View Post
      Tell me please. I would like to know.
      Current UL listing requirement for anti-islanding. Too high a differential between the two line to neutral voltages must disable the GTI.
      This causes some interesting problems (discussed on MH, if I recall correctly) when the circuit was pulled as 240 without neutral.
      SunnyBoy 3000 US, 18 BP Solar 175B panels.

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      • #48
        Originally posted by Sunking View Post
        How so? It cost more to add a Neutral circuit requiring current and a fourth terminal costing the manufacture more money, and the consumer having to add the 4th wire.

        It is still more complicated adding the additional circuit requirements to pick off 120 volts when 240 is already there.
        120 *AND* 240 are already there.
        The 120 is already required for anti-islanding, so there isn't an additional cost for the neutral because the neutral terminal (and wire) already have to be there for that purpose.

        It is quite possible it uses 240 - But my guess would be the 1 or 2 watts it uses is from the 120V.
        I think the power supply would be closer to the psuedo-wall-warts for charging your phone than a laptop brick. (much smaller power output requirement, don't need to handle the variety of inputs, and standby (nighttime) power is more important)

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        • #49
          Originally posted by inetdog View Post
          Current UL listing requirement for anti-islanding. Too high a differential between
          the two line to neutral voltages must disable the GTI. This causes some interesting problems (discussed
          on MH, if I recall correctly) when the circuit was pulled as 240 without neutral.
          That is the case here, the (adjustable) 120V monitor works against the neutral. But the neutral
          carries no inverter load current, downsized quite a bit from load wiring. Bruce Roe

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          • #50
            Originally posted by bcroe View Post
            But the neutral carries no inverter load current, downsized quite a bit from load wiring. Bruce Roe
            That is exactly what is bothering me Bruce. No load current means it is a ground. Only difference in that case is the insulation color. Neutral conductors carry load load current, ground conductors do not. That makes it a a 0 Volt Cross Over Ground Reference Point. It wil see any unbalance between L-N without any error induced by voltage loss with current running through it.
            MSEE, PE

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            • #51
              Originally posted by inetdog View Post
              Current UL listing requirement for anti-islanding. Too high a differential between the two line to neutral voltages must disable the GTI.
              I understand that.


              Originally posted by inetdog View Post
              This causes some interesting problems (discussed on MH, if I recall correctly) when the circuit was pulled as 240 without neutral.
              Thx, that is where i should have asked in the first place. I will ask Charlie B, Mike H, John W, and Iwire.
              MSEE, PE

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              • #52
                Originally posted by SunEagle View Post
                The inverter that is being used by the OP is a Solectria 7600TL. According to the installation manual you are required to bring in the Neutral wire from your main power panel and terminate it to the Inverter N or neutral terminal.

                The question is why does this inverter require the neutral wire?

                --Mod Note: When your first post is diverted to moderation, posting again will not help.
                Meanwhile your question about why the inverter requires a neutral has been answered.
                LOL. I thought my first post got lost when it didn't show up so I repeated it. I have to pay more attention to the pop up messages after posting.

                Thanks for clearing up the Neutral wire question for that inverter.

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                • #53
                  It might be off topic at this point, but I reconfigured my meter to pick up the inverter conumption more accurately. Solar production stopped at about 7:31:00 pm here this evening.

                  From then until 7:47:15 (sampling every 5 sec), I picked up about 2 W on each leg, or ~4 W total.

                  More precisely, it generates 1600 pulses / kWh.... during this time it ticked one full pulse in 0.144 hours, indicating 4.3 W.

                  Whatever the draw is once it fully goes into shutdown mode overnight is less than this, and not detectable with the configuration I'm using. The fact that this low wattage consumption is ocuring at 240 V would lead me to believe that all low power consumption is at 240 V, and there is not any 120 V draw.

                  Edit: SolarEdge data sheet says nighttime power consumption is < 2.5 W. I guess it would take a few more wraps through the CT to detect that.
                  CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

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