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Why CT (Current Transformer) Direction Matters

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 I have seen a lot of comments on Youtube videos and in forums that the direction of CT's don't matter as the current is reversing at 50Hz or 60Hz. This is fine assumption if you are just looking at the current waveform. This is a 12.6A current waveform from a 30A/1V CT. As you can tell the waveform goes back and forth as you would expect. Here is a look at the same waveform but in the context of the 120V AC sine wave and as you can see the current (blue) goes up as the voltage (red) goes up. This is with a purely resistive load. This is the same waveforms but with the CT reversed and as you can see here the current goes up as the voltage goes down. If you synchronize your voltage and current waveforms (I.E take the measurements at the exact same time) you can then see if the signals are in phase which each other or out of phase by 180 degrees. If they are in phase then the current is following one direction if they are out of phase then current is flowing in the opposite direc
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Victron : Disconnect Inverter from Grid using AUX1

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This is also known as Islanding or Ignore AC I see this come out quite often on the forums where someone would like to disconnect from grid for some reason, this could because they have grid stability issues or they have a prepare meter and have issues of it tripping. You can use the Cerbo to disconnect the inverter from grid at certain battery SOC and reconnect later using the generator menu. If you are using NodeRed please note that you do not need to do this. You can just set the inverter switch position to Inverter Only to disconnect from Grid and On to rejoin. Back to using AUX1. Wiring is pretty simple. If you connect the AUX1 + to the - that means closed and will cause the system to disconnect from grid if you do everything below. STEP 1, Open VE.Config and connect to your inverter. STEP 2, Disable Virtual Switch, this is already the case if you are using an Assistants like ESS. STEP 3, Add General Flag Assistant and set to ignore AC input 1 or the input you would like to disco
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Micro Grid -

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 This post is going to be about how I deployed a micro grid base on Victron inverters. This will include what I did as well as all the problems I discovered. Let's talk about how the system is laid out.  The house has its own full Victron setup. Victron Multiplus-II 48/5000/70-50 Victron SmartSolar Charger MPPT 150/60 Victron SmartSolar Charger MPPT 150/35 Victron Cerbo GX Victron CT for Multiplus Freedomwon 10/8 Lite Battery This system is the Master and is the grid forming inverter, it also handles connecting and disconnecting from grid in the case of an outage or if we want to isolate for any reason. The Garage has 2 systems on it. The first is a victron system that consists of: Victron Multiplus-II 48/5000/70-50 Victron  SmartSolar MPPT RS 450/100 Victron Cerbo GX Freedomwon 10/8 Lite Battery The second is an Enphase system: Enphase Envoy-S Metered 5x Enphase IQ7 Micro Inverters The control system for this microgrid is split across the two GX's which are both running the la
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