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enter image description hereI have a grid tie inverter powered by a 24V battery connected to a circuit that is on a Generator. The grid tie inverter syncs well and outputs 655 – 800W according to the Load. As the load changes the Generator supply rises or falls accordingly.

There is a 30A charger in the design to top up the battery. The charger can be switched in or out.

An anomaly has me confused as follows:
When the charger is On (and the gauge shows 30A), the Load on the Generator should rise by 700W but does not.

What am I missing please?

J R_AU
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    Welcome to EE.SE. Adding a small schematic of your system can improve the question quality significantly. Good answer requires good question. You press on "edit" and edit your question to include the schematic. – Hazem May 25 '18 at 08:40
  • Yes, I agree thanks. Had started on it but lacked suitable drawing tool set. Will sort it out and add. – J R_AU May 25 '18 at 09:07
  • There is already an in-built tool. After you press on "edit", press Ctrl+M, a schematic tool will show up. – Hazem May 25 '18 at 09:27
  • Is the inverter running at the same time as the generator? If so it is probably drawing all the "charge" current. – Transistor May 25 '18 at 10:17
  • Hi Transistor. Thanks for the comment. There is a constant load of 2187w on the circuit for testing. It is supplied by the Generator, 1518W and the Inverter/Battery 669W. Yes, the inverter uses the Generator for its tie signal so both run together. And, yes the charge current goes to the inverter when the Charger is on which effectively 'removes' the battery as an energy source so the Generator output should increase ...? – J R_AU May 25 '18 at 10:30
  • I am confused why you want to do this. This is a system designed to create losses. There are losses through the charger, charging and discharging the battery, and through the inverter. Are you thinking the inverter will help stabilize the voltage by responding more quickly than the generator? – Rob B. Sep 10 '19 at 12:47

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The power to run your charger is coming from the inverter, not the generator. This is because the inverter produces a voltage a bit higher than the grid voltage (the generator in your case). This is so the inverter can provide power to the grid when the local load is sufficiently low. I can't see a way to force the charger to take its power only from the generator with your setup. My suggestion is: don't connect both the inverter and the charger simultaneously. Connect only the charger when the load is low and the battery needs charging. Connect only the inverter when you need to power a high load.

David S
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