AC Loads being reported erroneously in VRM Dashboard/Remote Console

I only have one 75W light bulb hooked up to a 48|1200VA Phoenix inverter. VRM dashboard AC out is reporting a whopping 252W AC load. It also shows discharging only 94W which seems fairly accurate considering the efficiency of the Phoenix.

Although I have no DC loads I've got 'has DC system' active trying to troubleshoot this issue.

Remote console is also reporting a very similar draw:

I have disabled DVCC but that made no difference and have since reenabled it.

I've experienced similar issues with my Quattro and believe I chocked it up to an inefficiency. I feel like this being such a small inverter though.. the AC loads should be a lot closer to the actual 75W rather than this. Any ideas? @snoobler?

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snoobler commented · Dec 29, 2023 at 03:53 AM

I have no explanation.

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Alexandra ♦ commented · Dec 29, 2023 at 04:47 AM

Does the accuracy it improve with higher loads? If it does then it is the measurement method in the phoenix. If I recall from somewhere here the hall effect sensors under 4 or. 5 Amps are not accurate.

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JohnC ♦ commented · Dec 29, 2023 at 06:02 AM

Also, Remote Console is reporting in VA, not W. I don't think VRM can handle VA, it treats it as W.

The A is reported to round figures too, not the normal 1 dp. Suggesting that it's been told to do that, perhaps because of the known inherent inaccuracies already suggested.

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northtown2022 commented · Feb 05 at 01:43 AM

Finally got around to building a 1200W test light and did some testing. I think what @Alexandra suggested regarding inaccuracies of the hall effect sensor at lower amperages is in fact the case. Oddly enough the JK BMS I'm using seems to be the winner, and for the most part the smart shunt agrees. I'd like to see more accuracy but I suppose for the Phoenix it's likely more about keeping the cost in perspective.

300W:

600W:

900W:

1200W:

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Alexandra ♦ northtown2022 commented · Feb 05 at 10:58 AM

For most systems the battery is always the main concern and the one providing power. and pretty much the heart of the system.

Anyone really serious about power usually use the battery reading anyway. It is the purest form of VA. with no bad sine wave weird loads or rms to mess it up.

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