Idle 'no load' Consumption: Specs vs Personal Observation

Dzl

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In this thread, I hope to consolidate personal observations/measurements on inverter standby consumption. Specifically whether your observations are inline with what is stated on the datasheet, along with anything else you consider relevant, interesting, good or bad. With time--if this thread gains traction--it could be a useful resource for those shopping for inverters, and help us calibrate our expectations.

At a minimum report (1) Make+Model (2) Voltage (3) Max continuous power (4) Observed/measured standby consumption compared to spec sheet (5) Indicate whether power save features are active or not

*Keep in mind, any individual datapoint (even when its your own experience) is just a datapoint, subject to measurement error, bias, etc, but with a handful of datapoints, we can begin to feel a bit more confident drawing conclusions/generalizations.
 
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eXodus

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(4) Observed/measured standby consumption compared to spec sheet (5) Indicate whether power save features are active or not
My Growatt 24V takes a lot of power while standby from the Grid/Generator, but less when running from battery/Solar panels.
What value are you looking for?

You might define that more narrow: Standby consumption, nighttime, from batteries. Further, my growatt is not showing the self consumption on the display.

1. growatt spf 3000tl lvm-24p
2. 120V
3. 3000W
4. 58W from Grid (Kill a watt), 1.6A @ 27V 42W From battery (no specification to be found)
5. Power Saving: 8-15W from Grid, toggles up and down, not readable with my Clamp on meter
 
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Steve_S

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MurphyGuy

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2x SMA Sunny Island's (48 volt)@ 6kW each, (12kW total) -120/240 split phase.

Standby 4 watts each (8 watts total) (Exactly on spec)
Active but with No Load 24watts each (48 watts total) (2 watts lower than specs)

Both of these measurements include the BMS draw and the Main Contactor coil with a combined draw of probably 1 or 2 watts.
 
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corn18

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  1. Victron Multiplus II
  2. 120V
  3. 3000VA
  4. 20W (20W spec)
  5. Search mode is 8W
 
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andyP

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What a helpful thread.
Unbranded PSW inverter from ebay.
Rated 2500w, 220v
No load draw at 12v is 2-3amps
No power save option.
 
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Bob142

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  1. Victron Phoenix VE.Direct
  2. 24V DC / 120V AC
  3. 1200VA, 1000W
  4. 13W (8W spec)
  5. With power save feature ON: 3W (spec 2.3W)
 
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Dzl

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13W (8W spec)
13W for an inverter rated for 8W is a pretty significant difference (only 5W over in absolute terms but that is like 60% over spec) I wonder if your measurement is representative of the smaller Phoenix inverters or an outlier.
 

Bob142

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13W for an inverter rated for 8W is a pretty significant difference (only 5W over in absolute terms but that is like 60% over spec) I wonder if your measurement is representative of the smaller Phoenix inverters or an outlier.
I agree - I was surprised. I've got a 12V 1200VA Phoenix non-VE.Direct inverter I'm integrating into a new build. I'll report back when I have that measured.
 
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offgriddave

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(1) Make+Model (2) Voltage (3) Max continuous power (4) Observed/measured standby consumption compared to spec sheet (5) Indicate whether power save features are active or not
1. Victron 48/375VA 700w
2. 48volt 750wh batteries Lithium Ion Ebike batteries, 40-52v. 120v inverter
4. Standby measured .25 amp at 47.74v or 12w. Spec sheet: 9w. Measured with AMES Clamp on CM1000A
5. No power save feature enabled aka "eco mode". I'll give it a try tomorrow
 

Tecnodave

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All inverters 24 volt, published specs listed......<as tested in use here>

MagnaSine MS4024AE 4kw 120/240 low frequency iron core transformer 20 watts idle <32 watts...fans locked on>

Exeltech XP 1100-124 1100 watts 120 v high frequency ultra clean sine wave very low EMI/RFI 20 watts <20 watts>

Exeltech XP 600-124 600 watts 120 v high frequency ultra clean sine wave very low EMI/RFI 8 watts <8 watts>

Dynamote Brutus 3200 watt 120v. low frequency iron core transformer 96 watts <88 watts>

Brutus is an antique (1984-86??) being the very first high frequency electronics driving a low frequency transformer inverter ever made
whopping overload 11,900 watts 180 secs. will drive high starting power loads that much bigger inverters will not drive
 
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SpongeboB Sinewave

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The Brutus was first designed and built in Seattle and the engineers for the Brutus ended up working at Trace Engineering in the late nineties just before Xantrex merger...

Dynamote had some kind of small-ish inverter circuit they used for reducing idle power. Can't remember much about it but there was a patent they had for that.

If this 88 watts was while using this low idle circuit, it probably didn't work as well as I had thought it would.

boB
 

Tecnodave

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The Brutus was first designed and built in Seattle and the engineers for the Brutus ended up working at Trace Engineering in the late nineties just before Xantrex merger...

Dynamote had some kind of small-ish inverter circuit they used for reducing idle power. Can't remember much about it but there was a patent they had for that.

If this 88 watts was while using this low idle circuit, it probably didn't work as well as I had thought it would.

boB
CORRECTION......


Some Dynamote inverters had a small 70 watt inverter that worked at small loads and then switched to the full inverter.

The Brutus was the first Static Dynamote inverter and did not have the 70 watt “starter inverter” but some later models did have the starter inverter built within the big inverter, Those models had a very modest idle current, but did come later than the Brutus. Cant remember exactly but 10 watts or so of idle.....

Dynamote,s biggest product was their “DYNAMIC INVERTERS” These did not run on a battery but used the Leese-Neville 3 phase alternator in the fire trucks and ambulances that they were designed to be used with. The alternator was controlled by the inverter and produced about 30-40 volts AC phase to phase and this power was rectified within the inverter which provided up tp 100 amps at 12 system voltages PLUS up to 6 kw of 120 volt 60 cycle power.

When the inverter was shut off it still controlled the alternator which then provided the 12 volt system of the fire truck.
 

SpongeboB Sinewave

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CORRECTION......


Some Dynamote inverters had a small 70 watt inverter that worked at small loads and then switched to the full inverter.

The Brutus was the first Static Dynamote inverter and did not have the 70 watt “starter inverter” but some later models did have the starter inverter built within the big inverter,

Dynamote,s biggest product was their “DYNAMIC INVERTERS” These did not run on a battery but used the Leese-Neville 3 phase alternator in the fire trucks and ambulances that they were designed to be used with. The alternator was controlled by the inverter and produced about 30-40 volts AC phase to phase and this power was rectified within the inverter which provided up tp 100 amps at 12 system voltages PLUS up to 6 kw of 120 volt 60 cycle power.

When the inverter was shut off it still controlled the alternator which then provided the 12 volt system of the fire truck.

Yes, the 70 watt inverter. A Co-Inverter I think Milt Rice called it.

Here is their old patent. And it was Vanner bought Dynamote which I had forgotten their name.

 
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OffGridInTheCity

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I run 2 x AIMS 12,000w (48v) inverters. Each one can supply 240v@50a.

The manual says 200w idle consumption in the mode most commonly used and the mode I use....
1638652749704.png

However, I focus on overall efficiency rather than just idle load - even though I suspect they are related. Here's the specs for efficiency:
1638652916429.png

I have discovered thru use/metrics that you as you get toward 40% load (4000-5000w) the efficiency approaches 85%. If you load it lightly, efficiency quickly drops into the 70(s). Note: I'm off-grid, don't have any grid coming into the inverters.

I have 2 of these and have wired the 2 distribution panels so that I can run both AIMS in summer when I have lots of power but only 1 in winter. The difference is *stark*. In 2020 the Inverters ran for 5,493 hours with an average load of 3,046watts/hour. At peek, they achieved as much as 85.8% (single AIMS) but it has been as low as 78.5% with both running in spring.

The 2020 yearly average with manual intervention was 83.6% efficient. To give you context - the PV array produces 18,000kwh/year but I'm only getting 15,000kwh out of the inverters. That's 3,000kwh/year I'm loosing!!!

Bottom line - its not just 'idle' but overall operational efficiency that's important to me. I wish I'd gone with MagnaSine or something more efficient! But functionally, the AIMS work flawlessly.
 
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Tecnodave

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I run 2 x AIMS 12,000w (48v) inverters. Each one can supply 240v@50a.

The manual says 200w idle consumption in the mode most commonly used and the mode I use....
View attachment 74526

However, I focus on overall efficiency rather than just idle load - even though I suspect they are related. Here's the specs for efficiency:
View attachment 74527

I have discovered thru use/metrics that you as you get toward 40% load (4000-5000w) the efficiency approaches 85%. If you load it lightly, efficiency quickly drops into the 70(s).

I have 2 of these and have wired the 2 distribution panels so that I can run both AIMS in summer when I have lots of power but only 1 in winter. The difference is *stark*. In 2020 the Inverters ran for 5,493 hours with an average load of 3,046watts/hour. At peek, they achieved as much as 85.8% (single AIMS) but it has been as low as 78.5% with both running in spring.

The 2020 yearly average with manual intervention was 83.6% efficient. To give you context - the PV array produces 18,000kwh/year but I'm only getting 15,000kwh out of the inverters. That's 3,000kwh/year I'm loosing!!!

Bottom line - its not just 'idle' but overall operational efficiency that's important to me. I wish I'd gone with MagnaSine or something more efficient! But functionally, the AIMS work flawlessly.
@OffGridInTheCity

I have seen those AIMS inverters, huge idle draw, I measured it at 200 watts idling...The low frequency inverters have a larger idle draw than most high frequency inverters. The one standout is the Samlex EVO 4024 which is less than 20 watts but that is evolution. Samlex has obviously upped the ball with the EVO
 

Dzl

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I run 2 x AIMS 12,000w (48v) inverters. Each one can supply 240v@50a.

The manual says 200w idle consumption in the mode most commonly used and the mode I use....
View attachment 74526

However, I focus on overall efficiency rather than just idle load - even though I suspect they are related. Here's the specs for efficiency:
Bottom line - its not just 'idle' but overall operational efficiency that's important to me.
In my eyes both are important in different contexts. This post was focused on gathering user reports on idle consumption/standby specifically (though I am interested in both, so I appreciate your data), conversion efficiency matters as much ore more in some scenarios.

Its pretty cool that you've gathered/kept detailed data on conversion efficiency. How are you measuring/tracking this?
 

Dzl

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@OffGridInTheCity

I have seen those AIMS inverters, huge idle draw, I measured it at 200 watts idling...The low frequency inverters have a larger idle draw than most high frequency inverters. The one standout is the Samlex EVO 4024 which is less than 20 watts but that is evolution. Samlex has obviously upped the ball with the EVO
Victron Multiplus-II has notably low idle consumption as well, if the specs are accurate. 3000VA, 48V idle of just 13W, 93% efficiency. Only 12V and 48V available in the US so far I think, no 24V models yet, but the specs from the 5000VA 24V European model show 18W, 96% peak efficiency
 
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