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Anybody measure the standby idle loss on their Phocos 5kw inverters?

Maast

Compulsive Tinkerer
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Location
Washington State
I'm considering one for a smallish off-grid project and since idle loss is a great first-pass indicator of the quality of the unit I'd like to know. They claim 40W but I'd like to know what it really is. MPPs idle loss claims are far less than their actual 74W idle usage.
 
You have a link to Phocos?
40 watt is not realistic for 5kw unit.

Even the best high quality components should give atleast 100 watt.

Usually between 2 and Up to 5% of rated capacity.

There is a "trick" they like to use..
Sleeping Modus.
So not providing power, standby.
And with a power draw above 50 watt or so it wakes up.

Not realistic as you want to use the inverter :)

If you use 100 watt, expect minimal 200 consumption.
Efficiency 85-90%, 225 watt battery drain.
For 2000 watt..(+the 100)
2350W battery drain.

You get the idea.
And probably already know as you like to know their real power consumption.

The seller should be able to provide real information.
Or you can extract out of the information provided.

If I use 500 watt, AC, how much is the battery drained?

If I use 2500 watt, AC, how much is the battery drained?

If I use 4500 watt, AC, how much is the battery drained?
(Please show shunt/am meter with drain information.

Information they should be able to provide
 
fhorst

Not sure where you get your numbers.

40W for 5kW is realistic unless you're buying cheap.

My Victron 5kW uses 30W idle verified. "Sleep" mode is always disabled as I always have a load.

5% of rated is flat out absurd unless you're talking about complete bottom of the barrel garbage that won't last a month because it burns itself up. Even the big inefficient AIMS/Sigineers are less than 2%.

IMHO, Phocos is NO different from equivalent MPP solar units except possibly better customer support due to the company name. If you find a MPP solar unit of near identical specifications, I would assume it has the same high consumption.
 
Define cheap.
Victron 5kw have own power consumption of 80-100 watt

Like I wrote the plus that you "always" use extra from the power source.

Low frequency inverters have little higher own consumption then high frequency models, but can withstand higher peaks and longer duration.

30 watt idle is BS. Sales man specs.
No real life.
Not buying unless you show me the real data.

As stated above..
How much on:
500
2500
4500
Drain from battery.

According to their specs 95% efficiency convert DC to AC...

We are not talking about idle here.
Own constant power consumption while working.
Their specs say if you just turn it in with no load at all.. yeah, 30 watt..
Sure.
And as you already stated, that's BS numbers as you are always using the unit.

Guess what..
Own consumption does go up while working, and it ain't part of the 95% efficiency.

So please..
Humor me and provide me the data.

500w + 30w =95% should be 558w drain.
2500. +30=95% 2663
4500 + 30 =95% , 4768 watt.

Betting you 10 bucks you are drawing significant more from your battery.
I assume you have PayPal (I do)
 
Why do I use the number of 85% efficiency as general number for inverters?

Sure I know that there are lab results over 98%.

It's not realistic information.
When you think you have 98% and get 90-92% you are highly disappointed.
Where de 90-92% isn't even a bad percentage looking at the total setup, distance between battery and inverter and used location of the power, and obviously temperature.

When you got your car the brochure told you 18km per liter gasoline.
Yet...
No matter what you do..
You never seem to get that 18km.

Inverters aren't that different.
Specs are nice.

Real life is what matters and that is what you asked.
Not brochure information.

Where 85% might be on the sceptical side...

95% is not something you are able to get.
Some days perhaps close, if the temperature and humidity is right, and distance to battery and power usage are close to the inverter.

Most installations aren't that lucky.
They don't have air controlled environment for their inverter, and their cables aren't as short or thick (or pure) as used for the specifications tests.

Victron. Brand from Holland /Netherlands.

We (Dutch guys) also say "Wij van WC eend adviseren WC eend"
From a Duch commercial..
Roughly translate "we advice our own product"

Dutch humor.

Thrust but verify..
And without verification, the numbers are worth zip.

In USA I believe they say "never thrust a car salesman"
What, with all the "modifications" in the numbers of what a car produce and spits out... Couldn't be more correct.
BMW, VW, Mercedes, Ford, Toyota, Fiat, probably forhot a few companies who bended the numbers in their favour to match the new "targets" :)
Still.... That 18km...
Your not going to get it (on average)
I know of a small VW diesel that actually did do 33km per liter...
No airconditioning or electrical windows...
So sometimes... You might get lucky
 
fhorst, I'd recommend you gather some data and read some reviews first.

I've got three top quality inverters and I've measured the idle loss on all:

A 11 year old 24v Victron Phoenix Multiplus 3000 that just won't die no matter what I've done to it: 32w idle loss
2 year old 24v Samlex EVO 2200w: 23w
Nearly new 48v Outback Radian 8000w: 35w

And then one semi-crappy one:

And then I've got a AIMS 12v 2500W thats doing UPS duty: 56w

And I'm probably not going to bother with the Phocos if its got anything to do with those awful MPP inverters, those thing have a idle loss of 74w as measured by David Poz.
 
Define cheap.
Victron 5kw have own power consumption of 80-100 watt

Nope.

Like I wrote the plus that you "always" use extra from the power source.

Low frequency inverters have little higher own consumption then high frequency models, but can withstand higher peaks and longer duration.

30 watt idle is BS. Sales man specs.

Nope. Legit.

No real life.

Yep. It is.

Not buying unless you show me the real data.

Knock yourself out.



As stated above..
How much on:
500
2500
4500
Drain from battery.

According to their specs 95% efficiency convert DC to AC...

We are not talking about idle here.

Yes we are. This entire thread is about the idle power consumption - The amount of power the inverter consumes when on and actively providing AC power for use when AC power is not in use.

We're not talking about efficiency as you've seemed to extrapolate to.

Efficiency is pretty crappy at low power. 99% of the time when I'm just pulling 50-60W, I'm at a net efficiency of around 65%.
 
SMA Sunny Island SI6048


5750W continuous at 25 degrees C

25W self consumption with no AC load
4W standby consumption (wake periodically to check for AC loads)

As AC load rises from zero W (0W output / 25W consumption = 0% efficient),
efficiency peaks at 1500W load, 94% to 95% efficient (5% loss, 75W self-consumption)
Full load 91% to 92% efficient (9% loss, 720W self-consumption).

We do pay a price for this, $5000 msrp.
Due to distress sales, I got four new-in-the-box SI6048 for $5000 plus shipping.
So my no-load consumption is 100W, have 23kW continuous, 28 kW for 30 minutes, 44 kW for 3 seconds to start motors.

That's usage from battery.
My PV are AC coupled with Sunny Boy. Most of the time battery is full, being floated in the daytime with 0.1kW shown going to them (100W but not enough decimal places to be sure.)
PV through inverter to my loads like A/C uses 95% to 98% efficiency.
But because I have excess PV, much of the production is curtailed when off-grid (on-grid it becomes credits on my bill.)

Battery efficiency is also worth considering.
Lead-acid is something like 70% +/-20%
Lithium is much higher.
 
Standby, own power consumption when using no electricity of 25-40 watts, sure I thrust those measurements.

Efficiency is given as a fixed number in all speciation.
Let's say it's 95%

Yes, you wrote how this "fluctuate" depending on load.

Or, own (idle) consumption is higher at lower power usage.

It's fine by me what you guys like to call it.

On "average" people use about 25% of their rated capacity.
Information from 9 installations, myself included.

At night it's even lower, airconditioning doesn't need to work hard (or cool at all during cool season), same for refrigerator.
When people sleep they tend to use less energy when awake.

Either the self consumption rises at lower power draw, or efficiëncy reduced, end result is the same.

The amount of energy drawn from storage.
That is the same for lead acid and LiFePO4.
What is totally different from efficiency is the amount of energy you put in, and can take back out.

Where I like to say "use 85%" for lead acid and 95% for LiFePO4.
Again, sceptical numbers, both can probably get a few more %.
But great indication on what you really can use.
Many people new to this world think an 12v 200Ah lead acid can give over 2kwh ...day after day after day for 5 years or more..
They don't last 5 years with usage like that.
Edison's will, even 50 years, but they are massive :) really huge.


Real life is what you get when you use it.

Using 600 watt how much is drained from the storage?

At night, for us, cool season even as low as 150 watts..

I have 3* cheaper 3200w China inverters that work perfectly, (and parallel) but do have higher own consumption.
75 watt at 150 watt usage.
35w when I don't use power at all.
That 75w stays the same at 250, 1000 1500 and 2000 watt.*
* Power usage for 1 unit.
Indeed, for my almost 10kw I can have 225w "idle" loss when using all 3 @ lower or higher capacity.
It's stays relative stable, for 500,1000 or 5000 watt.
2 are in use the third is spare or "ready to switch on" if power above 6400 watt is needed.

Perhaps I'm just lucky to have more stable efficiency that doesn't fluctuate.

End of the day, at the end of all the calculations, it matters how much energy is drawn from its storage.
That is the combined number of known power consumption
(water boiler of 600 watt?)
And the combination of self consumption and efficiently where both fluctuate.
What is what is for me not so important.
What is important is that the water boiler (600 watt) really does use 700 watts* stored energy at my house.
* On 1 inverter.

Cool season with 150 own power, I drain 300w.
That's fine.

I didn't want to spend $5000,-
But bought "a few" more panels and 15kwh battery extra..
Now my mining rig that uses 750w 24/7 have enough juice :)
It makes just 5 to 6 dollars a day.
But "earns" a new Victron in 3 years..

Low frequency inverters usually use more idle, it's the massive heavy coil...
With the famous slight humming sound.
But.... They "don't die"..
Controlling PCB might need replacement after 10 or 15 years, the coil will be working fine after 30. With the efficiency of 30 years ago... Probably newest controllers can boost a few%. You never need to buy new.
Depending on your wishes... It can be the best solution

High frequency Inverter...
Indeed, all about the quality of the components.
They won't last 30 years.
I expect my cheaper China models to last 5 to 7 years.
Victron 10-15 years.

At 10% of the price...not a bad tradeoff.

Sure. Rolls Royce, Bentley, Maserati, Mercedes...
Or Outback, Victron...
You pay top dollar and get quality (most of the time)

That's no reason to talk negative about MPP Solar, Growatt, Sorotec or EPEver.

We don't all drive a Rolls...
Have Rolex and talk about the low quality of Adidas compared to Balenciaga pool side sandals....

Just don't try to compare them.

I can't afford Balenciaga pool side sandals for $295,-
Nor a Victron or outback for $5000,-
We aren't all American.

Indeed, great "great first-pass indicator of the quality of the unit"
Probably the purchase price, 20% of Victron, should already tell you enough.....

Still a great unit with amazing capabilities for its price.
And the $4000 that you save now is enough to buy one spare, 15kwh extra battery (LiFePO4 ) and 15kw solar ( 35* solar 435w)

It's not a show off to the club.
But beats the -peep- out of the Victron at the end result.
Solar power production, total storage capacity and consumption availability.

I did read about micro inverters.
Enphase IQ 7 97% efficient and 25 years of warranty.
For about $125 per 440 watt..
You get an 17kwh inverter :)
Sadly.. only when the sun is shining.

If I would be grid tied, those are my first choice for efficiëncy and quality.

And small (10-15kwh) backup system for the night if there is power failure @the grid.

Grid tied, with $5000,- budget, and probably already more then 35* 450w pannels, aiming to last with minimal maintenance or supervision... It's a tough one to beat that IQ7
 
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Here's the efficiency data for Sunny Island.
As you said, what matters is how many Wh are consumed.
This one will use 600 Wh/day plus a portion of AC load supplied. That isn't a fixed percentage - it is I^2R losses, so goes up as square of current or power delivered.

SMA's transformerless high voltage battery product data sheet quotes 96.5% to 97.5% (CEC and Max) efficiency, but doesn't show the curve.
At least for the U.S. 120/240V split-phase market, a low frequency transformer is also used. Efficiency not quoted.

I would say SMA offers particularly high efficiency for grid-tie systems, a bit lower for battery backup.

SI 6048 efficiency.jpg
 
IMO the best value for the 'quality' inverters are the Samlex EVO line. Yeah they cost a bit more than the Aims/MPP/etc but nothing like the ape-raping I got when I bought the Radian. The downside is they only come in 24V or I would have gone with them. A 4000W inverter with a good surge capacity for $1350 isnt too shabby. And you can stack them.

@Hedges thas a nice curve. $5k for a inverter is more than I'm willing to spend tho - I thought $3800 was way too much.

radian_efficiency.JPG
 
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Just for comparison if you find someone who has actually measured a Phocos idle draw, my old Outback VFX3648 (discontinued) specs at ~23 watts idle and my shunt indicates about half that usually. Rated at 30A AC continuous output with 100ms surge of 50A.
 
i think it is a Axpert vmii clone be warned of the float bug
Don't think its a Voltronic Axpert, or any of the Voltronic inverters, the specs are completely different - especially in the MPPT voltages.

After a lot more digging I've found out Phocos is its own company, headquartered in Germany and manufactured in China. They appear to be a near-'tier 1' inverter.
 
Don't think its a Voltronic Axpert, or any of the Voltronic inverters, the specs are completely different - especially in the MPPT voltages.

After a lot more digging I've found out Phocos is its own company, headquartered in Germany and manufactured in China. They appear to be a near-'tier 1' inverter.
have you ever tried to run watch power ( voltronic software ) on it. it will work, manual has the same error codes. but still Phocos can use different parts and better parts. hopefully they have solved the problem. MPPT voltage is more or less the same 450v vs axpert 500 v max recommend 450v
 
have you ever tried to run watch power ( voltronic software ) on it. it will work, manual has the same error codes. but still Phocos can use different parts and better parts. hopefully they have solved the problem. MPPT voltage is more or less the same 450v vs axpert 500 v max recommend 450v
Phocos is 250V which is exactly the voltage I'd need.

Voltronics appears to be behind all the (IMO) awful MPP & MPPish inverters on the market.
 
Ive finally successfully installed my Phocos all grid 5Kw inverter. Works well. It's been running for 2months now. (Rather Well). ive included the 40kwh (48 x 100AH x 8), lifepo4 battery bank. all seems to be ok. have been monitoring the bank and it hasn't been above 53.7v (charging at night, off the mains and day with solar). Solar is running well.
 
Ive finally successfully installed my Phocos all grid 5Kw inverter. Works well. It's been running for 2months now. (Rather Well). ive included the 40kwh (48 x 100AH x 8), lifepo4 battery bank. all seems to be ok. have been monitoring the bank and it hasn't been above 53.7v (charging at night, off the mains and day with solar). Solar is running well.
53.7v isn't so high. 3.356v
If I would call a SOC based in the voltage, it would be about 70%.

Charging at night of the the grid??
I don't quite understand.

You meen discharge to the mains of your house?
And charging during daytime on solar??

Anyways, if you have enough energy, it's OK. You probably don't use full capacity, but it does extend the lifecycle.

If you don't have enough energy with the 53.7, I would adjust the profile settings.

Please do use BMS, especially when you care charging above 3.4v
I suppose you have, just in case...
Better to be warned then bloated :)

What is the current profile setting?
 
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