Powerassist on Victron Quattro 48V 5KVA inverter

[Darkstar]

Is it possible to have Victron powerassist kick in below 13 amps load? I have an AC line in source that can only supply a maximum of about 4 amps. I want the quattro to use the AC input line up to about 4 amps and then anything above that should be supplemented from the attached LiFePo4 Battery. When I set the input current limit to anything less than 13 amps from my Venus GX device (Attached to the inverter by a MK3-USB cable) the Venus GX display automatically reverts the entry to 13 amps. When I try to set the input current limit directly on the inverter via Remote VE Configure, it does not seem to actually change anything in the inverter. In other words powerassist never kicks in when a large load is applied to the inverter. The inverter just switches from bypass mode directly to battery supply only mode because the inverter load overloads the external AC source input.

Latest Quattro firmware has been installed.

I have tried with "Overruled by remote" checked and unchecked.

I have tried with "Dynamic Current Limiter" checked and unchecked.


The whole point of spending this much money on this inverter was so that I could take advantage of a small AC input source from a separate
hydro-electrically charged system here on the property to supplement the solar charged system that the Quattro is attached to..

 

[snoobler]

How clean is the AC input power? The Quattro has to sync with it to piggyback, and it can reject it.

Do you have the transfer switch configured as follows:



I can reconfigure mine via VRM config file download, edit on PC w/VE Config 3 and then upload via VRM. For the life of me, I can't find that setting on the remote console of my CCGX.

What about PA boost factor? You need a higher number?

Assist current boost factor​

This setting is a special setting for PowerAssist. When the Multi is charging and, due to a sudden load, the mains current exceeds the AC input current limit the Multi will switch to assist mode (when enabled, see PowerAssist).


At that moment the current needed is unknown. The Multi makes an assumption of the magnitude of this current. This assumption is equal to the AC input current limit multiplied by this "Assist current boost factor" setting. The default factor is two. This will prevent the circuit breaker from tripping because current provided by the inverter minus the current drawn by the load is always lower than the rating of the circuit breaker. This, of course, when the AC input current limit is correctly adjusted to the circuit breaker.


If, for instance in a generator application, the circuit breaker has a higher value than the AC input current limit. (Nominal capacity of the generator is lower than the maximum peak load) and one knows that the load which is switched on always draws a certain current one can consider to increase this factor to achieve better results with sudden load changes.

 

[WilliamC]

If only Victron made an inverter with 120/240 vac split phase output.

 

[snoobler]

They kinda do. You order the 230/50 unit as a 240/60 and pair it with an autotransformer.

 

[Darkstar]

How clean is the AC input power? The Quattro has to sync with it to piggyback, and it can reject it.

Do you have the transfer switch configured as follows:

View attachment 31369

I can reconfigure mine via VRM config file download, edit on PC w/VE Config 3 and then upload via VRM. For the life of me, I can't find that setting on the remote console of my CCGX.

What about PA boost factor? You need a higher number?

View attachment 31370

Assist current boost factor​

This setting is a special setting for PowerAssist. When the Multi is charging and, due to a sudden load, the mains current exceeds the AC input current limit the Multi will switch to assist mode (when enabled, see PowerAssist).


At that moment the current needed is unknown. The Multi makes an assumption of the magnitude of this current. This assumption is equal to the AC input current limit multiplied by this "Assist current boost factor" setting. The default factor is two. This will prevent the circuit breaker from tripping because current provided by the inverter minus the current drawn by the load is always lower than the rating of the circuit breaker. This, of course, when the AC input current limit is correctly adjusted to the circuit breaker.


If, for instance in a generator application, the circuit breaker has a higher value than the AC input current limit. (Nominal capacity of the generator is lower than the maximum peak load) and one knows that the load which is switched on always draws a certain current one can consider to increase this factor to achieve better results with sudden load changes.

Not sure how clean the power is. It is from a pure sine wave Xantrex inverter which is 300' away via 10/2 uf

My transfer switch settings match those above.

Screenshot from my VRM remote console showing "Input current limit": (Which I can't set any lower than 13)



I have not tried changing the boost factor. Guess it's worth a shot.

 

[snoobler]

I wouldn't expect that to be dirty. Put your tester on it. Volts? Hz?

DOH! mine was opening that menu at the "AC-in L1" screen, and I thought that was the top. Scrolled up and found it. Thanks.

Mine won't let me adjust below 13.5A via the remote console. I normally keep it at 14.5A because I'm limited to a 15A 120VAC plug on my generator. No idea why this is happening, but since I'm already trained to use VE Config via a downloaded config file via VRM, I don't care to do it via remote console anyway.

Given the stated example and the typical 15A limit on an input circuit breaker, if 2X is intended to permit up to 30A, a 4A input limit would need a 7.5X factor to produce the same. I'm just guessing here. Of course, it might need to go the other way.

When programmed to 4A directly, it may be that the inverter is functioning as desired, but there's a delay before it starts pulling from the AC-in when PA is triggered, and it may depend on battery voltage. It may be deciding that since the load is too much for the AC-in, it's going to take it over completely and then allow AC-in to contribute once the situation is less dynamic. At a minimum, I have to believe that the battery voltage dropping to float will force it to use AC-in to charge. While you may miss out on the short term contribution, 4A of AC-in keeping the battery in float is essentially still harvesting the AC-in power.

Have you left the unit running for 5+ minutes and checked back to see if you're getting your 4A AC-in?

 

[Darkstar]

I wouldn't expect that to be dirty. Put your tester on it. Volts? Hz?

DOH! mine was opening that menu at the "AC-in L1" screen, and I thought that was the top. Scrolled up and found it. Thanks.

Mine won't let me adjust below 13.5A via the remote console. I normally keep it at 14.5A because I'm limited to a 15A 120VAC plug on my generator. No idea why this is happening, but since I'm already trained to use VE Config via a downloaded config file via VRM, I don't care to do it via remote console anyway.

Given the stated example and the typical 15A limit on an input circuit breaker, if 2X is intended to permit up to 30A, a 4A input limit would need a 7.5X factor to produce the same. I'm just guessing here. Of course, it might need to go the other way.

When programmed to 4A directly, it may be that the inverter is functioning as desired, but there's a delay before it starts pulling from the AC-in when PA is triggered, and it may depend on battery voltage. It may be deciding that since the load is too much for the AC-in, it's going to take it over completely and then allow AC-in to contribute once the situation is less dynamic. At a minimum, I have to believe that the battery voltage dropping to float will force it to use AC-in to charge. While you may miss out on the short term contribution, 4A of AC-in keeping the battery in float is essentially still harvesting the AC-in power.

Have you left the unit running for 5+ minutes and checked back to see if you're getting your 4A AC-in?

Good, fresh ideas. Thanks

Max setting on boost is 3.5.

When I set to 3.5 Boost there is no noticeable improvement. The inverter turns off pass through and charger and then tries repeatedly to switch back to pass-through and charger mode without success. Tt then returns to charger/pass through mode once inverter load is removed.

When I set to the minimum boost of .3 the inverter turns off pass through and charger and then once the load on inverter is removed it does not switch back to pass-thru nor does it turn the charger back on.

At boost level 1 it performs similarly to boost level 3.4

Will test 5 min run time later.

 

[cinergi]

You can't go below 13.5A minimum current draw. I asked about this and Victron said that any lower is just not practical for such a large unit. They already lowered the minimum setting once on customer request so that it can fit the use case of connecting to 120v shore power like RVs do.

 

[Darkstar]

You can't go below 13.5A minimum current draw. I asked about this and Victron said that any lower is just not practical for such a large unit. They already lowered the minimum setting once on customer request so that it can fit the use case of connecting to 120v shore power like RVs do.

Dang, that sucks. Wish that was made clear somewhere in the brochures or docs. I specifically went with the Quattro for this feature.
I do have a workaround but I spent too much on that inverter for a feature that does not work for me.

 

[Darkstar]

My workaround is to use a full wave bridge rectifier feeding DC to a Bluesolar MPPT charge controller. Have seen 97% efficiency, not counting the conversion losses on the inverter at the other end of the cable nor the cable loses.

Works pretty well but I wish Victron had made that limitation clear somewhere. That is the one gripe I have about them. Their documentation is far from comprehensive, you have to search far and wide for info on many of the functions/features of their products...

 

[Darkstar]

Does anyone know if there are different powerassist lower amp limits on other Quattro/Mulitplus sizes? Anyone know what those lower limits are?

 

[cinergi]

Does anyone know if there are different powerassist lower amp limits on other Quattro/Mulitplus sizes? Anyone know what those lower limits are?

Create a free Victron Professional account (https://professional.victronenergy.com/) and go to Firmware, VE.Bus (Multis, Inverters and Quattros) and then find the "minimum shore current limits 07-2019.xlsx" document.

Edit: make sure you look at the 120v versions at the bottom

 

[Rocketman]

I think My Multiplus 12/3000 has a lower limit of about 7 or 8 amps of ac input. It would be a while before I could verify that though. (RV is far away) That's what came to my memory from when I was playing with the unit when I set it up. (but its been a while...)

 

[cinergi]

Every model's exact limit is documented in the spreadsheet above.

 

[tricky74]

The power assist seems to work backwards for the application I want it for.
Have not yet purchased but have been looking at a Multiplus.
I have good 240v ac but want to run 100% off battery when possible.
On a sunny day I want the system to run off solar and batteries.
On a cloudy day if the load is greater than x then I want to assist the batteries with ac shore power.

 

[Rocketman]

Look into Victron’s ESS. - I don’t know anything about it - except it’s not what I want to do in my RV. I believe it does what you are looking to do.

 

[tricky74]

Anti islanding looks to be more of an issue. Cost of relay is more expensive than any gains to be had from the system.
Looks like turning the ac power from mains off is the most cost / performance effective solution for me.

 

[JoeHam]

Looks like turning the ac power from mains off is the most cost / performance effective solution for me.

I have the exact same goal and the same work around solution with my Schneider CSW4048.

On occasion I forget to flip the 240v mains breaker back on when the battery gets low and my wife has further proof that I’m an idiot ?. Since the fridge is on my critical loads panel it’s a tattle tale.

It’s only a problem in the winter as the system keeps up in the summer with the 240v grid feed off just about 100% of the time.

Edit: IIRC the CSW4048 always draws just under 2 amps while I have the breaker on to qualify or sync the grid power with the inverter power.

A system like Darkstar’s could use the hydro to cover this but not much advantage to be gained.