Victron Ess Charge Settings

[PaulF007]

I will post some picks later but I made the brave dive into Victron with all of it various settings. I am running ESS but there is a setting that I am missing on the charge controller.

The MPPT does not go to bulk charge. Keep in mind that I draw my batteries down to a max of 85%. I am quite new to this part so what info should I pass along?

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47 minutes ago, PaulF007 said:

The MPPT does not go to bulk charge

What do you mean by this, and based on what did you conclude this?

Bulk charge just means the solar charger is throwing all the current it can into the battery because it hasn't reached the absorption voltage yet. When running ESS the charging state is synced between the Multi and the charge controllers, so the entire system has one state, with the Multi being the boss of them. On the CCGX it displays the general "system state", and I've had more than one person report to me that the "Discharge" state is confusing because they think it ought to display the charging state. Similarly, when it used to display the charge state... people complained that it was confusing because it shows Bulk while the battery is actually discharging :-)

[PaulF007]

Hi @plonkster

The settings (on the charge controller) I have is bulk  57.2 v and Absorb/Flout is 54 v 

The last two days the charge volts did not go above 54 v. So that is why I believe it has not gone into bulk.

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5 hours ago, PaulF007 said:

The settings (on the charge controller) I have is bulk  57.2 v and Absorb/Flout is 54 v 

There is no such thing as a bulk voltage (not in Victron land :-) ). There is absorption voltage and float voltage.

In an ESS system the solar chargers are controlled by the Multi, the configuration of the MPPT itself is only as a backup (should it lose communications with the CCGX).  It should follow the voltages configured with veconfigure. 57.2V seems like it was done on purpose, that's 14.3V per 12V battery.

(Seeing as I was there when this thing was configured the first time... you'd think I can remember what we set it to :-) ).

If you have a temperature sensor attached the Multi also derates charging voltage and might go for something lower. Another thing to take into account.

Something else to look at: From your CCGX's device list, navigate to a solar charger, and then to Networked Operation. There it shows the Charge Voltage that the MPPT is set to (will be set higher than configured on the multi while in bulk, to compensate for losses).

Also, I showed you how to root it. There is an application on it that you can use to inspect the various services, called dbus-spy. If you run that, and go to the vebus service, and look at /Hub/ChargeVoltage: That is the value the Multi sets the MPPTs to.

If those values are nice and high, yet you don't reach more than 54V... well then you're probably using more of the power directly and less of it ends up charging the batteries :-)

[PaulF007]

@plonkster thanks for the response!

23 minutes ago, plonkster said:

Also, I showed you how to root it. There is an application on it that you can use to inspect the various services, called dbus-spy. If you run that, and go to the vebus service, and look at /Hub/ChargeVoltage: That is the value the Multi sets the MPPTs to.

 The value there is now 54.38 so I should set it to 57 again? The only other thing that changed was that I added the temp sensor to the Multi but will disconnect that in the morning. 

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1 minute ago, PaulF007 said:

54.38

Such an odd voltage almost certainly indicates that it is doing something with temperature. IIRC it derates by -16mV for each °C above 25, and similarly below it (but it caps the temperature at -30°C). So one way to test it is to remove the temperature sensor and see what happens then. @9xsolar had a similar issue with his  temperature sensor. Still not quire sure what happened in his case, whether it was a faulty temperature sensor or whether his batteries really were above 40°C :-)

[PaulF007]

24 minutes ago, plonkster said:

So one way to test it is to remove the temperature sensor

Ok thats first place to start , today has been a cold day here so the sensor was'nt close to 40. Will have a look tomorrow and report back !

[PaulF007]

@plonkster it seems like the temp sensor was to blame. I disconnected it and the controller went to bulk charge again.

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4 hours ago, PaulF007 said:

temp sensor was to blame

It would be great if you could give this a test to see if it behaves correctly, maybe dipping it in luke warm water (cover in a plastic bag perhaps) of a known temperature. Not that there is any reason to suspect that it doesn't, but this is the second time I heard of what seems like it overreacting. As all our test rigs seems to gravitate towards LFP now, I don't often get a chance to test this. Sadly the Multi doesn't publish its internal temperature anywhere, but the previous time I saw this I worked backwards from the temperature and the customer assured me his batteries are not above 40°C.