Quattro 48/10000 Temp Compensation Charging

Question

question

justin-k asked Apr 8, '19

Quattro 48/10000 Temp Compensation Charging

Hi All,

Looking in the documentation and on the forums I have found a theme but no relevant detail regarding Temp compensation.

I have ,a few times, come across -16mV/12V block. (equates to 2.67mVpc/C). Multi etc.

I am using Enersys batteries which require -4mVpc/C.

This also appears to be the value for Victron's own VRLA batteries.

There appears to be no way to change the Quattro settings for this (VE config) and its not a setting on the CCGX (wouldn't expect it here) or BMV.

In my case compensated Voltages (using -2.67mVpc/C) from 10C to 25C are below manufacturer recommended but above their minimum requirement, sleight concern. Above 25C the Compensated Voltages are above the recommended, there lies a greater concern.

Its impossible to get get an accurate picture from Appendix F of the manual, the recent multi discussion showed a new diagram which was much clearer.

Am I missing something or is this an upcoming revision as indicated in the recent Multi discussion.

Could anyone offer any guidance?

Best Regards

Justin K

temperature compensation

1

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

justin-k commented · Apr 09, 2019 at 10:12 AM

For clarity: i am using the temp senor connected to the Quattro.

0 ·

Modifications Space

Node Red Space

Answer 1 · 2019-05-01T12:42:54Z

Mark answered · May 01, 2019 at 12:42 PM

Hi Justin,

I have the same issue/concern - I asked the same question a month or so ago & did get the correct answer in the end - see link;

https://community.victronenergy.com/questions/10993/multiplus-charge-voltage-temperature-correction.html

Basically the temperature compensation graph in the back of the MultiPlus manual is incorrect (I expect the Quattro to be identical). The default coefficient changed (reduced) as of a few firmware revisions ago, but the manual was not updated.

Currently there is no way to change the default coefficient, but @mvader has confirmed that Victron will make this user configurable in a future firmware / VE Configure update.

Until then I just need to be careful if temperatures are significantly different to the default 25°C nominal & manually adjust the charge voltage using VE Configure if & as required.

This is far from ideal but I don't want to kill or degrade my new batteries prematurely & hopefully it's only short term.

I don't know why this issue isn't getting more attention / urgency placed upon it - as correct / accurate charge voltage (including voltage compensation due to temperature) is really a fundamental requirement to get right.

Hopefully the update / fix comes soon...

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Answer 2 · 2019-05-03T13:40:15Z

justin-k answered · May 03, 2019 at 01:40 PM

Hi Mark

I did some quick excel work ( I think my numbers are correct) and for me things aren't working out too bad (still far from ideal. I have a containerised solution with a 48V 1360Ah battery.

At the lower temperatures with temp compensation I'm still above the minimum recommended temp compensation value Vpc. Grey Manufacturer Min, Blue Victron with temp comp, Orange Manufacturer recommended.

Above 25C I will be overvolting but my hopes are that with the British climate and the units being located in exposed areas that these high temps wont be reached at all (or hopefully for any length of time).

Although with the cost of this particular battery block it doesn't bear thinking about. Hopefully this will be resolved soon.

BR

Justin

temp-comp-graph.jpg (28.1 KiB)

2 |3000

Attachments: Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

question