Victron 12/40 shore charger

Ok so now I know charger big enough and cables ok , batteries I sure are fine as there are all new .
So why after I managed to get the Amps to drop so it's only charging at 2A , turning every thing off ( charger and engine and leaving to the solar panels 320w panels in all I don't see and change in voltages over the day .
Load 3A ?
 
Amps dropping from 20 to 2.2 in 20 minutes, with a 450ah battery bank isn't right.

Just because the batteries are new, doesn't mean they are all good. Should be, but check anyway.

The charging cables do want changing, they are under spec. Won't make a massive difference, so don't panic, get a set of 16mm cables when convenient.
 
Amps dropping from 20 to 2.2 in 20 minutes, with a 450ah battery bank isn't right.

Just because the batteries are new, doesn't mean they are all good. Should be, but check anyway.

The charging cables do want changing, they are under spec. Won't make a massive difference, so don't panic, get a set of 16mm cables when convenient.

Plainning to do the same test to morrow just in case I got or wrote some thing down right . .
 
Plainning to do the same test to morrow just in case I got or wrote some thing down right . .


:encouragement:

Try with just the mains charger Vic. Too many charging sources can cause confusion.

Also worth noting, running the mains charger early in the morning, before the solar controllers have started will cause you some issues, particularly with the Victron controller. It will see the mains charger voltage, assume the batteries are more charged than they are, and go into float early. I know that's not happening now, as you probably aren't turning the mains charger on before they start, but worth knowing nonetheless.
 
:encouragement:

Try with just the mains charger Vic. Too many charging sources can cause confusion.

Also worth noting, running the mains charger early in the morning, before the solar controllers have started will cause you some issues, particularly with the Victron controller. It will see the mains charger voltage, assume the batteries are more charged than they are, and go into float early. I know that's not happening now, as you probably aren't turning the mains charger on before they start, but worth knowing nonetheless.
Yes I Knew that , so I didn't start the test untill the Victron started working .
Out of interest Paul , I know it's only wild guess work on your part , but say as I this morning the SOC is 70% .
How long would I need to run the charger , before there a good chance the Victron mppt with the help of the charger would be able to reach Absorption?
Using 320w panels in all and it should be a sunny day to morrow ? Or is it not possible to guess .
 
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Yes I Knew that , so I didn't start the test untill the Victron started working .
Out of interest Paul , I know it's only wild guess work on your part , but say as I this morning the SOC is 70% .
How long would I need to run the charger , before there a good chance the Victron mppt with the help of the charger would be able to reach Absorption?
Using 320w panels in all and it should be a sunny day to morrow ? Or is it not possible to guess .

A lot of variables to factor in Vic. At 70% you need to put about 135ah back into the batteries, add a bit for inefficiencies, then add whatever you'll be using. Could easily be looking at 200ah, that's 20a for 10 hours, on paper, but the last few % take even longer to squeeze in, so you've got your work cut out to get them fully charged. You'll need to make sure those two solar controllers are both putting out as much as they can and not interfering with each other. Try monitoring them separately to see how they do.
 
Just a thought. Given that the batteries have recently been changed I wonder whether the connections from charger to battery are overheating due to poor contact and hence leading to increased resistance once hot.


If you have a pair of victrom MPPTs have you considering interfacing them with a Raspbery Pi.

see

https://www.victronenergy.com/blog/2017/09/06/raspberry-pi-running-victrons-venus-firmware/

I have done so and its a relatively inexpensive way to monitor whats going on.
 
Another question the analog gauge on the Victron shore charger , what is that showing .
Current going into the batteries from the charger .
Urgent being accepted by the batteries ?
All current the batteries are accepting from everywhere ( other charging sources)
Or just the current that being split between the two batteries banks ?
 
Just a thought. Given that the batteries have recently been changed I wonder whether the connections from charger to battery are overheating due to poor contact and hence leading to increased resistance once hot.


If you have a pair of victrom MPPTs have you considering interfacing them with a Raspbery Pi.

see

https://www.victronenergy.com/blog/2017/09/06/raspberry-pi-running-victrons-venus-firmware/

I have done so and its a relatively inexpensive way to monitor whats going on.
Connection are ok but thanks for the input .
My second MPPT is a solar and not a Victron , shame really , but it seen to work very well if you can believe the reading .
 
Another question the analog gauge on the Victron shore charger , what is that showing .
Current going into the batteries from the charger .
Urgent being accepted by the batteries ?
All current the batteries are accepting from everywhere ( other charging sources)
Or just the current that being split between the two batteries banks ?

It is showing output current from the charger. It will be split between the two banks, to what degree obviously depends on SOC of the engine battery. The amount of charge reaching the batteries will also be dependent on load. If the charger is outputting 30a but you have total loads of 10a, only 20a will be devoted to charging the batteries.
 
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