Starter battery still charging after 14 hours whilst static

I fitted one of these (used to be in our old motorhome) and have to date never had a problem with vehicle battery no matter how long we are off grid.
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Why use this product instead of a voltage sensitive relay?
A voltage sensitive relay takes a relatively large amount of charge to hold in a relay. This is power you cannot afford if you are only producing low current (e.g. from solar / wind input). The Battery Maintainer uses FETs instead of relays and as such uses very little power itself (less than 1 mA) thus solar input can be more efficiently used. The Maintainer is also current limiting so the high load on starting would not affect it. Relays also have a limited life cycle and on low power generation a relay could be clicking ‘on’ and ‘off’ all day. However, with a FET control system there is no physical contacts to wear out and no noise produced. This Maintainer should not be used on a battery with a sustained heavy discharge/drain as it can’t pass high currents. See Voltage Sensitive Relays or the Battery to Battery Chargers section.
A 100Ah battery at 50% discharge would take about 24-36 hours.

How does it work?
This unit is activated when the main battery has reached about 13.3V and allows excess power to be transferred from the primary charging system to charge / maintain an auxiliary battery bank.
Please note that this product has no fast charge / boost ability but simply mirrors the input voltage with a small voltage drop (depending on the current flow), the final charge voltage would be around 0.2V lower than the primary charge voltage. This is more than enough to keep a battery topped up and supply any small loads, such as: the battery internal discharge and the engine management system discharge (up to about 1A continuous). This product should not be used on a battery with a sustained heavy discharge or drain as it does not have the ability to pass high currents, for higher currents see the Voltage Sensitive Relays or the Battery to Battery Chargers sections of the catalogue.
This maintainer has the ability to charge and maintain the charge, even if the battery is low (in a long time frame for example a 100A battery at 50% discharge could take about 1-2 days) it would never do this if the current discharge from that battery is in excess of 2A.

I have it connect to my 180amp battery and feeding vehicle battery, so keeps it charged up. Not cheap, but better than replacing battery if setup not right.

Look here: Link
 
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Hi Dell

I’ve ordered the AM12-2 and have the van booked in for a week when I go away.

The powering up or humming does draw quite a lot as the pics show but more concerning is the 7% drop in SOC overnight, in fact at around 4 this morning I was just sat in the van with nothing on with the side door open and it powered up on its own and then later the wipers didn’t work, changed the fuse and still didn’t work but now they’re fine again, might be totally unrelated.

When I said previously that when turned off the LB was still being charged and I assumed from the SB I made a mistake, I had forgotten the solar panels, my bad.

I think primarily I need to find out
1 What is drawing from the SB
2 Tweak Orion settings
3 Fit AM12-2

As a side note, when I was working in Port Talbot for the month I never had a single issue with the LB’s and I think that is because I’d be doing some driving daily anyway.

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Got all three batteries, starter plus 2 x LB to 100% yesterday with Charger, Sun and EHU.

Overnight the SB dropped 5% and the LB 8% with nothing on at all.

Turned the charger back on to see the charger was charging both the starter and both LB’s, is that normal?

I hope it’s not because then that might mean my SB is discharging into LB.
 
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Got all three batteries, starter plus 2 x LB to 100% yesterday with Charger, Sun and EHU.

Overnight the SB dropped 5% and the LB 8% with nothing on at all.

Turned the charger back on to see the charger was charging both the starter and both LB’s, is that normal?

I hope it’s not because then that might mean my SB is discharging into LB.
The overnight drop will be the surface charge dissipating from the batteries. Leave them alone for a couple of days & then see what they’re reading.
 
If you are monitoring SOC by measuring voltage, then you need to realise it refers to an unloaded battery. If you draw current, then the battery voltage drops - if you draw lots of current, it drops a lot.
Looks like at 3:48 the Orion stars charging the leisure battery and the SB voltage drops - if you unload it, the voltage will rise again. -you just need to tweak the Orion settings as Dellmassive suggested - it shouldn’t be turning on overnight.

Nothing else sticks out to me from the readings you’ve shown

Simon
 
Thanks Salty / Simon

I’ll leave for a couple of days now and continue to monitor.

So can the Orion physically charge the LB from SB without ignition on and yes, will tweak the settings, the vans going in for a week on Monday.
 
Thanks Salty / Simon

I’ll leave for a couple of days now and continue to monitor.

So can the Orion physically charge the LB from SB without ignition on and yes, will tweak the settings, the vans going in for a week on Monday.
Yes - this is exactly what’s happening - you need to tweak the settings so it doesn’t
 
Thanks Salty / Simon

I’ll leave for a couple of days now and continue to monitor.

So can the Orion physically charge the LB from SB without ignition on and yes, will tweak the settings, the vans going in for a week on Monday.
Yes if it isn’t setup correctly. By far the best way of controlling the Orion (IMVHO) is by an ignition live. I’m not convinced with the engine detection.
 
Just a quick observation, unrelated to the problem, but aren’t those two Hankook batteries ‘starter’ batteries of 80 ah each?
That’s about 60kg of batteries giving a useable 80ah. You could have one 11kg 100ah LiFePo giving you the same useable power plus an extra 20 ah on the odd occasion.
Or two LiFePo giving you 160 useable ah.
 
Thanks for the advice, I’ll be upgrading to LiFePO4 after they find out where the drain from the SB is going and tweaked the Orion.

I’ve got them all on charge again, solar, EHU and charger for SB but the battery monitors show the charge passing through the SB to the LB without charging the SB.
 
Thanks for the advice, I’ll be upgrading to LiFePO4 after they find out where the drain from the SB is going and tweaked the Orion.

I’ve got them all on charge again, solar, EHU and charger for SB but the battery monitors show the charge passing through the SB to the LB without charging the SB.
Do you have any USB sockets on your LB side?
Do you have access to VCDS or any other diagnostics? You will be able to see the parasitic drain on the SB.
 
I only have USB through a 12v adapter and have no idea what a VCDS is, sorry.

I have had a conductive clamp on a cable coming from the battery which spikes around 5A when you open doors with the humming sound for about a minute and settles at 0.05A after.

It looks like the SB is either draining into LB or forced to by the incorrect Orion settings.

It’s a tad annoying the SB is only charged on overrun or braking despite how charged it might be.
 
Can you disconnect the SB from the Orion and see if it still has a drain? That would surely confirm whether or not the SB is draining into the LB.
 
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