Charging options

[Nabsim]

Was going to post this in one of my other threads but think it its own thread. Winter is getting closer so time to sort what I am going to do with mains charging. My generator is a Hyundai 1Kw rated at 900W continuous. While a bigger genny would give me more options I can handle this one and would struggle with a 2 or 2.2kw unit so I need to get the best I can to suit this. My battery bank is 2x100ah Lifepo4 battery’s plus I want to trickle charge to my starter battery

Charlie has a Ring 50a smart charger and that doesn’t run on the 1Kw genny, it needs more power. So far the best I can see in a single unit is the Votronic Pb 1250 Smt automatic charger at 840W.

The biggest single unit Victron is 30a, I would either need to get two smaller chargers or go to a MultiPlus I ‘think’ to use Victron.

I liked the second hand Votronic VAC 1230 30 Duo chargers but seller is still away and they are a little over my 900W limit. Not sure if I can adjust these to deliver 25a per outlet, does anyone know, that would bring it in on the 900W limit?

if I am only going to accept 30a then I will probably go with the Victron 30a 3 output charger but it isn’t really what I want.

Links to all three chargers below this, anyone got any other possible contenders or recommendations bearing in mind limitations in first paragraph?

VOTRONIC - Pb 1250 SMT 3B

Innovative Elektronik für den mobilen Einsatz

www.votronic.de

VOTRONIC - VAC 1230/30 Duo

Innovative Elektronik für den mobilen Einsatz

www.votronic.de

Victron Blue Smart IP22 Bluetooth Battery Charger - 12V 30A, 3 outputs

Victron Blue Smart IP22 6-stage battery charger 12V 30A (3 output). Multi-stage, Bluetooth-enabled charger for boats, caravans, motorhomes, campervans.

www.12voltplanet.co.uk

 

[wildebus]

What is your Solar Controller? (this could be an option)

For bigger Victrons, it seems that the Multipluses are only a little bit more expensive than the high-power chargers, which is daft, and does push you towards the Combo units - but to properly control the Multiplus you would need to add in an external unit, so add in another £60 or so.

for some bulk charging, you could run the existing charger unit you have in parallel with an additional one such as the Victron 30A unit - rolling them all together will put some nice charge in the batteries

The VAC1230/30 Duo does not state it is compatible with Lithium. Given they DO say the Pb 1250 SMT 3B DOES have a Lithium Profile (funny for a charger with "Pb" in it ), then I would be inclined to not want to use the Duo on my expensive Lithiums as there maybe something about it that stops them adding Lithium support in the features?

That Pb 1250 SMT does sound quite good (but I do have a few doubts on Votronic stuff right now after looking into their 'Battery Master' device in the last few days (https://www.votronic.de/index.php/en/products/peripheral-units/cut-off-relays) - Around £28, which is around £27 too much)

I am guessing you are looking at the Victron 3-output charger so you can connect one output to the starter? That may not be a good idea as the voltage the Starter Battery wants is quite likely a fair bit lower than the optimum charge voltage the Lithiums want, and with that charger, the current varies between outputs but the voltage doesn't.
Either a 12V-12V trickle charger or a dedicated charger for the starter would be better - if just a trickle and you don't want a modern programmable 12-12 Battery Maintainer (such as the AMT-12) , then just get the cheapest little charger around for that battery?

 

[Nabsim]

The Duo would have to run on Gel settings Dave. I motitor my batteries and don’t mind disconnecting the rare times I get hookup, with genny I wouldn’t run long enough to float (30 amp to each battery 60 amp total). No dedicated setting isn’t ideal though.

I have used Votronic solar and B2B chargers for a while now and very happy with the brand. I am looking at maybe changing my solar controller as it’s always been too small (250 Dou and 300W panels) but I only lose in summer when I have excess anyway. If I change I will probably go Votronic again (350 Duo) as if I am reading right I need to jump up a fair bit of cash to get one that takes all 300w.

I currently run the schaudt 18amp charger in my ELB supplemented by a second schaudt 18amp charger. You would thin (or I did) that would mean max of 36 amps but most I ever see is 24 amps and not for long. Existing chargers use Gel settings which do suit Bolts wise with me managing how long they run just not enough amps.
I hadn’t thought of running the Victron 30amp in parallel with the EBL, that may well be worth a go,

 

[Nabsim]

I was looking at the 3 output charger thinking to use one output to trickle charge my PowerFrame starter battery. I can save £20 and sort that other ways though. Will have a spare Schaudt 18amp if I parallel the EBL.

Was thinking of bypassing the EBL altogether though. Doing that I can ensure I have lifepo4 profiles on all sources.

would you check the Victron solar chargers for me if you don’t mind, the /30 seems to limit at 290w if panels. Big jump money wise to next up

 

[wildebus]

What I was thinking with the Solar was you could get a cheap set voltage 24V Power Supply for example, and feed that into the Solar instead of the PV Panel (could have a 2-way selector switch) and then use the intelligence of the Solar Controller for 'proper' charging?

As far the Victron MPPTs go, for a 12V system, the /30 supports upto 440W output. the /20 is 290W and the /15 is 220W.
And I agree - a big jump from the 100/30 to the next model up.

PS. With most, and certainly the Victrons, you can have more Panel then the Controller supports. All that happens is that the excess gets chopped off.
So for example, I have a 100/30 Controller (so max of 440W) but I have 460W of panel array. on the very rare occasion it could produce 460W, I will lose out on 20W, but losing 20W 0.01% of the time is better than spending twice as much on the next bigger Controller!

For your Panel, the 100/20 (which is a good saving over the 100/20) would be ideal.

 

[Nabsim]

Think I am going senile, don’t know what I was looking at but it said up to 290W of solar, can’t find it now and as you say it states 440.

Think I have found it, the /20 on onboard energy site is showing 290W is that wrong?

• Maximum PV Panels 290W-12V / 580W-24V

 

[wildebus]

PS. This is the kind of thing I was thinking off with the Solar Controller - https://amzn.to/3ii0QEN
24V 15A Set Voltage Power Supply for £17.
Connect that to a suitable existing MPPT Controller and you could be getting close to 30A/360W for very little money

 

[wildebus]

Think I am going senile, don’t know what I was looking at but it said up to 290W of solar, can’t find it now and as you say it states 440.

Think I have found it, the /20 on onboard energy site is showing 290W is that wrong?

• Maximum PV Panels 290W-12V / 580W-24V

nope, that is right - I remembered wrong (corrected my post now)
if it WAS 330W, it would have had to been a "100/22.5" (half way between 15 and 30 )
For your 300W panel, I would still recommend the 100/20 as the missing 10W will be missing for such little time it is irrelevant.

 

[Nabsim]

Ha ha, that was my thinking with the 250, the days I am losing 50w I have plenty anyway

the 24v psu wouldn’t work with my votronic, max input of 15v. If I went to a Victron with a selector switch would it not matter my panels are 12v parallel then it suddenly swaps to 24v?

 

[Nabsim]

Let’s see if I have it right, if switching 12/24v not a problem.
Go for the Victron 100/30 solar controller, overkill on pu panels but 30 amps mains charge
Fit one of the 24v Amazon PSU units connected to solar charger via switch
Run 24v psu and single EBL charger (or 24v psu alone if sufficient) when little or no solar harvesting.
should give me 40 amp charge from genny with spare capacity

Did I say I hate predictive text lol

 

[wildebus]

Let’s see if I have it right, if switching 12/24v not a problem.
Go for the Victron 100/30 solar controller, overkill on pu panels but 30 amps mains charge
Fit one of the 24v Amazon PSU units connected to solar charger via switch
Run 24v psu and single EBL charger (or 24v psu alone if sufficient) when little or no solar harvesting.
should give me 40 amp charge from genny with spare capacity

Did I say I hate predictive text lol

Sounds about right.
Now I am going caveat something ... I have not tried that kind of solution long-term, but certainly when I was testing out various Solar Controllers, I used a variety of 18V, 24V and 48V Power Supplies like the one I linked to. They run quite hot, so make sure they have cooling available, but the setup always seemed to work - but as the phrase goes ... "buyer beware".

I don't think the controller will care what the voltage is, or that it has changed, as long as it is not greater than 100V, and it also needs to be >5V over the battery (which is why with Lithium, an 18V input may not always be enough to wake it up) (your "12V" Panels will be actually over 20V anyway at times, so pretty close to 24V)
For example, some "12V" Panels .... Left is a Victron 30W panel - Voc is 22.2V; and Right, a Eco-Worthy 100W panel - Voc is 21.6V

Is the Votronic an MPPT or PWM? it sounds like a PWM, in which case you will get a much better harvest anyway by changing.

 

[Nabsim]

My votronic is MPPT, I may be reading it wrong but it says pv Max 20v.
Will check my panels and update this post

My panels Voc is 22.3

this is my solar controllerMPP 250 Duo Digital

VOTRONIC - MPP 250 Duo Dig.

Innovative Elektronik für den mobilen Einsatz

www.votronic.de

 

[Nabsim]

So worse case if it didn’t work I have bought a slightly bigger control than I needed and wasted a cheap psu and selector switch, £25 or so?
Think that may be worth a punt but will just wait and see if anyone else has some ideas. I like lateral thinking