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Charging Battery via Generator and General Advice

Mitter

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Joined
Feb 17, 2022
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Hi there,
To give some background I'm currently running a 320 watt solar panel, a 12v 80ah lead acid battery and the cheapest solar charge controller there is. This system is solely used to run a 4G/LTE router to provide wifi to some wireless Ring cameras that I have placed around the farm to keep an eye on. This has all worked perfectly the past 2 years.

I had someone repeatedly vandalise my field gates and posts over the last few weeks so I now wish to add cameras to the whole perimeter by adding a power over ethernet switch to my current router and running a further 2 routers off that switch. This will use substantially more power - up to 40 watts compared to the 10 it currently is.

I plan to upgrade the battery to a 240ah leisure battery to give sufficient capacity. I'm wondering how it would be best to charge it with a generator if there's not enough solar during bad weather? Ideally I would want the routers to remain connected so I could connect a generator for however many hours it takes whilst still having security.

Finally I have this inverter to run the router https://www.amazon.co.uk/Odoga-Powe...qid=1645095854&sprefix=inverte,aps,215&sr=8-8
It uses 7 watts whilst doing nothing. Is that normal or is it just very inefficient?

Also if anyone has any recommendations as to how I can optimised this I'd be happy to hear.

Cheers
 
A couple thoughts to throw out there:

That leisure battery is FLA which is only good to 50% of it's rated amp hours, so 120Ah usable before you start damaging the battery.

That inverter is going to play holy havoc with your routers and IP cams, get a Pure Sine Wave. As an example, mine at home is a 500w PSW and draws 4w in idle.

Do you need the extra routers to avoid the 100m limit on CAT5? Do you need the router function or can you get away with a simple PoE hub or switch to act as a signal booster for another 100m?

The best way to charge with a generator is to get one of the smarter car battery chargers from the auto parts store. Yes, you lose some efficiency going from AC to DC, but it'll take care of the Float/Absorb/Etc cycles that keep the battery healthy.

Another option to the generator is just getting a second battery and charge one at the house while the other is in the field. A couple clamps can parallel the batteries for longer run time, but when it gets too cloudy just take 1 battery back to the house and charge it up while the other one runs the camera. A couple hours later when it's full go swap batteries. Definitely cheaper than petrol.

Just some noodling for ya. :)
 
I don't think I can do much about the battery unless I throw far more money for a lithium one.

Will order a pure sine wave inverter.

The 2 routers will be going to 2 different corners of the field. I have to have them as Ring cameras have no provision for directly connecting to ethernet. They're wireless only.

If I connect a car charger straight to the battery will that not damage the solar panel or the solar charge controller?

For my current system I have 2 batteries, I just have one fully charged at home ready to swap over when the one in the field cuts out but the 240ah battery weighs 60kg so it's not really practical!
 
I don't think I can do much about the battery unless I throw far more money for a lithium one.
Nope, that makes sense. Just making sure you weren't counting on the full 240Ah out of it. Still good batteries, I use a lot of them at home and camp.
Will order a pure sine wave inverter.
Your electronics will thank you for it. If it doesn't list a standby draw, keep looking.
The 2 routers will be going to 2 different corners of the field. I have to have them as Ring cameras have no provision for directly connecting to ethernet. They're wireless only.
Gotcha. That makes sense. I'm assuming you've got weatherproof enclosures for them already or plans for that?
If I connect a car charger straight to the battery will that not damage the solar panel or the solar charge controller?
Nope! A car charger, another SCC, another battery, it's all the same to a battery. It's very common to parallel charging sources when you've got more panels than a SCC can handle or you're using different size panels that won't play nicely with each other. I do it for my driveway lights at home, I've got a PWM on a 100w, a MPPT on a 208w and sometimes we have to go jump start it with the Jackery and battery clamps. All works together just fine.
For my current system I have 2 batteries, I just have one fully charged at home ready to swap over when the one in the field cuts out but the 240ah battery weighs 60kg so it's not really practical!
Not sure which would have been more hassle to pack out to the field, a generator and battery charger or another battery. Figured I'd throw it out there. :)

All-in-all it sounds like you've got a good basic plan.
 
Well, even 120 Ah, if you draw 3 Ah, are good for some 40 hours, right? For almost a third fourth of which the battery will be under charge... :·)
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Nope, that makes sense. Just making sure you weren't counting on the full 240Ah out of it. Still good batteries, I use a lot of them at home and camp.

Your electronics will thank you for it. If it doesn't list a standby draw, keep looking.

Gotcha. That makes sense. I'm assuming you've got weatherproof enclosures for them already or plans for that?

Nope! A car charger, another SCC, another battery, it's all the same to a battery. It's very common to parallel charging sources when you've got more panels than a SCC can handle or you're using different size panels that won't play nicely with each other. I do it for my driveway lights at home, I've got a PWM on a 100w, a MPPT on a 208w and sometimes we have to go jump start it with the Jackery and battery clamps. All works together just fine.

Not sure which would have been more hassle to pack out to the field, a generator and battery charger or another battery. Figured I'd throw it out there. :)

All-in-all it sounds like you've got a good basic plan.

For the routers I have ordered one of these as I first want to see how much power it actually draws after its connected to 100 metres of Cat5e
https://www.amazon.co.uk/Wireless-W...45103493&sprefix=eap110-outdoor,aps,72&sr=8-3
It's an outdoor model so one less thing to worry about waterproofing.

I have a lightweight pure sine generator https://www.championpowerequipment....=Champion-2500-Watt-Inverter-Generator-92001I
it came with a 12v car battery charging cable and in the manual it says it charges at 8amps. Is it a bad idea to use it? My smart battery charger I use for my car will only do batteries up to 160 amps.
 
it came with a 12v car battery charging cable and in the manual it says it charges at 8amps. Is it a bad idea to use it? My smart battery charger I use for my car will only do batteries up to 160 amps.

That 12v won't fully top off the battery or do any of the Bulk/Absorb/Float stuff that the leisure batteries really like for health and performance, but it will charge it up some. There's no reason your smart battery charger shouldn't work though, I've never heard of one limiting itself on what size battery it can charge.

That's really odd...
 
I run all my networking equipment directly off of a 12 volt battery. It all uses 12v DC anyway, all you would need is a decent DC to DC converter for the POE, and a 12v regulator, rather than a more expensive pure sine wave inverter.

All you would need is a charger that's able to keep up with your loads.
 
I run all my networking equipment directly off of a 12 volt battery. It all uses 12v DC anyway, all you would need is a decent DC to DC converter for the POE, and a 12v regulator, rather than a more expensive pure sine wave inverter.

All you would need is a charger that's able to keep up with your loads.
Hmm this sounds like a more efficient way of doing things.

Would I just run wires straight off the battery terminals into the DC-DC converter? Where would the 12v regulator go?

Sorry I'm a bit rubbish with this...
 
Hmm this sounds like a more efficient way of doing things.
If you don't need AC loads, using an inverter is definitely more inefficient than sticking with DC only.
Would I just run wires straight off the battery terminals into the DC-DC converter?
Yes, and I would add a fuse too. If you're using a lead acid battery, you could get by with regular automotive blade style fuses. Something like this would work.

MCIGICM 12 AWG Inline Fuse Holder with 30A ATC/ATO Blade Fuse, 5 Pack https://www.amazon.com/dp/B081DHT8Y7/ref=cm_sw_r_apan_glt_i_4EAXD9CQGDH0K9WJ621B
Where would the 12v regulator go?
Between the battery and your 12 volt loads. All it does is stabilize your battery voltage (10v-14.6v) into 12 volts. Most equipment could handle the fluctuating voltage no problem, but I don't take the risk with my networking equipment, a $15 regulator (2018 prices ?‍♂️) seems like a small price to pay for peace of mind. This is the one that I use. IIRC, I have the 10 amp version.

Cllena DC 8V-40V to 12V 6A Automatic Buck Boost Converter Step Down/Up Regulator Voltage Reducer Converter Waterproof Regulated DC Power Supply for Golf Cart Club Car LED Light https://www.amazon.com/dp/B08KZSW68...t_i_PA6XFRYM9GNNTRANZYQ8?_encoding=UTF8&psc=1

You also will probably need a step up converter for your POE system, and that would go in the same location as the 12 volt regulator, but would go in front of your higher voltage router. I have one of these for another project.

SMAKN Waterproof DC/DC Converter 12V (10-30V) Step UP to 48V/4A 192W Power Supply Module https://www.amazon.com/dp/B017TPRLLY/ref=cm_sw_r_apan_glt_i_GH5ADTSQ0Z7S15ZS2NEV

Edit: Make sure you check the input voltage on your POE system. My ubiquity stuff uses 24 volts, and I'm pretty sure some of the cameras I have take 48v.
Sorry I'm a bit rubbish with this...
You show all the signs of a good learner.
 
Thank you for taking the time to explain.

Yes I need to wait for the router to be delivered to check the voltage before I can order the converter. I'm guessing you just cut the tip off your router and solder it to the output of your DC/DC converter?
 
Thank you for taking the time to explain.

Yes I need to wait for the router to be delivered to check the voltage before I can order the converter.
What make / model of router is it?
I'm guessing you just cut the tip off your router and solder it to the output of your DC/DC converter?
Yep.
 
As my MR600 is 12v would it be possible to connect it directly to the battery with just a voltage regulator in between?
Otherwise I'd just be converting 12v to 12v?!
 
As my MR600 is 12v would it be possible to connect it directly to the battery with just a voltage regulator in between?
Otherwise I'd just be converting 12v to 12v?!
It would probably run just fine off the battery alone, but long-term it's better to use the regulator. Technically you would be converting a 12 volt battery, which varies between 10v and 14.6v, to an actual 12v.
 
I have a mini pc, modem and router (ap only) all hooked directly to dc12v.

During testing they stayed going down to 10 volts (didn't bother going below that) and have been fine all the way up to 16 volts (equalization via the epever)

The POE switch, just bought a cheap 8 port off Amazon. Removed its power supply and replaced it with 12-to 48v converter.

This has been working fine over a year now. Fingers crossed.
 
I have a mini pc, modem and router (ap only) all hooked directly to dc12v.

During testing they stayed going down to 10 volts (didn't bother going below that) and have been fine all the way up to 16 volts (equalization via the epever)

The POE switch, just bought a cheap 8 port off Amazon. Removed its power supply and replaced it with 12-to 48v converter.

This has been working fine over a year now. Fingers crossed.
Awesome, thank you for posting your first-hand experience. I've never found anybody who successfully ran a router or modem off of a fluctuating voltage for a long period of time (It's not that people weren't successful, there's just not a lot of people doing it or posting.) I had a suspicion that it would probably be okay, but didn't want to test it myself. ?
 
Awesome, thank you for posting your first-hand experience. I've never found anybody who successfully ran a router or modem off of a fluctuating voltage for a long period of time (It's not that people weren't successful, there's just not a lot of people doing it or posting.) I had a suspicion that it would probably be okay, but didn't want to test it myself. ?

I noticed that a lot of devices (not these in particular) say Input: 10-30V DC and use a 12V wall wart power supply.
 
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