Can I wire AC-DC Charger to bus bar instead of direct to battery?

TommyinMiami

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Thanks for all the replies and help so far. Everything is basically wired up now. I have not tested all components yet though. I just want to make sure...
My 10Amp AC-DC charger is hooked in to my neg and pos bus bars. When I turn on the charger the current wont flow to my solar panels or anything else coreect? it will find its way to the battery? Basically everythng is hooked on the bus bar.

When I turned the system on I got voltage flowing through my DC-DC charger. I thought it would only go out the other side when a 12v ignition wire is attached. I wired the ignition activating wire to the 12v input jumper cable terminals so I could backup charge my system from my truck. It would sense the 12v connection from the jumper cables and then turn on. but Voltage is 12v on the inputs and the outputs on the DC-DC so I guess that won't work and I need to wire a switch to turn on to activate the charger. Not what I was expecting but ok.

I took the advice of you guys and I am upgrading to 4/0 wires. I already used 4/0 for my parallel connections and will change my 2/0 inverter wires to 4/0 today

I'm using a Renogy Rover 40Amp controller with BT. Im surprised to see there is no wifi network device only 4G module or BT. I wish they made Wifi then I could still log in anywhere I am to check on my values. Don't need 4G cell module to do that, but I guess Renogy is a little behind the times.
Ill put up some pics. I may have gone a little overboard.
2022-04-10 19.19.13.jpg2022-04-10 23.44.56.jpg2022-04-10 21.33.25.jpg2022-04-10 23.43.50.jpg2022-04-10 23.42.11.jpg
 

rmaddy

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When I turn on the charger the current wont flow to my solar panels or anything else coreect? it will find its way to the battery?
Electricity is pulled to where it is needed. It is not pushed. So you don't need to worry about charging your solar panels. :)
 

TommyinMiami

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Oh last Q. I have 2 more batteries on the way to give 400 amp hours total of LI. When you connect 4 batteries in Parallel you connect to the system in one of the middle 2 batteries? Is that correct? They all have internal BMS's.
 

rmaddy

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Have a look at chapter 3 of the Wiring Unlimited book for a great explanation on connecting batteries in parallel.

 

TommyinMiami

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Have a look at chapter 3 of the Wiring Unlimited book for a great explanation on connecting batteries in parallel.

Woah! Thank you! Awesome guide. Thanks so much.
 

BIGFOOT

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Hi guys, brand new here, long-time lurker. I am building a DIY gen and had a quick question. I am trying to keep my install cabinet as clean and simple as possible.

I am wiring up an AC-DC 10amp NOCO charger to the system for when the unit is in storage. Can I wire this directly to the fused pos and neg bus bars instead of wiring it directly to the battery terminals with inline fuses?

It's only a 10amp charger, 15Amp fuse. Nothing will be used when this is charging. No panels attached, no loads, nothing to confuse the charger.
Thank you for any help, advice, or suggestions

Usage: Only as battery backup for hurricanes (Miami), no grid tie-in, Prepper purposes, occasional use working on the boat and needing AC tools.
Everything is tinned copper because I live next to the ocean and will occasionally use it on the boat.

System:
Cabinet - Bottom half of Home Depot Husky Rolling Tool Chest after draws removed
GoWise 3,000/6,000 Watt Pure Sine Inverter (300A MEGA fuse)
Renogy 40Amp Charge Controller (40A & 30A ATC fuses)
Renogy 40Amp DC-DC Charger (50A & 60A ANL fuses)
2 direct pos neg attachment points to connect to car alternator to DC-DC charger for emergency backup charging
Renogy Battery Monitor and 500Amp Shunt
Renogy Bluetooth module
45A Anderson Power pole hookup, 1 30A Power Pole connection
6 waterproof AC outlets
1 High Amp AC outlet
1 500A Total System On/Off disconnect switch (for everything except inverter)
1 125A Blue Sea Marine 12 circuit fuse pannel with neg bus
2 ACguys variable power, 120mm cooling fans
1 ACguys Thermostat fan controller
1 NOCO LiFePo4 10Amp AC-DC Charger (15A ATC fuses)
1 NOCO AC passthrough connector to attach AC power to NOCO AC-DC charger
6 USB Chargers 3 USB-C Chargers, 2 12-volt outlet connections
4 soft white 3,000k 12 volt lights to provide ambient room lighting
4 100watt 12v Rich Solar panels
1 Weize 100Ah 12v LiFePo4 battery (planning to add 3 more in the future to have 400Ah total.
2/0 Battery to inverter wires 24" length and 2/0 Battery to Battery wires. 12" length
and Finally, 1 12v rope lighting inside the cabinet for "cool factor" and I guess to see components while working on them.

View attachment 89637
Do you have a bus bar for high amp's 450 - 500 amps (that I'm not seeing) to connect too? If so yes.... don't run it though the DC fuse box (bottom right of your picture).
 

timselectric

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Do you have a bus bar for high amp's 450 - 500 amps (that I'm not seeing) to connect too? If so yes.... don't run it though the DC fuse box (bottom right of your picture).
It's only a 10a charger.
 

12VoltInstalls

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how do you know when you need a fuse on both the positive AND negative wire?
I always thought you only needed a fuse on the + wire, but my NOCO AC-DC charger has a fuse on both the + and -, and the wires coming in from the anderson connection also have a fuse on the + and the -. Is that always needed, or is it an extra redundant safety mechanism?
If the LARGE capacity batteries or even solar input has a bad moment a fuse on neg(-) could stop things from looking for ground through the little baby noco charger is what I’d guess. The idea of positive grnd protection I guess makes sense but electrons are still going to transfer energy in the same direction so I dunno.
I wired quite a number of genius chargers on utility trailers and never had two fuses but that was a few years ago
 
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Zil

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If the LARGE capacity batteries or even solar input has a bad moment a fuse on neg(-) could stop things from looking for ground through the little baby noco charger is what I’d guess. The idea of positive grnd protection I guess makes sense but electrons are still going to transfer energy in the same direction so I dunno.
I wired quite a number of genius chargers on utility trailers and never had two fuses but that was a few years ago
On one of my old vehicles, during starting, the small braided wire that connected the firewall to the engine block melted and fired up some grease when the main cable connection from the battery failed at the engine block.
 

12VoltInstalls

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fired up some grease when the main cable connection from the battery failed at the engine block.
You should see what happens sometimes in a jeep when people ground their winches through the frame! 🔥 It will find a voltage differential somewhere- even the pos(+) connected PDC- and something will catch on fire.
 

BIGFOOT

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It's only a 10a charger.
Your battery connections should be attached with a bus bar.... you have a 12v battery with more than 10a battery right? This is where the bus bar should be more than your battery. ANL fuse from battery to bus bar on POS size... shunt on NEG side for meter..... Heavy bus bar 450a up! Your DC fuse box should be fuse and run off your bus bar also...
 

TommyinMiami

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I'll send a pic of the sides, that's where the DC-DC is (left side, not left back)
Its 12v. Batteries are 100a total if 1 internal bms failed.
The AC-DC is only 10a
The DC-DC charger is 40a (installed only as backup to solar)
DC-DC charger has 50a in and 60a fuse to battery. (Both are out right now) I wired the 12v activation wire to the stud jumper cables would attach to, the idea was the 12v from cables would activate the charger BUT it gets 12v from my system so I need to wire in a switch or run a hardwired special cable that connects to this lead only when hooked up to a car. I'll prob just do a switch. I guess I somehow thought when the charger was not in the output side wouldn't have voltage but I guess that was stupid thinking.
The Buspar is 150a max has dedicated 100a fuse all blue sea
The fuse panel is 150a also has its own dedicated 100a fuse blue sea
The inverter is not grounded to frame or ground rod. (Does it need to be) it has dedicated 250a master fuse (direct to battery)

Do I need to up the amps of my bus bars. 4/0 wire to batteries now. 4/0 between batteries.
Charge controler has 40a fuse

Thank you guys for all advice. My wife and 2 dogs appreciate me not burning down the house also. :) I'll help is MUCH appreciated.
 

timselectric

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Your battery connections should be attached with a bus bar.... you have a 12v battery with more than 10a battery right? This is where the bus bar should be more than your battery. ANL fuse from battery to bus bar on POS size... shunt on NEG side for meter..... Heavy bus bar 450a up! Your DC fuse box should be fuse and run off your bus bar also...
The OP wanted to know if it was ok to connect his 10a charger to the bus bars.
Answer: yes
And, he could connect it to the fuse box. Without any problems, either.
 

12VoltInstalls

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The inverter is not grounded to frame or ground rod. (Does it need to be) it has dedicated 250a master fuse (direct to battery)
I’m an advocate of case-grounding mobile inverter installations to the frame as that is a conductor with certain faults- and will trip a breaker or blow a fuse. Some inverters are case-grounded to their neg(-) battery terminal I have heard it said but I’ve not seen that. Usually there’s a lug or stud for this.
 
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