Help on 12vlt regulated DC cigarette receptacle

[stormtracker78]

Hi I'm trying to make a 12 volt regulated DC power supply cigarette Jack for a 12 volt refrigerator to run off lead acid batteries or maybe even lithium but I can't seem to find any inverters that have those in them so I was wondering do I need to buy a 12 volt regulator off Amazon and then just wire that on one end to the batteries and the other will have the adapter for the cigarette plug the problem is I can't find any regulators that you can have on load over 10 amps the 12 volt battery is 100 amps so I'm not sure what to do to run my refrigerator I hate to have to buy a jackery or other model due to the amount of money where I can just buy a whole 12 volt 100 amp battery whether it be acid or lithium and somehow just run it directly off that but I would want regulated power any help would be greatly appreciated

 

[Bud Martin]

What is the operating Voltage range of this 12V fridge? What is maximum Amps does it draw?
I would avoid using regulator since you will have some loss unless your fridge really needs tight Voltage regulation.

 

[chrisski]

I found a 400 watt cigarette lighter inverter either at Walmart or a auto Parts store. The cigarette lighter has some sort of limitation to load, and I could not run the inflator I wanted to through the lighter, but hooked the inverter to the battery with the clips also included And that device worked fine.

I’d look at the fuse for the lighter, take the 2/3 of the fuse rating and multiply that by 12, and that may be what a cigarette lighter can provide. That doesn’t include spin up amperage which would take it higher.

 

[stormtracker78]

What is the operating Voltage range of this 12V fridge? What is maximum Amps does it draw?
I would avoid using regulator since you will have some loss unless your fridge really needs tight Voltage regulation.

It's a bouge 12 volt rv type fridge(you can find it on hobotech on you tube)

It runs about 9 amp hours or 120 kw for a 24 hour period so any solar generator that's 300 watts on up can power it for several days especially if it's 500 watts or more the thing is they cost an arm and a leg and I just wanted to run it off the 12 volt DC receptacle because that is way more efficient than the AC inverter you can save up to 100 or so Watts on either Lead or lithium but it needs to be regulated because if not once the battery goes down to a certain point say 50% and that's on lithium like a goal zero it's going to shut off that's the one good thing about the solar generators with a regulated DC 12 volt car adapter receptacle it will continuously put out 12 volts even down to 10% of the battery whereas without it it won't

 

[Bud Martin]

It's a bouge 12 volt rv type fridge(you can find it on hobotech on you tube)

It runs about 9 amp hours or 120 kw for a 24 hour period so any solar generator that's 300 watts on up can power it for several days especially if it's 500 watts or more the thing is they cost an arm and a leg and I just wanted to run it off the 12 volt DC receptacle because that is way more efficient than the AC inverter you can save up to 100 or so Watts on either Lead or lithium but it needs to be regulated because if not once the battery goes down to a certain point say 50% and that's on lithium like a goal zero it's going to shut off that's the one good thing about the solar generators with a regulated DC 12 volt car adapter receptacle it will continuously put out 12 volts even down to 10% of the battery whereas without it it won't

It will a lot more help to provide the model and spec of the fridge instead of trying to get the details info from Youtube. It must have operating Voltage range.
"It runs about 9 amp hours or 120 kw for a 24 hour period" That cannot be right, 9Ah @12V = 108W so for 24 Hours will be 2.592KWh/Day. My 26 cu.ft 120VAC fridge uses about 2.4KWh/day.

 

[stormtracker78]

here's the link regardless of the refrigerator there are a lot of items that need to be run off a 12 volt regulated receptacle I call them cigarette lighter receptacles there might be called a different term so refrigerator or not I need a regulated receptacle that is exactly like in the solar generators there's got to be a way to make one or find one instead of spending five or $600 on a generator

 

[time2roll]

12 volt fridge should tolerate normal voltage fluctuations in a 12v system. I loath those 12v cigar connectors. For something like this I would install some Powerpoles or Anderson connectors.

https://powerwerx.com/anderson-power-powerpole-sb-connectors

If you are dead set on regulating the voltage consider a dc-dc charger.

 

[stormtracker78]

 

[stormtracker78]

Here's a guy who made one for his solar generator I just wanted to make one to hook up to a direct 100 amp battery but the load on the receptacles I think can only take 10 amps here's another video to help you all understand

the power pole would be nice but there's no way for me to go ahead and have a hookup for that for the refrigerator unless I modify something and maybe avoid the warranty I just got the refrigerator 4 days ago it just has a ac plug and then the DC male
to plug into a DC female receptacle so see the basic idea I'm trying to get is to make my own regulated 12 volt DC car receptacle bypassing the solar generator and inverter and just hooking that straight up to 100 amp battery and even if it's lithium with the BMS you still need it regulated as will was saying in his video

 

[Bud Martin]

Do remember this, when the battery is lower than 12V and the regulator is trying to maintain 12V output, the current draw from the battery by the regulator will increase, so as the Battery Voltage gets lower it can trip the battery over current protection.

 

[time2roll]

Go to 2:30 in that video about regulation (post #8). If you are using a lead-acid battery down at 11.6 volts and especially 10.9 volts those batteries are over discharged and will not last long. If you go LFP the voltage stays above 12 volts until very close to BMS cut off so there should not be an issue. If your lead-acid is below 12.2/12.0 volts it needs to be charged.

 

[Bud Martin]

You can just build one like that then if want..
Here is 25A version.

Amazon.com: Cllena DC 8V-40V to 12V 25A Automatic Buck Boost Converter Step Down/Up Regulator Voltage Reducer Converter Waterproof Regulated DC Power Supply for Golf Cart Club Car LED Light: Automotive

Buy Cllena DC 8V-40V to 12V 25A Automatic Buck Boost Converter Step Down/Up Regulator Voltage Reducer Converter Waterproof Regulated DC Power Supply for Golf Cart Club Car LED Light: Power Converters - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[stormtracker78]

Thank you bud didn't know about tripping the battery that's why I love getting all the info from you experts I really do appreciate it ? and thank you for the Amazon link!!

 

[Bud Martin]

Go to 2:30 in that video about regulation (post #8). If you are using a lead-acid battery down at 11.6 volts and especially 10.9 volts those batteries are over discharged and will not last long. If you go LFP the voltage stays above 12 volts until very close to BMS cut off so there should not be an issue. If your lead-acid is below 12.2/12.0 volts it needs to be charged.

+1

 

[Pierre]

On most of these AC/12v DC fridges you have cut out settings on the unit. In the back of my vehicle I run the 50lt
unit , set to cut out at 11,2v , direct from the battery via Anderson connectors. So , just make up a lead with a cigarette socket on the one end and connect the other end directly to the 12v battery. These sockets are available from any car parts store and you don’t even have to solder - get the one with screw type connectors. Your fridge should have built-in fuses on both the AC and DC inputs.

 

[stormtracker78]

Ty! I do have the Anderson power pole connectors and the ratchet I bought from powererx for my shortwave radios and scanners so that way I could use it to wire with the West mountain radio rig runners and such I'm thinking I could combine your idea with Bud's idea and make my own regulated DC 12 volt possibly with a power box or a trolling motor box that has the DC outlet ty again!

 

[mikefitz]

I'm trying to make a 12 volt regulated DC power supply cigarette Jack for a 12 volt refrigerator to run off lead acid batteries or maybe even lithium

Whilst there is lots of advice about regulated supplies, you dont need a regulated supply. The fridge you have will run directly of a vehicle 12v outlet. Its designed to do that. The electronics built into the fridge will compensate for different voltages. The low limit is around 10.5 volts. It can be connected to either 12 or 24 volt batteries, there is auto selection of the working voltages.
The power use numbers you have are incorrect. When the compressor is running it takes around 3 to 4 amps at 12v. Once down to temperature the 'on' period will typically be 25 to 30% of the time. Thus the average consumption is 1 amp per hour at12v, 24Ah per day.

With a fully charged lead acid battery , capacity 100AH, it will be safe to run the fridge for 2 days and draw the battery down to 50%.
In a vehicle there will be no problem running the fridge for long periods whilst the engine is running. When parked it would be advisable not to run off the vehicle battery for more than a few hours.

Mike

 

[stormtracker78]

Thanks Mike but I'm not planning on using the vehicle I bought the fridge is back up in case of a hurricane I live in Brownsville Texas right on the tip South Padre island baby so if we get hit and I'm without power for a couple of weeks or a month or so I need to have some way to have a battery backup fridge that I can take the battery every three or four days and recharge either with solar MPP or what have you so whole issue I'm doing this that's why I DO need a regulated supply so when one battery gets to the low point and shuts off I can switch it over to the other one and then charge the previous battery

 

[Pierre]

Still can’t see the need for a regulated unit. Why don’t you just get a voltage monitor to warn you when the fridge shuts off so that you can switch over to the next battery or automate the whole works so the switching is done for you ? You cannot get a better regulator than a battery.

 

[stormtracker78]

The fridge I have will run 9.2 amp hours or 120wh in a 24 hour period I believe on economy mode or just straight the reason I need that regulated supply is because without it most batteries will shut off the fridge because it's showing low voltage usually around at 50% without the regulated supply with it being used threw the DC receptacle the freezer will not cut off it will keep running because the 12 volts is regulated and constant until the battery is cut off from the regulated suppy which is why I love those solar generators but they cost so much so I'm just trying to make a DYI version and from what I've been studying I'll probably go with lithium if I can get a good deal but even with the lead acids if I use them I'm going to drain them down to 80% because I don't plan on keeping them I'm just trying to get through the hurricane if there is one till the power is back up