How do you hook up back up battery?
|
puckett | how do you hook up a back up bettery? do you just take the power wire from car battery to back up and ground back up? or is there more to it? |
|
New member Username: Motoman22Post Number: 1 Registered: 12-2003 | You'll need a 'Battery Isolator' to let the alternator charge both batteries without letting one drain the other. Check at an RV store...or order one online. Make sure the isolator is rated at least as high as your alternator and use sufficient cable gauge. www.jcwhitneyonline.com has some in the $30 range. |
|
New member Username: GlasswolfPost Number: 67 Registered: 12-2003 | what he said. then one battery will be for starting your car, and the other will be where you wire your audio system or accessories. if the audio system battery is run to zero (ideally you want a deep cycle RG battery for this, like an Optima yellow top) your car will still start from the starter battery which will be "isolated" from the audio system battery circuit. |
|
New member Username: Ukw10Post Number: 5 Registered: 12-2003 | If you put 2 battery to an alternator, do i need better alternator or I could stay with old one that came with my car?? |
|
New member Username: GlasswolfPost Number: 78 Registered: 12-2003 | the alternator will work harder to recharge both batteries while the car is running so any time you add more batteries, you want to upgrade the rest of the charging system to match. here's more info: http://www.bcae1.com/charging.htm and: http://pub14.ezboard.com/fcaraudiotalkfrm27.showMessage?topicID=23.topic I hope that helps |
|
New member Username: Motoman22Post Number: 19 Registered: 12-2003 | CarAudioNewb, It doesn't matter if you have two batteries or twenty, all that matters is the amount of power being demanded by the sum or your electrical system at any particular time. If your electrical system consumes more than your stock alternator produces, upgrade it. If not, roll with what you have. |
|
Anonymous | Does anyone know the CCA rating of the die hard silver car, not truck battery? i have an mx-6 |
|
jay amaro Unregistered guest | michael is right youll need a battery isolator especially if you plan alot of music listening with the car not running and also while your getting that if your going to be mounting the battery inside the car id get a battery box also for mounting and safety. glasswolf also raises a good point and you may want to look into a deepcycle battery and the optima is a good battery i dont think its price is justified eventhough it is a gel cell battery and has a nice design and looks kinda cool unless you have a special need to mount a battery upside down or something it isnt worth the high cost from 150 to 200 typically and any good marine deep cycle battery will do just fine and you can find those anywhere even wal mart. but then againif you want a battery to show off and so people can see it then id say optima would be the right battery. any good boating or rv center should have everything you need but be wary of very high battery mark ups and id get a battery from a retailer that has the ability to do volume buying the small boat/rv dealership doesnt. keepin mind there are only 3 largest battery manufacturers in the world which are exide, gnb and union carbide and most all the batteries for lead acid type are made by one of those 3 companies. so a napa, autozone, energizer, die hard, or whatever store brand name i think walmart calls theirs everlast or something like that but anyways they are all basically the same and pretty much the only differences from brand to brand are the stickers they stick on the outside. thanks, jay |
|
New member Username: GlasswolfPost Number: 379 Registered: 12-2003 | 1: never mount a lead acid battery inside the passenger compartment of a car. Batteries produce hydrogen gas as they warm up. This can KILL YOU. It's a highly toxic gas. If you are going to use dedicated batteries for car audio for use when the car isn't running, you need to stick to RG-grade batteries like Optima's yellow top, which are specifically noted as safe for use in such locations. 2: Deep Cycles are best for this since the hysteresis curve of the batteries for discharge are ideal for this setting. They maintain 12VDC for most of their discharge before falling sharply. here's more info on the different types of car batteries: http://www.wickedcases.com/HT/batteries.html 3: I'm going to disagree here with Jay on the value of the Optima batteries, because they are designed and proven for this exact application, and they are true RG batteries, which means they are safe to use in locations like your trunk or hatchback without producing harmful gases. http://www.optimabatteries.com/faq.asp#q2 As an alternative to Gel cell deep cycles, there are also batteries called Oil cells, which are used by some companies such as Phoenix Gold. final note on batteries, is how they are rated. Many (lesser) companes rate the cold cranking amperes (CCA) of their batteries at room temperature to inflate the numbers. If you want accurate, comparable results, look for batteries rated at 0 deg. for CCA. example is the Sears DieHard Gold battery line. While at room temp, their top model produces 1200CCA. at 0deg., it produces 900CCA. They rate their batteries using both methods, which is nice. For starter batteries, theirs are great, and they stand behind their products. |
|
jay amaro Unregistered guest | hi and first off i hate to touch off a debate although i do enjoy a good one sometimes. i hope not to stepon glasswolfs toes so to speak though by this responce to mounting a battery in a trunk. as for gassing which can happen when any lead acid battery is charged including gel cell batteries such as the optima. the major concern in a relocated or additional battery in the event of gassing is the chance more so of the explosive nature of the hydrogen gas but ill get to that in a second. a lead acid battery is relatively safe to mount in the trunk of a car if its properly ventilated which almost all vehicles do have notonly ventilated trunks usually located in the rear quater panels or floor of the trunk and also cars are positively ventilated when the car is moving to prevent carbon monoxide build up so air is always exchanged and circulated within the cabin of the car. the dangers do exist yes but are very very minimal with gassing becoming a problem in a vehicle and many hot rodders, drag racers, pro street cars and even factory cars such as the BMW M3, X5 and 3301 and ci series all have batteries in the trunk from the vehicle manufacturer with the BMW 330ci a 2004 model car. both www.jegs.com and www.summitracing.com which is where i buy parts for my modified pro street car sell battery relocation kits to mount a lead acid battery in the trunk and to follow nhra guidlines a battery box is to be used also. now keep in mind race cars not mine though because its only a mildly modified pro street car but but top fuel drag cars use a highly explosive fuel mixture of nitro methane that would make gasoline look like water and that is stored in a fuel cell in the trunk of the car along with a battery or 2 in the trunk also and this has been done for many years using regular lead acid batteries before there was a battery such as optima on the market and the trunk mounted battery was used safely not only by myself and many other pro streeters, bracket racers, dragsters, circle track cars and also the factory BMW's and cars that have hydraulic systems or the street term of "bounce kits" all those applications with the BMW's withheld put the vehicle, rider and battery under extreme conditions with very little battery related issues of gassing and potential explosion. as long as certain conditions are met such as: the connections are good tight connections to the battery, a well regulated charging system to not over charge any battery and the area of the battery is well ventilated it is not dangerous to have a battery in the cabin of a car however the trunk is even more ideal but those who have hatchbacks should have very little problems as well but i do think marginally the trunk is a safer place. some other applications of where a battery would be found inside the confines of people would be in military applications such as armored personnel carriers, tanks, underwater vessels, planes and in the common household if anyone uses an UPS system which i have 2 large ones and a smaller one and my 2 large ones are APC UPS model 1400VA and each carry 12V 1400 ah and the smaller one is a 12V 7 ah rating and they all 3 reside on my computer desk right beside me however while i have no doubt they are subject to gassing and give off hydrogen gas because of direct ventilation into the room it poses no danger. extensive military testing has been done on this subject and it was determined the effects of gasing are also reduced by time. here is an excerpt from a military spec'd test: "After 2 years of use the above values reduce by a factor of 10. Trials conducted on sealed lead-acid batteries 30 V 130ah VG 96 924 T 05 subjected to specific 19 hours recharging at a constant charging voltage of 2.37 V/cell demonstrate that: During the charging operation the following amounts of gas escape from the complete battery assembly: New battery assembly: 10 liters After 10 charge-discharge cycles: 4 liters After 150 charge-discharge cycles: 1 liters The above is from Sealed lead-acid batteries / Military Applications" if a battery is over charged, charged with too high a voltage and is unventilated then those can create dangerous conditions however to reach the lower limit of 4% and the explosive 6% limit of hydrogen gas would be 60,000 ppm and long before a boiling battery would reach gaseous toxic levels and worse explosive levels the hydrochloric acid which is sulfuric acid would produce noxious fumes that would be very much a warning sign to anyone in a vehicle and the hydrogen gas alone would be undecernable yes but that wouldnt happen and during the normal charging process a small amount of hydrogen gas is released but the amount is very small and due tothe trunk and cabin always having positive ventilation it should not be a concern and i am sorry i hope not to offend you glasswolf i have read many of your posts and i respect you and your knowledge and truly mean no offense to you. you information is very true and necessary about CCA and its importance in choosing a good battery or more importantly a battery that will provide enough amperage. i understand and support your endorsement of the optima batteries and they are good batteries i have no doubt of that i just wouldnt want someone to think they need to spend a couple hundred dollars when a battery in the 40-60 range or so would work just as fine. but i will concede this if anyone has any reservations or even worse are considering the undertaking of mounting a battery in the trunk and do not posses the knowledge and understanding of a cars electrical system then this should be a project left to a mechanic and for the best safety margin an optima battery might also be something to look into. hope everyone has a good new years and thanks, jay |
|
New member Username: GlasswolfPost Number: 405 Registered: 12-2003 | " properly ventilated which almost all vehicles do have notonly ventilated trunks usually located in the rear quater panels or floor of the trunk and also cars are positively ventilated when the car is moving to prevent carbon monoxide build up so air is always exchanged and circulated within the cabin of the car." in some cars yes, but more and more those trunks are sealed off like fort knox. GMs are a good example with cars like the Impala, and Monte Carlo, where you (the installer) need to ventilate the rear deck of the car just so bass can get through if you mount the sub enclosure there.. otherwise it's overly muffled, and doesn't work very well. Anyway while some or even "most" cars may have a negative pressure environment to force air flow (which is great if it's tehre and it works) most custom installs end up blocking ventilation points and re-doing teh trunk interiors when you get to the level of battery banks, and custom fit sub boxes and amp racks, so in a "non-ideal" setting, which is what I try to assume is the case unless I know otherwise (to be safe) it's wise to at least point out the issue of gassing, as well as the explosive nature of batteries. Mainly just because the average Joe won't consider that or be aware of it unless he's told by someone like us.  I always try to err on the side of caution till I'm sure the person knows what he's doing. In regard to BMW, Mercedes, et al who place a factory battery in the trunk, the trunk is then designed for such, and ventilation is a factor in the car's design. We're talking aftermarket mods here though. We do the fabricating to make it work right. That's why it helps to be an engineer As for street rods, I work on a pro street car that a local team runs. Keep in mind most of these cars also use fuel cells which put the gas tanks right behind the driver. Safety isn't the key factor, though it's part of the rules in design. When you talk race cars, they rarely have side windows at all, so venting isn't a problem haha they also have vented body panels and such which make them a vertiable wind tunnel inside.. (the car we run is an 82 Camaro with a normally aspirated 468CID motor, balanced and blueprinted running pure alcohol. tubbed, full cage, cells, gutted, etc.. it's a fun toy.) yes I have some UPSs as awell, and if you've ever seen those batteries, I can hold one in the palm of my hand. They aren't the same size as the ones in a car, nor are they in as confined an environment. keep in mind the main factor here is that we're talking deep cycle batteries that are there for the sole intent of being run into the ground, then fully recharged, then run down again. they'll be run hard, which means their duty cycles will be extreme, leading to a higher probability of gassing, or expanding and splitting the casing of the battery (which is what happened to the batteries that ran our demo boards at the shop where I worked on occasion) I agree the Optima is ideal as a second battery, dedicated for an audio system. I wouldn't suggest a yellow top as a starter battery. quite frankly they suck for that.. low CCA, but they are perfect for an isolated audio system supply, given you have the alternator to match when the car is actually running. I think we agree really, it's just a matter of how severely you wish to interpret the danger. I may have overstated that point, but I didn't want it brushed aside by those who don't happen to possess an E.E. degree, as some of us do. |
|
jay amaro Unregistered guest | hi glasswolf and yeah there are always variables and i think yeah maybe thats what it is we were coming from 2 different standpoints on this and ultimately safety should be the main concern. yeah i certainly wouldnt recommend and amateur jump into messing with the charging system but for the most part in a typical application it is reasonably safe for the audio enthusiast or weekend racer to mount a battery in the trunk of a car or truck for their stereo or for handling reason and better weight distribution but yeah a highly customized audio user should pay even more attention to ventilation especially if they have changed the natural ventilation of the vehicle. i guess thats that and now moving along yeah my small ups is a fairly small batt but the 2 1400va ups each have 2 batteries about the size of a garden tractors batery but then again they each give me about 45 to an hour of backup power time. but they are highly regulated charging systems and emissions are very low from that. well i hope what everyone got out of that is just please make sure you have adequate ventilation if you move the battery and if your uncertain then go with optima just to be on the safe side. that camaro sounds interesting and ill bet its alot of fun on the track. my daily driver is a 1986 iroc z28 with t-tops and a slightly modified motor and slightly modified audio system (sony mobile es deck, sony 10 disc changer, sony 6x9's and infinity 4x6's, rockford punch 45, rockford punch 150, bazooka rs8a-hp, rockford fosgate hx2 rfr3110 in a sealed box where my spare tire used to be). i have a tuned port injected 350 with a few mods but am currently building a new motor for it due to the fact ive been getting some close runs from some imports i decided to pull out all the stops and the soon to be replacement will be a small block 400 with gasket matched vortec heads with 1.6/1.7 rockers and a lunati roller cam. im building it for about 450-500 horses on the motor and 200 more on the bottle and with slicks on the track it should get me 10's i hope. ive never been beat by an import yet but why take any chances :D but anyways i always look forward to your posts and have a good new years everyone. jay |
|
New member Username: GlasswolfPost Number: 416 Registered: 12-2003 | yeah the Camaro is fun.. if it weren't winter already up here I'd get some pictures of it.. it's a gorgeous electric blue, and the motor is entirely chromed. We do a lot of shows with it sine the owner (friend of mine) mainly collects cars. anniversary firebirds, vettes and stuff like that. on the subject of ventilation, sedans with trunks usually aren't the big thing I worry about, but things like hatchbacks, and trucks where there's really no saparation for the passengers and the batteries.. in those cases if one of the batteries does go bad, there isn't much between you and all that mess. |
|
Unregistered guest | guys i need desperate help...i have a bmw 320i 2004 model...i installed a rockford fosgate amp which is connected to 2 10" rockford subs...i did the same thing to my 2003 bmw 320i and because of tat i had this stupid engine light came on, and some transmission problem too (starts off on the 4th gear, starts really slow..)...the guy who chekced out the car said tat the battery provides certain power all over the car...and cus of the amps its giving those problems....now i jsut installed the subs in my 2004 which i got a week back and same freakin problem...WHAT CUD BE THE PROBLEM...PLEZ HELP ME ANYONE |
|
Anonymous | You prolly need a BIGGER alternator. Try a 150-200amp alternator. |
Main Forums
Today's Posts- Home Audio Forum
- Home Video Forum
- Home Theater Forum
- Car Audio Forum
- Accessories Forum
- All Forum Topics