Wiring two batteries in one car?

[///M5 2,833]

With a 110 amp alt you should be ok with an extra batt like you mentioned. Definitely get a voltage meter and hook it up at the amps power supply so you can monitor voltage at the amp.

If you truly have to "monitor" your voltage I'd suggest turning your gains down or upgrading your alt. Being in a situation where monitoring is required isn't acceptable.

[Angelboy863 21]

What I'd like to know is will having two batteries make the alternator work harder? I don't plan on bumpin with my car off so as long as the car is running, the alternator should provide power to my batteries if needed? And do you guys recommend isolators and relays

[Angelboy863 21]

With a 110 amp alt you should be ok with an extra batt like you mentioned. Definitely get a voltage meter and hook it up at the amps power supply so you can monitor voltage at the amp.

If you truly have to "monitor" your voltage I'd suggest turning your gains down or upgrading your alt. Being in a situation where monitoring is required isn't acceptable.

I'm going to get the volt meter otherwise. I just would like to know my volt level while I'm bumpin which I really hope won't be low with this setup I'm trying to figure out

[Tremonic 7]

A voltage meter is always recommended. I don't forsee you having any issues with what your going to be running. A meter is just a safeguard so if something fails ( alt, battery etc) you'll see the drop and not just keep on jamming and possibly hurt something. It's not really so you can sit there and watch it 24/7. And no, you don't need a relay or isolator unless you plan on jamming with the car off.

[pmureika 31]

Many cars come with a vollt meter.If not run it from the back battery.

[Angelboy863 21]

Alright everything isstsrting to sound good lol. The batteries I plan to get are the shuriken 1500 cranking amp battery for my starter, and for the rear the shuriken 850 cranking amps. Will those batteries do it? I don't know much about battery power.

[Angelboy863 21]

And what fuse size do you guys recommend? I will be running 1/0 wire to everything and it's a 1500 RMS amp and the batteries are 1500 cranking and 850 cranking. Thanks

[Tremonic 7]

1/0 is good for 300 amps so fuse it for that. On the wire going to your amp you'll fuse it to whatever the recommended fusing is for the amp. As far as batteries go the AH rating is what you want to look for. CCA doesn't mean anything in this application. You'll want a batt with a rating of about 100AH.

[Angelboy863 21]

Ok.. So what if my batteries both have a AH rating below 100? Is it bad to get em a bigger fuse my main one is 60AH and my rear battery is 20AH.

[Tremonic 7]

You don't fuse for the batts, you fuse for the wire. 1/0 will handle 300 amps so you want 300 amp fuses everywhere except on your amps power wire coming from the rear batt. Those batts will probably struggle trying to keep up with that load but there's only one way to tell. Throw it in there and see what it does before you invest in a different batt. You may find that you don't even have any issues. But yeah the fuse isn't going to determine the output of the batts

[Angelboy863 21]

Shit. I was trying to keep a low budget ya know? But I don't want any type of questioning about my batteries so I'll upgrade to bigger cranking. Like 2250 and a 1900

[Tremonic 7]

Remember in this application the AH rating is what your looking for.

[///M5 2,833]

A voltage meter is always recommended.

Meh. I'd rather have an oil pressure gauge and a few other gauges first.

And just like oil pressure "should" always be in range when your car is setup right, your voltage should be as well when you build a system otherwise you should fix that problem.

[Tremonic 7]

A voltage meter is always recommended.

Meh. I'd rather have an oil pressure gauge and a few other gauges first.

And just like oil pressure "should" always be in range when your car is setup right, your voltage should be as well when you build a system otherwise you should fix that problem.

Well I dunno, maybe everyone can't afford to do everything perfect the first time? He has a plan. What's so wrong about having a voltage meter? I mean if we're thinking like that then you know your engine is in pretty good shape right? Well then just go ahead and disconnect all of your gauges then because you know it's done right correct? So just like you said you shouldn't have to monitor it right? There's nothing at all wrong with watching your voltage. Every proffesional setup has a meter no matter what they have invested because it's a good idea, plain and simple. In the end he's going to get his setup done correctly and then he can sit back and watch his voltage stay nice and steady with a smile.

[BanginGMC 23]

A voltage meter is always recommended.

Meh. I'd rather have an oil pressure gauge and a few other gauges first.

And just like oil pressure "should" always be in range when your car is setup right, your voltage should be as well when you build a system otherwise you should fix that problem.

Well I dunno, maybe everyone can't afford to do everything perfect the first time? He has a plan. What's so wrong about having a voltage meter? I mean if we're thinking like that then you know your engine is in pretty good shape right? Well then just go ahead and disconnect all of your gauges then because you know it's done right correct? So just like you said you shouldn't have to monitor it right? There's nothing at all wrong with watching your voltage. Every proffesional setup has a meter no matter what they have invested because it's a good idea, plain and simple. In the end he's going to get his setup done correctly and then he can sit back and watch his voltage stay nice and steady with a smile.

x1000000000000000

and i'm sure 95% of the people here will agree as well, having a voltage meter in your car is a very nice tool.

[Angelboy863 21]

True. I've figured out what I want to do. Thanks everyone.

[Luke.H 33]

Well I dunno, maybe everyone can't afford to do everything perfect the first time? He has a plan. What's so wrong about having a voltage meter? I mean if we're thinking like that then you know your engine is in pretty good shape right? Well then just go ahead and disconnect all of your gauges then because you know it's done right correct? So just like you said you shouldn't have to monitor it right? There's nothing at all wrong with watching your voltage. Every proffesional setup has a meter no matter what they have invested because it's a good idea, plain and simple. In the end he's going to get his setup done correctly and then he can sit back and watch his voltage stay nice and steady with a smile.

Its a little different than an engine. If you build up your electrical the way you should it shouldn't drop to unsafe levels and it should stay that way. If you can't afford to power an amp correctly then don't buy that amp, buy a less powerful amp or run less power until you have the electrical to support it. If you have to constantly monitor your voltage you have a problem. Not to mention I find a bright blue meter aesthetically displeasing...but that's irrelevant. Competition use is a different story. I assume that's what you meant by professional.

Edited June 15, 2011 by theluker69

[///M5 2,833]

A voltage meter is always recommended.

Meh. I'd rather have an oil pressure gauge and a few other gauges first.

And just like oil pressure "should" always be in range when your car is setup right, your voltage should be as well when you build a system otherwise you should fix that problem.

Well I dunno, maybe everyone can't afford to do everything perfect the first time? He has a plan. What's so wrong about having a voltage meter? I mean if we're thinking like that then you know your engine is in pretty good shape right? Well then just go ahead and disconnect all of your gauges then because you know it's done right correct? So just like you said you shouldn't have to monitor it right? There's nothing at all wrong with watching your voltage. Every proffesional setup has a meter no matter what they have invested because it's a good idea, plain and simple. In the end he's going to get his setup done correctly and then he can sit back and watch his voltage stay nice and steady with a smile.

I never said not to measure it, but was helping the OP save money on the build as the value of mounting one permanently I see as not necessary. By your argument then the other gauges should also be added and in that regard first as the cost to replace the other items is more than the parts that low voltage will cause.

Using a gauge as an excuse to turn the levels up to where the gauge is necessary to monitor it is asinine. As I stated before, measure it and set the gains right for the electrical that you have. If there is an issue, don't push the limit.

[BanginGMC 23]

A voltage meter also lets you know if something is wrong, lets you know when to back down and let your batts recharge a minute. If you start your car and the voltage is at 13.5 you know something happened, something bad.. if you didn't have a voltage meter, you wouldn't know. It'll let you know if your batterie(s) took a shit due to manufacture defect.

If your going to spend thousands on an system, and try to save money by not getting a 20 dollar voltage meter, that is just plain fail.

[Tremonic 7]

Well I dunno, maybe everyone can't afford to do everything perfect the first time? He has a plan. What's so wrong about having a voltage meter? I mean if we're thinking like that then you know your engine is in pretty good shape right? Well then just go ahead and disconnect all of your gauges then because you know it's done right correct? So just like you said you shouldn't have to monitor it right? There's nothing at all wrong with watching your voltage. Every proffesional setup has a meter no matter what they have invested because it's a good idea, plain and simple. In the end he's going to get his setup done correctly and then he can sit back and watch his voltage stay nice and steady with a smile.

Its a little different than an engine. If you build up your electrical the way you should it shouldn't drop to unsafe levels and it should stay that way. If you can't afford to power an amp correctly then don't buy that amp, buy a less powerful amp or run less power until you have the electrical to support it. If you have to constantly monitor your voltage you have a problem. Not to mention I find a bright blue meter aesthetically displeasing...but that's irrelevant. Competition use is a different story. I assume that's what you meant by professional.

I understand what your saying but hey, your oil pressure SHOULDN'T drop in your car but you still have a gauge. Your temperature SHOULDN'T ever go over the optimal range but you still have a gauge. It's just like anything else it's good to have it to keep an eye on it. If you read my earlier post I stated that it's not there for him to stare at and walk the fine line. The setup he is going to put in should support what he's looking at running with no problems but what if his alt fails? What if a batt shorts? I mean I honestly can't believe that you guys would argue the point of having something like a meter. And your reference to a motor? No it's not so different. It's a tool to monitor what's going on just like any other gauge you have in your car.

[Angelboy863 21]

you guys are all making great points and i commend you on that. but in the end, i will buy a volt meter, just to be safe. i am on a budget, and fuckin up a alternator or a battery because i didnt know how it was running (volt meter) sounds like not so smart of an idea.

i know, i shouldnt have to have the volt meter if im well aware that my system will be ok. if i did upgrade my alternator, i probably wouldnt get a volt meter. but because i do have some doubt of my electrical system, im going to have one just in case. and im not building for competition purposes, no way. i just want a little bump with a little bit more power than normal. and again this is my first build, so its nice to hear opinions on both sides, i just keep gaining knowledge as i read. thanks guys!

[Luke.H 33]

Well I dunno, maybe everyone can't afford to do everything perfect the first time? He has a plan. What's so wrong about having a voltage meter? I mean if we're thinking like that then you know your engine is in pretty good shape right? Well then just go ahead and disconnect all of your gauges then because you know it's done right correct? So just like you said you shouldn't have to monitor it right? There's nothing at all wrong with watching your voltage. Every proffesional setup has a meter no matter what they have invested because it's a good idea, plain and simple. In the end he's going to get his setup done correctly and then he can sit back and watch his voltage stay nice and steady with a smile.

Its a little different than an engine. If you build up your electrical the way you should it shouldn't drop to unsafe levels and it should stay that way. If you can't afford to power an amp correctly then don't buy that amp, buy a less powerful amp or run less power until you have the electrical to support it. If you have to constantly monitor your voltage you have a problem. Not to mention I find a bright blue meter aesthetically displeasing...but that's irrelevant. Competition use is a different story. I assume that's what you meant by professional.

I understand what your saying but hey, your oil pressure SHOULDN'T drop in your car but you still have a gauge. Your temperature SHOULDN'T ever go over the optimal range but you still have a gauge. It's just like anything else it's good to have it to keep an eye on it. If you read my earlier post I stated that it's not there for him to stare at and walk the fine line. The setup he is going to put in should support what he's looking at running with no problems but what if his alt fails? What if a batt shorts? I mean I honestly can't believe that you guys would argue the point of having something like a meter. And your reference to a motor? No it's not so different. It's a tool to monitor what's going on just like any other gauge you have in your car.

That wasn't really the point I was making. I'm saying you shouldn't push your equipment to the point where monitoring your voltage is necessary. If you want it to monitor equipment failure far be it from me to stop you. Whatever makes you feel comfortable

Edited June 15, 2011 by theluker69

[An-i-no 86]

Well I dunno, maybe everyone can't afford to do everything perfect the first time? He has a plan. What's so wrong about having a voltage meter? I mean if we're thinking like that then you know your engine is in pretty good shape right? Well then just go ahead and disconnect all of your gauges then because you know it's done right correct? So just like you said you shouldn't have to monitor it right? There's nothing at all wrong with watching your voltage. Every proffesional setup has a meter no matter what they have invested because it's a good idea, plain and simple. In the end he's going to get his setup done correctly and then he can sit back and watch his voltage stay nice and steady with a smile.

Its a little different than an engine. If you build up your electrical the way you should it shouldn't drop to unsafe levels and it should stay that way. If you can't afford to power an amp correctly then don't buy that amp, buy a less powerful amp or run less power until you have the electrical to support it. If you have to constantly monitor your voltage you have a problem. Not to mention I find a bright blue meter aesthetically displeasing...but that's irrelevant. Competition use is a different story. I assume that's what you meant by professional.

I understand what your saying but hey, your oil pressure SHOULDN'T drop in your car but you still have a gauge. Your temperature SHOULDN'T ever go over the optimal range but you still have a gauge. It's just like anything else it's good to have it to keep an eye on it. If you read my earlier post I stated that it's not there for him to stare at and walk the fine line. The setup he is going to put in should support what he's looking at running with no problems but what if his alt fails? What if a batt shorts? I mean I honestly can't believe that you guys would argue the point of having something like a meter. And your reference to a motor? No it's not so different. It's a tool to monitor what's going on just like any other gauge you have in your car.

That wasn't really the point I was making. I'm saying you shouldn't push your equipment to the point where monitoring your voltage is necessary. If you want it to monitor equipment failure far be it from me to stop you. Whatever makes you feel comfortable

Eh...you guys are making it too crucial. The volt meter is pretty necessary when doing any kind of electrical upgrades. Not only for LOW voltage but voltage spikes and other oddities. And plus, how the heck would you know how much is too much without the volt meter? Sure his lights might dim but if he's at 13.5+ all the time then he doesn't need to back off the gain/volume. Once again, without a volt meter he doesn't know that.

Sure if you never spend more than you make you'll always have money right? But does that mean you should never look at your bank statement?....like seriously? We're talking about a nice 20 investment. Could be much cheaper.

[///M5 2,833]

If you truly have to "monitor" your voltage I'd suggest turning your gains down or upgrading your alt. Being in a situation where monitoring is required isn't acceptable.

This was the basis for this discussion and the statement is the most important one here.

Never did I state not to use a gauge, but it is no more important than other gauges. If you "have" to watch a gauge it means you are expecting a failure. I personally would make sure the design is such that you don't expect one and is a much better idea than monitoring it to make sure. As for the protecting the thousands you spend on a system, there are other more expensive repairs that can happen as well. Does everyone monitor their transmission temp, engine oil pressure, gas/air mixture and so on? Any one of those systems failing is surely going to create more expense than an undervoltage on an amplifier. So which do you add first? If you answer any other way than the one you expect to most likely fail your answer is idiotic. If you design your system such that you create the voltage scenario as the one most likely to fail, I'd change your design before adding a meter which was my original point.

So yeah, meh on blindly recommending a meter. Install/design the system correctly instead.

[pmureika 31]

If you truly have to "monitor" your voltage I'd suggest turning your gains down or upgrading your alt. Being in a situation where monitoring is required isn't acceptable.

This was the basis for this discussion and the statement is the most important one here.

Never did I state not to use a gauge, but it is no more important than other gauges. If you "have" to watch a gauge it means you are expecting a failure. I personally would make sure the design is such that you don't expect one and is a much better idea than monitoring it to make sure. As for the protecting the thousands you spend on a system, there are other more expensive repairs that can happen as well. Does everyone monitor their transmission temp, engine oil pressure, gas/air mixture and so on? Any one of those systems failing is surely going to create more expense than an undervoltage on an amplifier. So which do you add first? If you answer any other way than the one you expect to most likely fail your answer is idiotic. If you design your system such that you create the voltage scenario as the one most likely to fail, I'd change your design before adding a meter which was my original point.

So yeah, meh on blindly recommending a meter. Install/design the system correctly instead.

He needs to blow a few subs and amps before he learns.like my nephew.