Anyone hide a digital voltmeter?
#1
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Car: 1986 Firebird
Engine: 2.8 V6
Transmission: 700R4
Anyone hide a digital voltmeter?
If so, just wondering where you might've hidden one. I realized last week (after hearing of a friend whose battery died) that I have no way of knowing, other than the alternator light, if my battery's dying. It'd be nice, I think, to have a hidden gauge to show me voltage.
Either that or I thought of wiring up an LM339 comparator circuit to show me if battery voltage dropped below a certain setpoint, and light up a BFL (big freakin' LED) if it did. But that wouldn't be as helpful as a gauge would be.
Either that or I thought of wiring up an LM339 comparator circuit to show me if battery voltage dropped below a certain setpoint, and light up a BFL (big freakin' LED) if it did. But that wouldn't be as helpful as a gauge would be.
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Car: 88 Iroc-Z
Engine: 355ci
Transmission: WC-T5
he wants a digital gauge showing the voltage of his batery.. like a gauge that says air/fuel ratio.. instead it would be voltage the battery has
#4
TomP - I am assuming by your information that you do not have the full gauge cluster. What about swapping in the full cluster? You can get them pretty cheap at the wreckers.
However, there is still one flaw with a voltage gauge. It is basically just an indicator as to whether or not your alternator is working (whether or not it is above 12 volts) because unless a battery is completely dead with absolutely no juice left (to even light an interior bulb) it will often be unreliable with its volt reading and read close to or even 12 volts. I had a situation once where all I got was the relay click (no turning over) and yet the battery still read good voltage on the multimeter.
The true test (what the autoclubs do when they come to give you a jumpstart) is a "load test" to tell you if your battery is still any good.
However, there is still one flaw with a voltage gauge. It is basically just an indicator as to whether or not your alternator is working (whether or not it is above 12 volts) because unless a battery is completely dead with absolutely no juice left (to even light an interior bulb) it will often be unreliable with its volt reading and read close to or even 12 volts. I had a situation once where all I got was the relay click (no turning over) and yet the battery still read good voltage on the multimeter.
The true test (what the autoclubs do when they come to give you a jumpstart) is a "load test" to tell you if your battery is still any good.
#5
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Car: 86 Trans Am, 88 Formula
Engine: 95LT4, 305TPI
Transmission: T56, T5
Guage won't help at all to let you know if the battery is going bad.
It will help show that your alternator is going bad though.
It will help show that your alternator is going bad though.
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I like ammeters. I've been considering adding one to my TA, even though I do have a full gauge cluster with volt meter. Sorry, looks like we don't really want to answer your question, huh?
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Car: 1995
Engine: 5.7
Transmission: T-56
he has a capacitor for his stereo. it stores juice for when the bass really hits. then recharges in a split second. and it has a volt meter on it.
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Car: 89 Camaro RS
Engine: 305 TBI
Transmission: 700r4
Axle/Gears: 2.73
the purpose is to store extra power, so when the bass hits hard there is a reserve of power that it can use with out causing a power spike on the cars power system. Probably only useful if you have a high power stereo system.
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Car: 85 firebird
Engine: Pos 2.8 pulled and replaced with a 350 tpi motor converted to carb.
Transmission: 700r4, vette servo,shift kit, hayden 15"x8" trans cooler.
actually they are useless. They are just an extra drain on your electrical system. If you have a high drain system you need thicker under hood wire (batt,alt,ground) and a high out put alt. All the cap is going to do is cause more of a drain. Look into the car audio section there is a post about them.
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They aren't useless by a long stretch, they just shouldn't be used as a charging system band-aid. If you use them right they give an instant high power charge to the amplifiers when they need it most: When the bass hits hard. If your charging system voltage drops below 13v when your car is running, you have other problems that need sorting that won't be cured with a cap. With a high output system, it can help a great deal with SQ, allowing tighter and more accurate bass response.
TomP- you can find small voltmeter gauges at most aftermarket parts places, but like zepher said, it's only going to indicate a bad battery if a cell is bad. To test properly, you'd need to do a load test on it. That would tell you your cranking and cold cranking amps. I haven't seen any portable version of the meter for that yet, but you never know
TomP- you can find small voltmeter gauges at most aftermarket parts places, but like zepher said, it's only going to indicate a bad battery if a cell is bad. To test properly, you'd need to do a load test on it. That would tell you your cranking and cold cranking amps. I haven't seen any portable version of the meter for that yet, but you never know
Last edited by onebinky; 12-26-2003 at 06:06 PM.
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