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Alternator charges the battery at a regulated 5 A/h. It charges at a much lower rate than specified on the batteries usually 1/10 of their capacity. This is because charging at full pin would overheat the battery, generate high levels of hydrogen gas and dramatically reduce the longevity of the battery. 61 A/h battery at 5A/h charge rate would fully charge ...


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There are three different tests you can do to check your charging system and battery (there are others, but I'll just talk about the big three): Voltage with engine off Using a multimeter, select volts-dc on the selector switch, then put the red lead to the positive and black to the negative. For a fully charged battery the reading should be in the ...


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Your question is relatively vague, however there are a few things that could be at issue. You could have a short circuit in your system that is draining the battery, which could also overload the alternator, causing it to fail. Since most of the circuits in a car are behind fuses, a short causing the problem you describe would have to be before the power ...


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Is the field coil connection connected? If not the alternator will not produce any output at all. The field coil supplies the magnetic field needed to induce current in the alternator coil winding. There are 2 connections on a alternator. B+ Output of regulator Field Field coil connection The ground is the casing of the alternator. The plug ...


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Sounds a bit like alternator whine. A noise suppression filter capacitor may be bad. A unfiltered alternator would send pulsating DC ripple into the radio creating a whine that varies in frequency. It is usually located on the back of the alternator(or at least it used to be). Alternators generate AC (Alternating Current) which is then converted into ...


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There is NO free lunch, you will need many batteries and a much better alternator. You could in fact attach a window mounted air conditioner like @Spehro Pefhany suggests. OR TEC Thermo Electric Cooling There are peltier elements that also generate a cooling effect compressor free. They are essentially a plate of ceramic postively charged, and one ...


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Yes, this is possible. Several companies (VAG, BMW) have switched to AC units that are driven by electric motors. For BMW, this is part of their Efficient Dynamics strategy, where they'll switch the compressor on/off depending on engine load to optimize fuel consumption. When the weather's not too hot, you can run the compressor intermittently without the ...


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The one tool you will need to purchase / borrow is a Volt Ohm Meter (sometimes called a Multimeter). Then you need to use it to read voltage AT THE BATTERY, before the car is started and after the car is started. My guess is you won't see any voltage difference. Before the car is started, I would guess you'd see voltages like 12.6v or so. After the car ...


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In order for an an alternator to function it requires a functional battery. The battery current is required to required to energize the field coil which produces the magnetic field required for the alternator to produce energy. The alternator sends 5 amp-hours at about 3000 RPM to the battery and the balance of its output goes all the other systems in the ...


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Well, Teslas (and presumably other all-electric cars) have A/C so it's not impossible, but A/C takes a fair amount of power. On the other hand, Teslas store a lot of energy. The A/C is something like 2.4kW which is about 8,000 BTU/h or about 3HP. So using an electric motor on a conventional car might give you a few more HP briefly, but the alternator has ...


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The short answer to your question is no. As @JPhi1618 noted, the compressor is mechanically driven. Without the compressor you don't have any cooling. The AC runs by changing the state and pressure of a liquid, and compressing the liquid is a big part of that cycle. If you bolted an electric compressor onto the car you would have to find a way to switch ...


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I can't give you numbers or calculations without some work, but I can tell you than energy is never free. Cars have an A/C compressor that is mechanically driven by the engine because this is the easiest way to get the job done in a typical consumer car. An A/C compressor actually takes a huge amount of energy to operate. In fact a central A/C unit for a ...


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You'd backprobe the S and L terminals with the connector plugged in. So attach one end to a ground point and the other to the S or L terminal. Basically the S terminal is the Field terminal. The S wire gets power from the eng inj fuse and should have 14+V while the engine is running. The alternator grounds the L terminal when voltage is below threshold and ...


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The voltage being a little low (13.75 is not low enough to be considered a problem in any case) is not going to affect their RPM reading - as it's the frequency of voltage variations that is measured to get your RPMs. I'd be tempted to say your tach is out slightly. You could ask them about that. There is a smartphone app that you can use to gauge RPMs - ...


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Absolutely yes. I sell alternators all day every day - and a poor battery is often the root cause of alternator failure. A battery with a short in it will cause the alternator to run at full output for extended periods of time, if not continuously - and they are not built to do this. Alternators the world over are built to supply an initial high current, ...



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