SternWake
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The benefits of an Ammeter are one can see what their charging sources are contributing the battery, and what the electrical loads are removing from the battery. A voltmeter alone tells very little in comparison.
This linked product is a voltmeter and an Ammeter:
https://www.amazon.com/bayite-Digit...8&qid=1479529371&sr=8-4&keywords=bayite+meter
I have one of these, currently( pun intended) measuring total alternator output. The display is on my dashboard.
Soon, I will move the sensor to measure amps into or out of house battery.
many people look at voltage and make wildly inaccurate guesses as to battery state of charge or how much charging is going on, but without knowing the amperage flowing at that voltage, are almost completely blind.
Say a voltmeter shows 14.7v when driving.
What does this represent? Only that the vehicles voltage regulator is allowing, at that moment, 14.7v and the alternator is making only enough juice to maintain that voltage.
Say the sensor is over the house battery cable and one is driving down the highway at 65mph. If all major house battery loads are turned off, and If it shows 2 amps flowing into a 100Ah house battery, one can then infer the battery is about 95% charged. If it shows 20 amps, the battery is about 75 to 80% charged. If it shows 50 amps the 100AH battery is likely well below 65% charged.
Note these numbers are not set in stone for a 100Ah battery, they are general numbers to show the trend of what the battery can accept at different states of charge..
The linked product requires only that one run one single wire/or cable, + or -, through the round loop. NO shunt required.
The 6 foot long 3 wire ribbon cable can be extended without loss of accuracy. I added 5 feet to the middle of mine.
How many amps are flowing into or out of the battery is very revealing and a great learning tool, and for 17$, and not requiring a shunt, this product can help members here understand their battery and charging systems instead of being nearly completely blind and surprised when the battery seems to not be performing as it once did.
Some interesting figures I could have figure out without this tool but never bothered doing:
My engine requires 8.2 amps to idle
My engine requires 12.2 amps at 2000 rpm
My blower motor on high can consume 19 amps.
My alternator at hot idle (550rpm) can generate 54 amps, cold idle (800 rpm), 74 amps When super hot it can only make 42 amps at idle.
My window motors each require 8 amps to start, but this tapers to 3.5 amps once the windows are moving.
When i move the hall effect sensor to the battery cable instead of alternator to battery cable it will show starter current, charging current, Key on current, stereo current, ect.
The ammeter is an enlightening tool. Without one, one is basically guessing.
I can also adjust my vehicles voltage regulator. the ammeter reveals that at 13.6v, my ~50% depleted battery requires only 18 amps, when I crank up voltage to 14.7v, it requires 46 amps.
This hall effect sensor is especially nice as it can go on the (+) cable where as most shunted ammeters require the shunt be installed on the (-), and with so many ground possible paths, much current can bypass the shunt if not wired properly.
17$ and Simple, and enlightening, and might save a member here money in batteries or inconvenience or give some confidence in how much house battery capacity they have to use that night.
The voltmeter on my unit is 0.2v low, but other report theirs are accurate.
It can be set to display voltage, amperage, or toggle between both, by a button on the back of the display.
Mine is set to only read amperage, as I have other voltmeters just below this display.
My only complaints with the product is I would much prefer the display to be red instead of green, and instead of placing a - in front of a negative reading, it will post a 12.2 amp load as 12.2. ( that extra period after the decimal represents the negative
instead of -12.2
If I wanted it to display voltage I would be annoyed it reads 0.2v low, but as said, other people who have purchased it have reported the voltage to be within 0.04 of a digital multimeter.
Note they have a 400 amp model too, but this will not be as accurate reading a 20 amp load.
It will not be damaged if you exceed the 100 amp rating
This linked product is a voltmeter and an Ammeter:
https://www.amazon.com/bayite-Digit...8&qid=1479529371&sr=8-4&keywords=bayite+meter
I have one of these, currently( pun intended) measuring total alternator output. The display is on my dashboard.
Soon, I will move the sensor to measure amps into or out of house battery.
many people look at voltage and make wildly inaccurate guesses as to battery state of charge or how much charging is going on, but without knowing the amperage flowing at that voltage, are almost completely blind.
Say a voltmeter shows 14.7v when driving.
What does this represent? Only that the vehicles voltage regulator is allowing, at that moment, 14.7v and the alternator is making only enough juice to maintain that voltage.
Say the sensor is over the house battery cable and one is driving down the highway at 65mph. If all major house battery loads are turned off, and If it shows 2 amps flowing into a 100Ah house battery, one can then infer the battery is about 95% charged. If it shows 20 amps, the battery is about 75 to 80% charged. If it shows 50 amps the 100AH battery is likely well below 65% charged.
Note these numbers are not set in stone for a 100Ah battery, they are general numbers to show the trend of what the battery can accept at different states of charge..
The linked product requires only that one run one single wire/or cable, + or -, through the round loop. NO shunt required.
The 6 foot long 3 wire ribbon cable can be extended without loss of accuracy. I added 5 feet to the middle of mine.
How many amps are flowing into or out of the battery is very revealing and a great learning tool, and for 17$, and not requiring a shunt, this product can help members here understand their battery and charging systems instead of being nearly completely blind and surprised when the battery seems to not be performing as it once did.
Some interesting figures I could have figure out without this tool but never bothered doing:
My engine requires 8.2 amps to idle
My engine requires 12.2 amps at 2000 rpm
My blower motor on high can consume 19 amps.
My alternator at hot idle (550rpm) can generate 54 amps, cold idle (800 rpm), 74 amps When super hot it can only make 42 amps at idle.
My window motors each require 8 amps to start, but this tapers to 3.5 amps once the windows are moving.
When i move the hall effect sensor to the battery cable instead of alternator to battery cable it will show starter current, charging current, Key on current, stereo current, ect.
The ammeter is an enlightening tool. Without one, one is basically guessing.
I can also adjust my vehicles voltage regulator. the ammeter reveals that at 13.6v, my ~50% depleted battery requires only 18 amps, when I crank up voltage to 14.7v, it requires 46 amps.
This hall effect sensor is especially nice as it can go on the (+) cable where as most shunted ammeters require the shunt be installed on the (-), and with so many ground possible paths, much current can bypass the shunt if not wired properly.
17$ and Simple, and enlightening, and might save a member here money in batteries or inconvenience or give some confidence in how much house battery capacity they have to use that night.
The voltmeter on my unit is 0.2v low, but other report theirs are accurate.
It can be set to display voltage, amperage, or toggle between both, by a button on the back of the display.
Mine is set to only read amperage, as I have other voltmeters just below this display.
My only complaints with the product is I would much prefer the display to be red instead of green, and instead of placing a - in front of a negative reading, it will post a 12.2 amp load as 12.2. ( that extra period after the decimal represents the negative
instead of -12.2
If I wanted it to display voltage I would be annoyed it reads 0.2v low, but as said, other people who have purchased it have reported the voltage to be within 0.04 of a digital multimeter.
Note they have a 400 amp model too, but this will not be as accurate reading a 20 amp load.
It will not be damaged if you exceed the 100 amp rating
