Arduno Uno and most (if not all) derivatives has an Analog to Digital Converter (ADC) which is basically the thing that connects the digital world to the real world. This project walks us through the processes of making a quad channel voltmeter using an Arduino, some resistors and a 2x16 liquid crystal display (LCD).
The resistors are configured into a voltage divider to attenuate incomming voltages to the levels that the arduino can measure - the Arduino program will then cycle through the four voltage dividers measuring the DC level on each output and displaying it on the 2x16 LCD screen.
The resistors are configured into a voltage divider to attenuate incomming voltages to the levels that the arduino can measure - the Arduino program will then cycle through the four voltage dividers measuring the DC level on each output and displaying it on the 2x16 LCD screen.
hello good day sir very nice project, i am trying to monitor voltage of battery of a car, is this applicable sir? thank sir God bless
ReplyDeleteHi Angelo,
ReplyDeleteYes this sure can be used to measure the voltage of a car's battery - but please take note that the car battery is around 12V and this controller in running at 5V you will need a voltage divider that would step down the 12V maximum into the 1.2V maximum (im assuming that reference is 1.2V) so thats around 1/10, a voltage divider of 900kOhms and a 100kOhm resistor would do. Also you might want to add a low pass filter just the simple resistor capacitor filter will do to clean up any noise that you might pick up from the environment :)
cheers,
bootfetch
Hey Angelo, its possible to measure this way, but you have to be carefull.
ReplyDeleteCar systems run at nominal 12V, but under some conditions voltage can go up to 40V and even into negative.
For Example a car battery has 13.8 V to 14.4V when fully charged.
So you have to add limiting devices like a Z-Diode.
Check this out ( its for solar-systems - but they also work with lead-batterys )
http://translate.google.fr/translate?hl=fr&sl=de&tl=en&u=http%3A%2F%2Fwww.strippenstrolch.de%2F1-4-10-akku.mit-c-control-messen.html
Yes this is true, the variance in voltage may also vary from one type of car battery to te other - some wet cells behave differently from dry cells and NiCad and Lithium Ion.
ReplyDeleteBetter to check first the type of battery.
@thomas: wouldn't a Z-diode's leakage current enough to drain the battery over time? im not not really sure though.