Would like to wire in an ammeter
#22
02-25-2014, 10:18 AM
Member
Actually kyle, you're incorrect (if i understand what you're saying here). You seem to be saying current will drive the voltage in a circuit; that's actually a common misconception (don't worry, you're not the only one). It's the other way round; voltage is the driver.
You can't "make" current; the only way to make current is to apply a voltage to a circuit. You can have voltage w/o current in a circuit, but you cannot have current w/o an applied voltage.
You can't "make" current; the only way to make current is to apply a voltage to a circuit. You can have voltage w/o current in a circuit, but you cannot have current w/o an applied voltage.
Getting to the point- by using Ohm's law, you can deduce that if the current does not supply the load then voltage will suffer.
i found this picture by doing a google image search of ohms law, it might help explain better-
http://www.hondaforeman.com/attachme...w-triangle.jpg
#23
02-25-2014, 08:50 PM
- What is your resting (key-off) battery voltage?
- What is it while the starter is cranking (but before the engine starts)?
- What is it with engine idling with lights and other accessories on?
- What is it at above idle (2k rpm)?
What is "good" voltage? Do you have an onboard voltmeter?
So I thought it would be good to know what kind of current is going back into the battery. In searching posts on this forum, several members have claimed you can have good voltage but poor current. That is the condition I wanted to test for. I liked "firebirdparts" replies, so I have a good idea on how to proceed now. Thanks for all the responses.
#24
02-25-2014, 08:55 PM
What I am talking about is known as "ohms law" and is an algebraic equation. the idea is to find voltage you multiply amperage (current) and resistance (load). you can also find current by dividing voltage by resistance, or resistance by dividing voltage by current.
Getting to the point- by using Ohm's law, you can deduce that if the current does not supply the load then voltage will suffer.
i found this picture by doing a google image search of ohms law, it might help explain better-
http://www.hondaforeman.com/attachme...w-triangle.jpg
Getting to the point- by using Ohm's law, you can deduce that if the current does not supply the load then voltage will suffer.
i found this picture by doing a google image search of ohms law, it might help explain better-
http://www.hondaforeman.com/attachme...w-triangle.jpg
Are you trying to teach me ohm's law?
#25
02-26-2014, 11:35 AM
Member
#26
02-26-2014, 11:42 AM
Member
In the old days it was quite common to see trio guages. Volts, amps and oil pressure. Something is not quite right with my charging system. After start, the voltage drops and then rises. After that I have good voltage, but i don't seem to get a fully charged battery unless I go for a longer ride.
if that's the problem you need to do a charging system test with a vat40/vat45. This will load test both the battery and alternator so you can pinpoint the problem
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