Checking volts at battery

[Boatist]

Re: Checking volts at battery

Best way to test the regular is to just put that digital voltmeter on your battery. When tightening connections be careful. Probably best to disconnect the battery first. Voltmeter are very cheap these days. Make sure your battery connection is clean and thght as a loose connection will give false reading and blow the output diodes or voltage regulator.

 

[QuadManiac]

Re: Checking volts at battery

Digital V/O/A meter at Harbor Freight on sale right now for $2.89, WITH battery, lol... how can anyone not have 3 at that price? And they work well. Just not auto-off, so if you forget to turn off the power, you lose the battery.

 

[Keith7481]

Re: Checking volts at battery

With the motor running, if the hand held voltmeter and my dash gauge register different readings, does that mean the gauge is bad, or the voltage regulator??

 

[QuadManiac]

Re: Checking volts at battery

That means that either the guage or the hand held meter is reading incorrectly... but I'd be more inclined to trust the hand held.

 

[jtexas]

Re: Checking volts at battery

Analogue gauges are generally not precise enough to measure a battery state of charge - but they're useful enough for informing you of changes or fluctuations in voltage. Dropped voltage due to long runs of wiring and connections gives some measurement error - and wiring starts to go bad, get a little corrosion, wires chafe, etc, you don't know about it till it breaks. Whereas, in my experience, a digital handheld, even the cheap ones, generally speaking will either be right, or else not working at all. I shoulda thought of that before sending you out for parts.............

 

[QuadManiac]

Re: Checking volts at battery

BTW, what ever happened to ammeters? I don't know about boats of the time, but unitl the early 70's or so, vehicles with gauges (not idiot lights) had ammeters instead of volt meters. Much better at diagnosing the charging system! I know, the long, large leads were a pain, shunt systems were more expensive, but got rid of the large leads to meter...

I'd kinda like to have both. Nothing like voltage AND current to tell you what's going on. Anybody make a marine ammeter these days?

my two cents

 

[bruceb58]

Re: Checking volts at battery

BTW, what ever happened to ammeters? I don't know about boats of the time, but until the early 70's or so, vehicles with gauges (not idiot lights) had ammeters instead of volt meters. Much better at diagnosing the charging system! I know, the long, large leads were a pain, shunt systems were more expensive, but got rid of the large leads to meter...

I'd kinda like to have both. Nothing like voltage AND current to tell you what's going on. Anybody make a marine ammeter these days?

my two cents

Main problem is the huge voltage drop running from the alternator all the way to the gauge and back. You also really should fuse this wire which wasn't commonly done back then. There are other issues too such as reliability of the connections, the gauge itself...

A shunt system would be better but really not needed. A measure of voltage pretty much tells you if the alternator is dead or working somewhat.

 

[QuadManiac]

Re: Checking volts at battery

Agreed. But, 'back in the day' it sure was nice to be able to see that damn 2 Amps due to the trunk light being stuck on, instead of coming out to a dead battery the next day. Voltmeter won't tell you that, lol.

 

[Keith7481]

Re: Checking volts at battery

Not a problem, I didn't buy any parts yet I"m off to buy a meter so I can get a look at the voltage when the motor is running. With a bit of luck, I'll just need a new regulator, but will check to make sure I have good connections first. Thanks everyone.

Keith