gauge difference? volt/batt/amp

[stackz]

wanting to add some sort of gauge so I'll know the condition of my charging system on my little mercury outboard.

cant figure out which one I want??

I'm assuming the volt would be best as the batt gauge would just tell me about the battery itself and I'm sure the amp gauge does something similar to the volt gauge but just shows charging amps versus system voltage during running conditions.

anyway, which would you guys pick and anyone have any wiring diagrams since most of the gauges on ebay dont come with any instructions...

 

[Silvertip]

Re: gauge difference? volt/batt/amp

Voltmeter: Measures system voltage with engine running. Measures battery voltage when engine is stopped, key in RUN. Any reading above 13 volts indicates charging system is working with engine running. Anything less than 12.6 with engine running indicates system is not working. If the voltmeter starts out below 12.6 but gradually rises with engine running indicates tht the battery is deeply discharged but is being gradually charged. Easiest to install and provides more useful information and easiest to understand for most folks.

Ammeter: Installs in series with the main electrical system. Measures current flow into (charge rate) and out of (discharge rate). A minus reading indicates the charging system is not working or is not capable of keeping up the the power demands of the accessories (the electrical load). A positive reading is the charge rate (the amount of current in excess of the load) that is going to the battery. Not a practical gauge for low amperage outboard electrical systems. The gauge would rarely move off zero. More difficult to install and more difficult to understand for most folks.

Battery Gauge: Nothing more than a voltmeter with a face that reads percent of charge based on battery voltage. A useless adaptation of a voltmeter. Installs in the same manner as a voltmeter. Battery "conditiion" can only be checked with a hydrometer or by a load test.

 

[stackz]

Re: gauge difference? volt/batt/amp

ok cool. so I wasnt that far off base with my assumptions.

volt meter it is.

thanks again

 

[CharlieZulu]

Re: gauge difference? volt/batt/amp

Agree, but where can one get a voltmeter that has an LCD digital readout -- those needle gauges are useless if you're trying to split hairs and read tenths of a volt, i.e 12.6 13.0 etc

 

[Silvertip]

Re: gauge difference? volt/batt/amp

You don't have to split hairs. An analog voltmeter is usually calibrated 10 - 16 volts in one volt increments. If the needle is half way between marks that's 1/2 volt. Do a search on Marine Digital Voltmeters if that's your need. if you need to worry about anything more than 1/2 volt -- well -- break out an accurate VOM.