how much voltage should the battery be at when driving

S

smallboatlover

Banned
Joined
Dec 12, 2010
Messages
1,179
i'm not sure about the rpms but when i was out on the boat i have the fish finder telling my the voltage and the voltage got up to 15.6 volts that was as high as i saw it go. Is that bad or should it be then when cruising
 
C

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,142
Re: how much voltage should the battery be at when driving

Voltage that high would indicate you are running a non-regulated charging system, or have a malfunctioning voltage requlator. What year and model motor do you have? Voltage that high may not be bad. It depends on what kind of electronics you have, if any.
 
S

smallboatlover

Banned
Joined
Dec 12, 2010
Messages
1,179
Re: how much voltage should the battery be at when driving

i have a 50hp johnson 1985. i have a fish finder and a vhf and running lights
 
ajgraz

ajgraz

Lieutenant Commander
Joined
Mar 1, 2010
Messages
1,858
Re: how much voltage should the battery be at when driving

Your lights won't care, but look up the specs on your model of FF and VHF and see if they are rated for that kind of overvoltage. They probably are, most wil say "10-20VDC operating range" or somesuch.
 
Silvertip

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,762
Re: how much voltage should the battery be at when driving

Most electronics have over and under voltage protection designed into them. If voltage drops below a specific point the unit shuts down and if voltage goes higher than a specific threshold it shuts down. The overvoltage spec may be a minimum of 16 volts but may be higher. Check your manual.
 
JimS123

JimS123

Fleet Admiral
Joined
Jul 27, 2007
Messages
7,993
Re: how much voltage should the battery be at when driving

Your electronics will probably survive, but your battery may boil over. Check your battery case to be sure its not full of acid.

But before you get too concerned, check it with a good multimeter. Dash Voltmeters and depth finders are usually not too accurate.

You should have a true reading of about 13.5-14.
 
You must log in or register to reply here.
Top