High voltage at batteries

[Jason Worman]

Hi All,

So as I am checking things today, I open up battery compartment and use multimeter to check voltage on all batteries and was surprised that batteries are showing over 17 volts per battering including the starting battery. Switched off my Freedom 458 inverter/charger. Any thoughts as to why the voltage is running so high? Have an Echo charger hooked up as well. Batteries are not hot at all. They are 13 voltage deep cycle marine batteries.

Thank you,

Jason

[Steve Huber Co-Admin]

Jason,
The solar panels can output that much voltage but since current is low, no problem.
Steve

[Jason Worman]

Steve,

Thank you for your reply, I don't have any solar on my rig, just the Xantrex Inverter/ Charger. The voltage at batteries remained high until I turned the charger off. Rechecked each battery once Charger was turned off and voltage began to drop. Checked Link remote to make sure all settings were correct such as hours and battery type. In times past batteries always read 13.5  or 13.6 volts while Charger on and in float mode. Weird

Jason

[Steve Huber Co-Admin]

Jason,
Sounds like the charger isn't sensing actual battery voltage. Suggest you turn off charger until you track down possible broken/disconnected wire. Also possible that charger has gone west or that battery voltage settings are incorrect.
Steve

[Eric Maclean]

Jason
I agree with Steve it sounds like the inverter charger is not getting an accurate voltage sense reading causing the over charge or the voltage regulator in the inverter has gone bad.
1) check voltage at the battery while you have a load on the inverter ( inverting not charging) microwave works well for this
Record the volt  reading.
2 ) check the voltage at the inverter battery cables at the inverter with the same load on the inverter and record your voltage.
If the voltage at the inverter are much lower 3 to 4 volts you have a connection or cable problem causing your volt drop.
3) if the unit has a separate voltage sense wire that's the place to go check all the connections for possible resistance which would give the inverter a fault low battery sense voltage.
Read the voltages at both the battery and the inverter ends of the sense wire with and without the charger running to determine if you are getting a volt drop on that wire.


The voltage regulator would be my bet and as it is internal it may or may not be adjustable and would likely require a good electronics service tech .
It may be time for a shiny new sine wave inverter.

Eric

[Jason Worman]

Eric,
Should I unhook from shore power to do what you recommend?

Jason

[Jason Worman]

Eric,

One more thing, the charger has been off for 13 hours and all the batteries including the starting battery are still at 16.21 Volts. Batteries are still in float charge. Have to head to work will check things tonight.

Jason

[Fred Brooks]

   Jason, Try another meter, not likely 2 different kind of batteries could have 16 volts in them after 13 hours. Fred

[Chuck Jackson]

Jason,

 I’m kind of leaning towards where Fred is going with this. If you don’t have immediate access to another meter try checking another vehicle maybe your daily driver to see what the voltage is. If it’s around 16, then I’d spring for another meter.

[Bill Lampkin]

With the inverter off, unplug the battery temp sensor at the inverter, if your inverter has one. Then turn on the inverter and recheck. I had a bad temp sensor and it caused the inverter to do weird things.

[Jason Worman]

Hi All

Thank you all for the advice, will try another meter. Bill I tried the temp sensor trick and no changes. Will keep you all updated.

Jason

[Jason Worman]

Fred,

You get the A today, I tried the multimeter on my daily driver at lunch, it also showed 16.20 volts, out with the old and in with a new one. Just renewed my membership yesterday and now I know why. !!

Thank you everybody

Warmly,
Jason Worman