Is This normal?

[Tikvah]

This is my first time with a real inverter/charger and so I'm seeing new things.  So this morning I look at my voltage from the 12volt side of the Vanner and I'm reading 14.4

Is this normal?  Before I used a car type battery charger and was always between 12 and 13.

[bobofthenorth]

In short "maybe".  A three stage charger should briefly run the voltage to these levels during the absorption stage. If you see 14 volts for extended periods then something is wrong.

[eagle19952]

In short "maybe".  A three stage charger should briefly run the voltage to these levels during the absorption stage. If you see 14 volts for extended periods then something is wrong.

check/verify it with an accurate VOM

[Lee Bradley]

Check your manual, 14.4 is right for bulk but should be for a limited time my trace runs bulk for 2 hours and goes to float 13.3 volts.

[Tikvah]

Yup, shortly after posting this question it went down to 13.3

[Jon]

Inverters can be programmed or for specific battery types and if you have the opportunity it should be done. Each battery manufacturer will provide voltages for bulk, absorb, and float. The voltages posted sound like they are for lead acid or AGM.

What some inverters will not do is go to float if the battery voltage level is OK. Some inverters are set so every time power is removed and reapplied they go to bulk, and then they hold at that charging voltage for a specific length of time instead of measuring battery condition and applying the appropriate charge voltage. That is better than a poke in the eye with a sharp stick, but not much better because if the power is applied and shut off and reapplied often enough the batteries will be cooked.

[Lin]

Yup! I lost a whole bank of AGM's once to a charger that did that pre-programmed bulk timing thing.

[Seangie]

Dave -

Most 3 stage charges hit with high amperage first and you'll see the voltage slowly build (if your batts are low) from 12.8 up to 14.4 (I believe 14.4 is bulk for lead acid) Once the bulk charging is done (30 - 60 min) it goes to voltage charging which will be about 13.4 volts (For lead acid, AGM is a little higher ) and then float is around 13.2.  Your manual should have a chart or something explaining this.

-Sean

[TomC]

Any good inverter/charger should be of the "smart" type. Since I run AGM batteries, I have the maximum charge at 14.1 volts. Then float at 13.2 volts. With that setting, my last set of 8D Lifeline AGM's lasted 7 years. Good Luck, TomC

[Lee Bradley]

Yup! I lost a whole bank of AGM's once to a charger that did that pre-programmed bulk timing thing.

Was that bulk charging or a pre-programmed equalization?

[Jon]

It is hard to generalize with inverters now because they are and have been modernized to do some pretty amazing things from starting the generator to producing a pure sine wave, to syncing frequencies with shore, generator or other inverter power. Now they can be linked if desired.

It is true some model inverters ALWAYS went to bulk charge voltages, but now some are only going to use change voltages as required. It is pretty important to read the manual for your inverters because they all have different features.

[Lin]

Lee,

This was on my last bus. It's been a while so I do not remember the make of the charger (I had a separate inverter).  What the analysis of what caused the problem was that we were plugged into power continually for a long time.  Much of the lighting and some other stuff were 12v. so when those things were turned on, the charger, which was three stage but apparently not very smart, would sense the draw and go into a bulk charge mode and continue that mode for a factory preset period of time even though the light, fan, etc. may have already been turned off.

The inverter/charger I have now does not do that.