Batteries charging at 18V?

[perryg114]

It is more like 14-15V on the highest charge level not 18V and even 14-15V is enough to do damage over a long period of time.

Perry

Originally Posted by thiel

I always thought that multistage chargers started high like 18 and then stepped down to a 12v float charge as the batteries got full. (I thought that was actually the very definition of a multistage charger.)

[TravlinMan]

It confuses me that ya said the trailer is unplugged and in shade.... How could the batteries hold that much voltage with no power source? That makes no sense to me. I agree with Bob the only thing that could feed it 18v is a failed solar controller that's givin it the full voltage of the panels. But that would only happen in sun....

[uncle_bob]

Originally Posted by thiel

I always thought that multistage chargers started high like 18 and then stepped down to a 12v float charge as the batteries got full. (I thought that was actually the very definition of a multistage charger.)

Hi

Battery charger descriptions have changed over the years. What we now call a staged controller: (... and once described differently)

1) Sarts out in a current limited mode. It shoves X amps in and watches the voltage.

2) Levels out as some defined voltage and sits there for a while

3) Cuts back to a lower voltage and "floats" there for a long time

4) Maybe (if it's a 4 stage) pops up to a higher voltage for a brief time to stir things up.

Normal voltages are all in the 13 to 15 V range for typical lead acid batteries at 70F. They shift by > 1/2V up or down at typical 3 season camping temperatures.

In the opinion of a lot of people 18 to 20 V on a battery is simply insane. When you talk to the guys who make those chargers, their answer is that it's intended for use on batteries that already are severely compromised. The main point is that you don't want to grab just any charger and slap it on your RV batteries. You need to get one that is designed for your application.

Why not name names? Most outfits make a bunch of chargers. They also change what they do over the years. What they made two years ago may not be what they are selling today. Model A may not work like model B. Being *sure* that this one is a problem is just as hard as being sure that another one is ok.

Bob

[TinCan Betty]

The batteries are only being charged at 18V when the trailer is connected to shore power. When not connected to shore power they read below 13.7V.

The local dealer told me they had a service blackout for trailers not purchased from them due to high summer volume but they could probably get me in in the fall. Contacted Jackson Center and they contacted the local dealer and I now have an appointment for Thursday at the local dealer. Jackson Center is shipping the charger to them to make sure the part is available for replacement.

Very pleased with the response from Airstream at Jackson Center, they were professional and very quick to respond by email.

[TravlinMan]

You are the 3rd or 4th person who has mentioned months long waits for dealer service in the last 2 weeks. To me, that's crazy. Glad to hear JC agrees.

[TinCan Betty]

Originally Posted by TinCan Betty

The batteries are only being charged at 18V when the trailer is connected to shore power. When not connected to shore power they read below 13.7V.

The local dealer told me they had a service blackout for trailers not purchased from them due to high summer volume but they could probably get me in in the fall. Contacted Jackson Center and they contacted the local dealer and I now have an appointment for Thursday at the local dealer. Jackson Center is shipping the charger to them to make sure the part is available for replacement.

Very pleased with the response from Airstream at Jackson Center, they were professional and very quick to respond by email.

Took the trailer to the local dealer last Thursday and they replaced the converter/charger in 90 minutes under the 2 year warranty. The batteries were not impacted by the couple of minutes of charging at 18V. The trailer is reading normal charging values now.

[TinCan Betty]

The converter went out again, fortunately we were setting up at Jackson Center for other warranty items when it went bad with the same symptom as before, high charging voltage greater than 17 volts.

The technician quickly found the problem, a electronic component with an attached heat sink broke off from the circuit board in the converter that was bouncing around inside the converter. The electric component was probably a transistor as it was mounted on three very fine wires. We had driven over some very rough roads in TX, OK, and AR on the trip. Attached are photographs of the failed component and the component mounted in the new replacement unit.

I am going to purchase a Progressive Dynamics replacement unit tomorrow and carry it with us as a spare as I think the problem is likely to occur again.

Thanks!

Bob