Allanson D20-BRA-A

[Jonathan L]

Hi Everyone,

I recently purchased a 1987 Bigfoot 17' trailer and it has an Allanson converter in it. I purchased a new battery and checked the charging voltage going to it when the trailer is plugged in to 120v. The voltage was only 9.8 volts. Thinking there might be a voltage drop along the line, I checked the voltage directly inside the converter housing. It still read 9.8v.

My question is, shouldn't this be more then 12v? I will probably replace the charging unit with a modern multi stage charger but I would like to know why only 9.8v?

Thanks!