Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: oldguy on July 16, 2023, 01:18:10 pm

Title: Not charging
Post by: oldguy on July 16, 2023, 01:18:10 pm
In my post, Trip to Saskatchewan, my alternator quit charging and thought it was sticking brushes
but further checking I found when the alternator was hot I had no exciter voltage. I have a Balmar
Voltage regulator and when the alternator gets too hot the regulator slows down or stops the alternator
from charging. I will raise the temperature a couple of degrees and will phone Balmar tomorrow.
The first morning out in the trip it probably was charging but I had other things on my mind. It was
sure nice having solar as I didn't worry about the no charging and it took 6 days before I figured out
what was wrong.
Title: Re: Not charging
Post by: Chuck & Jeannie on July 16, 2023, 03:11:37 pm
It was sure nice having solar as I didn't worry about the no charging and it took 6 days before I figured out what was wrong.
You can get along fine without a working alternator.  Just start the generator and activate the BOOST switch.  Both battery banks will be charged by the inverter/charger.  Some Forum members have driven across the country and back this way.

Title: Re: Not charging
Post by: Dakota Slim on July 16, 2023, 04:04:36 pm
Did you check your isolator?
Title: Re: Not charging
Post by: oldguy on July 16, 2023, 06:20:27 pm
I have a Blue Sea isolator and it closes to charge either way and for the start battery it
is hooked directly to the alternator. The Balmar regulator was doing what it is designed
to do but I am sure I can knock the temperature up a bit, I will check with Balmar
tomorrow.
Title: Re: Not charging
Post by: oldguy on September 03, 2023, 03:33:12 pm
So I have been trouble shooting and and when the alternator gets to 121F the charging rate
starts to drop which shouldn't happen until it gets to 230F and when I disconnect the temperature
sensor it jumps back up to where it is supposed to be. I'm going to get a new temperature sensor
and see if that fixes the problem which Balmer suggested.
Title: Re: Not charging
Post by: prfleming on September 03, 2023, 05:39:10 pm
I've got the same setup on our Roadtrek for the 2nd alternator - a Balmar regulator with a temp sensor. A suggestion would be to get an IR temp gun and compare the temp gun reading of your alternator to the Balmar temp readout.
Title: Re: Not charging
Post by: oldguy on September 03, 2023, 09:26:48 pm
I have done that Peter and they are way different so the problem is either the sensor or the
regulator and the sensor is usually the cause according to Balmar
Title: Re: Not charging
Post by: Protech Racing on September 03, 2023, 09:35:00 pm
You can add a resistor and change the temp signal.  Start at 1000 ohm
Title: Re: Not charging
Post by: oldguy on September 04, 2023, 03:14:11 pm
My cousin asked a friend who installs Balmer regulators if he has any problem with sensors and he
said he has often seen where people but the alternator sensor leads onto the  the battery sensor
connections on the regulator which is what I did, so I screwed up. It should now work fine.
Title: Re: Not charging
Post by: prfleming on September 04, 2023, 04:40:14 pm
Interesting. Roadtrek had my voltage sense lead connected directly to the alternator output B+. While this worked, I ran a new sense wire all the way back to the house battery + post where the inverter is connected. This then boosted the alternator voltage to account for the voltage drop of 150 amps over 20 feet of 4/0 cable when cooking with the microwave or hibatchi grill with the engine idling. The inverter is much happier with a full 14 volts to work with.