APU Tri-pac not charging batteries

Do you have a Cobra inverter? It gives a watt and volt read out. What's the volts say if you have one? My Tripac supplies 13.5 V which is bare minimum acceptable.

 

A 65 amp alternator is only 780 watts, so you are killing the batteries if you are running lights. That should show on your amp/volt meter as below 12.6 volts. you need to limit your power use to below that to have the batteries hold their charge.
Also continuously discharging the batteries to about 11 volts they will not live long.

 

Yes I really think the TriPac ought to have a bigger alternator, if you are using a medium size, less than 1000 watts microwave, you are pulling down the batteries even with the unit running. Not to mention whatever other loads are on the entire system. I always run my main engine for the few minutes the microwave is on.

 

I use Cat batteries, a combination deep cycle-starting battery. I was buying good starting batteries and getting 12-14 months out of them. I just replaced my Cat batteries after 3 years. They cost around $100 each. If you're interested I'll get the model number for you.

 

The use of deep cycle and standard batteries does not work, Freightlinner tried it, the batteries charge at different rates and after a very short time the standard batteries are overcharged and the deep cycles do not fully charge.
Caterpillar does not make Batteries.
Freightlinner does not make Batteries, what they do, is sell enough batteries that the stock is fresh. Over the years It was shown to me that the 760 CCA batteries lasted a lot longer than the 1000's did. Buy batteries in full sets, clean connections, coated with die electric grease. And wash the tops off, regularly. A dirty battery will discharge, all by itself, try it some time with a volt meter, one terminal on either post and the other rub it around the top on the case, try it after it is washed and dry.

 

The batteries are deepcycle-starting in one battery, not two different batteries. I know several people that are using these batteries after having problems with Optimas.

I realize Cat does not make batteries. Most batteries are made by three manufacturers and different labels put on them. I believe the Cat batteries are made by EastPenn.

I agree the 760s last longer than 1000s.

 

Thermoking makes a 120 amp for the tripac... the part number is 45-2258. Make sure you use the cooling fins off of the old one as the new ones are reversed. If you use the fins that comes on the new one you WILL burn it up from lack of cooling.

 

Any chance you have a pic of these cooling fins? In the 7 alternators I have been thru in 8600 hours, I have NEVER had one that had any kind of fins on it!

But I am happy to report that the most recent alternator I had put on at around 7000 hours, along with a change in settings is still working fine. Increasing the the kick on voltage, so that the unit does not have to work as hard to recharge the batterries really seems to have made a difference.

 

Did you installed the upgraded alternator yourself? I was also told that the new alternator requires a wiring harness...not sure if this is true. I'm thinking of doing the installation myself...if its just an on/off deal. Does the electrical charging system need to be readjusted after the installation?

 

May I ask a stupid question?

Can the 4 batteries be isolated into two banks...one for starting other for misc use and let the misc usage be recharge by the APU (would also installed a high amp alternator)? This is typically done in the marine and rv world. If they can be isolated, then would it be prudent to install deep cycle on the misc use bank...since does batteries would experience excessive recharging?