Tri-Metric programming help

Pick a reasonable value like 50AH. Discharge the battery to about 50%, measure the battery SOC and compare to the meter SOC. Adjust the value for the meter as required.

Just a swag!!

Trojans site shows the decrease in AH capacity between 5 hours discharge and 20 hours as about 20%. At the 65 minute rate this battery is 27 AH; giving the benefit of the doubt, take 27 by 140% (120% increase from one hour to 5, times 120% increase from 5 to 20 hours) use 38 AH.

I tried finding some table that went from the 1 hour rate to the 20 rate, and just can't find any, so you'll have to swag it.

As others have said, this is not the right battery. That said, sometimes you just gotta use what you got, not what you wish you had. This ought to work well enough to get you in the ball park.

Good Luck,
Doug

I would use less than 10% of the 440CCA, or less than 44AH, and that is surely too high!

My Optima AGM is a dual purpose hybrid with 750CCA and only 55AH where 10% would be 75AH.

I have a Deka AGM dual purpose with 525CCA and 79AH, or more than 10%.

It is a starting battery. Try 55/750 x 440 = 32AH.

Better yet, get a proper battery!

HTH;
John

Given that the RC is an hour at 25 amps, I wonder if the capacity is actually under 50 amp hours.

Jim

The Crown website calls this a marine starting battery, a small gp24. It lists reserve capacity of 65 minutes at 25 amps. As far as I know, there is no tried and true method for converting RC to amp hours. Unless you are plugged in every night or have a generator to run quite often, you won't get far. Without knowing battery capacity you can't really set P3 or P2. P1 should probably be 14.2 or 14.3 if your converter has an absorption mode of 14.4. A guess for P3 would be 50 to 70 and 1 for P2. This will get the meter operating, but the numbers won't mean much.

Look into the twin 6-volt setup sooner rather than later.

Your TT came with one Group 24 starting battery??? Personally I'd have strong words with my RV dealer and/or Outback for installing the wrong battery... but I digress.

The spec's on the MAR-500 are 550 MCA & 440 CCA, but Crown doesn't list a capacity in Amp-Hours, because that battery was never intended to be cycled or used as a house battery. I would venture a (generous) guess that it's in the neighborhood of 50-55Ah.

As a starting point, I suggest that you use a P3 value of "50"
The P1 and P2 values are going to depend on your charger (converter?) and its charge profile, so more info about this component would be helpful (can you verify the charge voltage with a VOM? If not the brand & model will suffice). Most OEM converters peter-out around 13.6 Volts so I'd use "13.5" as your P1 value. Start with "1" as the P2 value.

These values will get your Trimetric working... No guarantees on "correctly".

Hope this helps.
Cheers
-Mark

I would not know what to guess for Ah on a starting battery, but if you use it like it only has a few and recharge immediately, it will live much longer. SWAG at 70 but safer to put a lot fewer? The hybrid marine group 24's often have 85+/- and they are closely related to starting batteries.

Jim

Nope, that is what is stated on the battery itself. I know 440 is way wrong. I really want to put t105's on it but space is going to be an issue. Also cost at this point has me staying with what I have.

Looks like that is a pure starting battery, group 24. Is that a typo on the number of minutes at the 20 hour rate?

Jim