Morningstar TS-MPPT-45 Absorption voltage setting to high

Fryedaze

I have a new TS MPPT 45 that is setup for lead acid batteries. I have set the dip switches to the #5 battery setting which should have an absorption voltage of 14.6 Vdc. The remote Morningstar panel and a Victron battery monitor both indicate that the batteries are at 15.1 in absorption stage. I ran the independent voltage sensing leads to the controller. I have double checked the dip switch settings. If the controller sees 15.1 why isn't it cutting back to 14.6Vdc.

unseenone

Have you installed a temperature and voltage sense wire?
What is the temperature where the batteries / unit is setup up?
Do you have the optional meter set up on it?
Are these new batteries, what are they, brand, configuration, capacity, etc.

The switches to set are 4, 5, 6 and the manual states on page 19, that the Equalize volts are 15.1 15.3 or 15.4 depending on the option you set. Perhaps you just need to allow the batteries to complete a cycle.

Turning switch 7 to off, will disable the equalize mode, so you can at least eliminate this concern temporarily.

Switch 2 and 3 should be set appropriately to the 12 volt setting if that is what you are using.

Manual Excerpt

All charging settings are based on 25°C (77°F). If the battery temperature varies by 5°C, the
charging setting will change by 0.15 Volts for a 12 Volt battery. This is a substantial change in
the charging of the battery, and the use of the Remote Temperature Sensor (RTS) is recom-
mended to adjust charging to the actual battery temperature.
The need for temperature compensation depends on the temperature variations, battery type,
how the system is used, and other factors. If the battery appears to be gassing too much or not
charging enough, the RTS can be added at any time after the system has been installed. See
Section 2.3 - Step 4 for installation instructions.

I hope this helps, as at least a start to double checking the settings, and more information needed to advise you.

waynefromnscanada

First thought - - battery temperature voltage correction. Is remote battery temp sensor properly installed, and what is battery temperature?

Fryedaze

Thanks folks, the tech rep at Morningstar called me today. The 15.1 volts is correct. The temperature compensation drives the charge voltage up at lower temps. The Batteries are sitting in a boat at 45F. Looks like you guys had it solved. I have both the remote voltage and battery temp sensor. All is cool.