TriMetric Battery System
- TM-2025-RV
- TM-2025-A
- TM-2020
- TM-48VA
The TriMetric is used to monitor battery systems used in remote homes, RV’s or boats that have batteries that store solar, wind, or possibly generator powered chargers. They will help you maintain your batteries. The cost is under $200, including a “shunt”, which is required, and which in some systems is already installed.
All models are designed to monitor the following:
- “Percent Full” (“State of charge”) of your batteries, so you can see if you need to charge them more, or check that overall usage is less than your charging resources.
- Volts of the batteries, for example to check that they are being charged at proper voltage.
- Energy going in, or out of your batteries, measured in Amps or Watts, so you can see that your charging sources are charging properly, or how much current your loads are using..
- How many days since the batteries were fully charged: to remind you to not wait too long between fully charging your batteries to maximize their life.
The newer TM-2025’s have much in common, and also a few advantages over the older TM-2020, which we believe makes the TM-2025 a better choice now. There are also two choices of TM-2025, the TM-2025-RV and TM-2025-A, but there is no operational difference—they only differ in their size and the color of the front label. The TM2025 A is designed to fit an a “double gang” electrical box of appropriate size, and does not come with its own box. The TM-2025-RV is physically slightly narrower, and has its own box, with more muted color scheme designed to fit with the interior of an Recreational Vehicle.
TM-2025 improvements over TM-2020:
- The TM20205 is easier for you to program the necessary system parameters.
- The TM2025 has some minimal data logging, which can be useful for a technician to diagnose some common setup or operational problems with battery systems.
- The TM-2025 will operate with (nominal) battery systems from 12 to 48V. The TM-2020 will operate with 12 or 24 V systems, but requires the addition of the “TM-48VA” Adapter and lightning protection board when using it with 48V battery systems. This also provides lightning protection for the TM-2020.
- The TM-2025 can also monitor the voltage only of a second battery, such as a starting battery, or possibly also the input voltage of a solar array (if less than 100 volts.)
- The TM-2025 has a “simplified” level of operation suitable for most users, but can be configured for more flexibility (and complexity) where occasionally required.
- (For the technically knowledgeable only): It has a serial data output of all the “real time” data—which could be used to access data for other control or output in, for example OEM applications.
- The newer TM-2025 includes better lightning protection.
- It is easier to view and enter programmed parameters..
- It is about typically about $15 more than the TM-2020. For 48V systems it is less expensive than the TM-2020 because it does not require an extra 48 volt adapter.
There are three possible choices for the TriMetric: TM-2020, TM-2020-RV, TM-2020-A.


