A quick and easy framework for data-logging and interfacing with a Tristar-MPPT-45 Solar Controller over a serial connection.
You can download the library through pip with pip install mppt_reader
To directly interface with the solar controller, use the MPPTReader class. It provides access to most variables, even if not it is easy to add.
Additionally, if you want to log certain variables, use the MPPTLogger class and pass it a MPPTReader instance.
This library allows for you to change regulations in the solar controller, which relate to voltage targets. To do so, you need to set a value.
Initially, the override is unlocked, which means that the value you set isn't being written. To have your value written, you need to call .lock() on the override.
You can change the value without unlocking, but its important to remember that you are in control of the value until you call .unlock(). After unlocking, it returns control back to the solar controller.
If you were to lock an override and your software crashes, the values will still be written to the solar controller, but after 60 seconds - a fault is thrown and values are taken over by the solar controller again.
For this reason, you can't set update_interval of MPPTReader greater than 55.
from mppt_reader.reader import MPPTReader
from mppt_reader.logger import MPPTLogger
from mppt_reader.constants import Variable
reader = MPPTReader("COM3")
# You must provide variables, but file_name will default to the current date and time. Update interval is normally 1 second.
logger = MPPTLogger(reader, variables=[Variable.BATTERY_VOLTAGE, Variable.ARRAY_VOLTAGE], file_name="output", update_interval=2)
# Now it will be logging all variables every second to output.csv and you can still mess with the MPTTReader
reader.overrides.battery_voltage_regulation.set_value(11)
# The value is set, but is not currently controlling the actual voltage regulation.
reader.overrides.battery_voltage_regulation.lock()
# Now, it will start updating with your given value and you can change it.
reader.overrides.battery_voltage_regulation.set_value(10)
# If you set too high or a too low value, you could cause a fault!
reader.overrides.battery_voltage_regulation.unlock()
# Now it will return control to the slave, make sure to unlock or you will just keep the same value forever.