Temperature Compensation Setting Incorrect; Temperature Difference Between Solar Charger And Battery - Victron energy MPPT 150/70 Manual

Battery cable voltage drop check
Using the VictronConnect app or a multimeter, measure the voltage on the battery terminals of the solar
charger.
Step 2
Measure the battery voltage on the terminals of the battery using a multimeter.
Step 3
Step 4 Compare the two voltages to identify any voltage difference.
VE.Smart Networking can assist in mitigating a small cable voltage drop. However, for a substantial voltage drop, there may be
an issue with the wiring between the solar charger and the battery, which requires rectification before proceeding.
In a VE.Smart Network a Smart Battery Sense
VE.Smart Networking to the solar charger. If the battery voltage is less than the solar charge voltage, the solar charger will
increase its charge voltage to compensate for (small) voltage losses.

8.6.4. Temperature compensation setting incorrect

Improperly configuring the temperature compensation coefficient can lead to either undercharged or overcharged batteries.
Note that temperature compensation is typically applicable only to lead-acid batteries.
To determine the correct temperature compensation coefficient for your battery, consult the battery documentation. If uncertain,
use the default value of -64.80mV/°C for lead-acid batteries, and for lithium batteries, disable the temperature compensation
setting.

8.6.5. Temperature difference between solar charger and battery

For proper operation, it is crucial that the ambient temperatures of both the battery and the solar charger are equal, especially if
the solar charger is not receiving battery temperature data.
Note that this chapter does not apply if the solar charger is connected to a VE.Smart Network with a battery
temperature measurement or is equipped with a temperature sensor.
At the beginning of the day, as soon as power is generated by the solar array, the solar charger will measure the ambient
temperature and use it to temperature-compensate the charge voltage.
During the float stage, the solar charger will re-measure the ambient temperature and adjust the voltages accordingly.
Large differences in ambient temperature between the solar charger and the battery can lead to improper charging voltages for
the battery.
For instance, if the solar charger is placed near a sunlit window while the batteries are located on a cold concrete floor in the
shade, this temperature discrepancy can affect the charging process.
To ensure optimal performance, always ensure that the ambient conditions are equal for both the solar charger and the battery.
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MPPT solar charger manual
or battery monitor measures the battery terminal voltage and transmits this via
Troubleshooting