8.4.7. ATC/ATD is missing
Error #36 (ATC/ATD error) occurs when discharge current > 1.5A while ATD is disabled or when charge current > 1A while ATC is
disabled.
This can be caused by loads or chargers that are not controlled by ATC/ATD.
Make sure all loads and chargers are controlled by ATC/ATD (if not controlled by DVCC).
8.5. Battery monitor issues
8.5.1. Incomplete current reading
The negatives of all loads and charge sources in the system must be connected to the system minus side of the shunt, which is
the right side of the BMS in normal position.
If the negative terminal of a load or charging source is connected directly to the battery negative terminal or the “battery negative”
side of the shunt, its current will not flow through the battery monitor. It will therefore not be taken into account and results in a
wrong SoC reading.
8.5.2. Incorrect state of charge reading
An incorrect state of charge can be caused by a variety of reasons.
Incorrect battery settings
The following parameter(s) will have an effect on the state of charge calculations if they have been set up incorrectly:
• Battery capacity
Double check via VictronConnect app that the Battery capacity settings of the Lynx Smart BMS is correct.
Incorrect state of charge due to a synchronisation issue:
The synchronisation process is automatic and is performed each time the battery is fully charged. The battery monitor determines
that the battery is fully charged when all 3 "charged" conditions have been met. The "charged" conditions are:
• Charged voltage (Voltage)
• Tail current (% of battery capacity)
• Charge detection time (minutes)
Practical example (default battery monitor settings and a 12.8V 200Ah lithium battery) for the conditions that must be met before
synchronisation takes place:
• The battery voltage has to be above 14.0V.
• The charge current has to be less than 0.04 x battery capacity (Ah). For a 200Ah battery this is 0.04 x 200 = 8A
• Both above conditions have to be stable for 3 minutes
If the battery is not fully charged or if the automatic synchronisation does not happen, the state of charge value will start to drift
and will eventually not represent the actual state of charge of the battery.
The SoC can also be synchronised and set manually via the VictronConnect app (requires VictronConnect v5.70 or later).
8.5.3. State of charge does not increase/decrease fast enough or too fast when charging/
discharging.
This can happen when the battery monitor thinks the battery is bigger or smaller than in reality. Check if the battery capacity has
been set correctly.
8.5.4. Synchronisation issues
If the battery monitor does not synchronise automatically, one possibility could be that the battery never reaches a fully charged
state. Fully charge the battery and see if the state of charge eventually indicates 100%.
Another possibility is that the Charged voltage setting should be lowered and/or the Tail current setting should be increased.
It is also possible that the battery monitor synchronises too early. This can happen in solar systems or in systems that have
fluctuating charge currents. If this is the case, try to decrease the Charged voltage, Tail Current and Charged detection time
settings slightly.
Lynx Smart BMS
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Troubleshooting and Support
