Stop Charging to 53.2V – Protect Your Pylontech Batteries the Smart Way
The ServTec CAN-Bus Bridge is a plug and play tool designed for installers, engineers and battery specialists who want finer control over the max charge-voltage published from Pylontech US-Series batteries. It sits inline series with the CAN-Bus cable between your master battery and the inverter and lets you override the factory set "recomended charge voltage" of 53.2V via a web interface
What This Device Does
Stops your inverter from charging the batteries to 100% SOC and 53.2V, useful for inverters that lack the ability to override the recommended charge voltage published by the master battery.
- Using the built in web interface, the CVL (Charge Voltage Limit can be set to a lower value, for example 52.2V.
- Helps reduce stress on older batteries by lowering peak charge voltage.
- Keeps cell voltages within in the flat charge curve window of LFP cells and reduces cells swelling.
- Passes through all other CAN-Bus messages untouched: status, limits, SOC, SOH, alarms are still send to the inverter untouched.
- Displays live data from the master battery
What Batteries are supported
- US2000 Plus/B
- US3000 Plus/B
- US2000C
- US3000C
- US5000 / US5000B
Also compatible with other batteries and BMS devices that emulate the Pylontech 2016 LV CAN protocol (e.g., JK-BMS-based packs).
When Should You Use This Tool?
Use the bridge when you want to:
- Reduce charge voltage on ageing Pylontech modules
- Test behaviour at different CVL levels
- Evaluate BMS performance or diagnose system issues
- Avoid premature wear caused by full-voltage cycling
Features:
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Processor: Dual-core Xtensa LX7, up to 240 MHz
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Wi-Fi: 2.4 GHz, IEEE 802.11 b/g/n
- Flash Memory: 16MB
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Upgradeable by the User: Upload new firmware versions as they become available
Use only with well-maintained 15-series LiFePO₄ batteries. Do not use on damaged, swollen, unbalanced or unstable batteries.
Package Contents
- 1× CAN-Bus Bridge Unit
- 1.5 m Pylontech Battery CAN Cable
- 1.5 m Inverter CAN Cable
- 0.5m USB-C Power Cable
Power Options:
The bridge can be powered in one of the three ways:
- 5V 1A USB adapter not supplied.
- Via our 48V→5V DC-DC converter, purchase one here
- 12-24V DC Supply wired to 2 pin terminal block.
Setup Procedure
The Bridge is designed to be fully plug-and-play. It comes preconfigured with a charge-voltage limit of 52.2 V, which is still relatively high (≈3.48 V per cell). You can reduce this further to 51.8 V (≈3.45 V per cell), but note that due to the flat voltage curve of LiFePO₄ cells, SOC estimation becomes less accurate when the CVL is set too low.
- Turn off your system.
- Disconnect the CAN-bus cable currently plugged into the A/CAN port of the master battery and plug into the bridge
- Connect the bridge battery CAN-bus cable into the master battery.
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Apply power to the bride.
- Log in to the web interface to check status.
- Power on batteries and inverter.
- Check your inverter to confirm the published max-charge-voltage value has changed.
1-Year Warranty
This product includes a 1-year return-to-base warranty covering defects in materials or workmanship.
- The warranty covers manufacturing defects only.
- It does not cover damage caused by incorrect installation, misuse, modification, exposure to unsuitable environments, or operation outside the guidance provide
Need Help With Compatibility or Setup?
Our UK-based support team can help verify inverter pinouts, alternative BMS compatibility, and wiring requirements. Email us at support@servtec.co.uk
Further Reading:
Manual
How Victron deal with this issue within their Cerbo GX.
