cryptom avatar image
cryptom asked

Pylontech Modbus Addressing Recovery

Hello everyone,

I'm doing a large installation that consists of 242 Pylontech US5000 batteries. For maintenance purposes, it seems important to us to be able to act quickly on a defective battery or one that has a too high temperature for example. Unfortunately, we have not yet been able to find a solution that would accurately indicate a defective battery.

Recently I noticed that the remote console was indicating the address of the coldest/hottest battery or the lowest/highest voltage battery as shown in the attached picture.

battery-addressing.pngMax cell temperature : Battery 0101 - 19°C

If the Cerbo GX indicates these addresses, there must be a way to retrieve all the battery addresses. In this way we will be able to associate the address of the battery with its number and its location in the battery bank.

For the communication with the batteries we will use several LV Hubs. The next step will be to ask Pylontech how the addressing of the batteries is distributed.

Do you have any idea how I can enter in the Cerbo GX and retrieve the address of a battery? I will also need to find a way to display the temperature status of each battery in the VRM...

I have never tried to get the Modbus address of the batteries so I don't know yet the tool to use for that... Can you direct me to the method?

I saw that there is the Node-Red tool but I don't know if it will be able to help me and I haven't dug into the possibilities of this tool yet.


Lithium BatteryPylontechModbus TCP
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ponzoa avatar image ponzoa commented ·
I would be really interested in understanding your DC Bus design and what you will be using. There are a lot of amps in 242 US5000C.
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3 Answers
gunzenbomz avatar image
gunzenbomz answered ·

24 batterys or 242. You could try the ebay available

SERVTEC Diagnostic Console Cable Pylontech US2000, US3000, US5000 Battery View

24 batteries would cost £40,000 & £400,000 for running a small town off grid??

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Guy Stewart (Victron Community Manager) avatar image
Guy Stewart (Victron Community Manager) answered ·

Hi @Cryptom

There is no way to retrieve all battery addresses from the GX device. This is not a part of our BMS-Can specification.

The specification only receives from the battery BMS what you already see when you open the GX. The GX is not receiving all temps, voltages and addresses from the batteries and calculating which is the highest and lowest.

The BMS (on the battery side) is receiving that individual module data, and then only sending the highest and lowest to the GX device via the BMS-Can connection. What you see is all that we have access too.

For any further details you'll need to work directly with the BMS via Pylontech's tools (and another interface).

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cryptom avatar image cryptom commented ·

Hi @Guy Stewart (Victron Community Manager),

Thank you very much for your answer. I will contact Pylontech to get this information and create a superior level to the Victron monitoring.

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hominidae avatar image
hominidae answered ·

...the pattern behind the numbering from the Pylontech BMS could possibly this:

<group #id [01..0X]><batteryID in group 0X>, where the master battery in each group is 01.

So module 0101 is the master battery in group 01 and 0106 is the module #6 in the same group.

This is based on my empiric observation, having only one group (no LV hub) with 6 modules stacked up in a rack.

When observing the temps in that stack/group, I find the ones in between of higher temps than the ones on the outer edges ... 0101 and 0106 in my case, with 0106 being always the lowest temp, as it sits at the bottom in the rack and the master 01 sitting on the top end in the rack.

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