123SmartBMS G3 4S, 2x I-sensor 2021


123SmartBMS gen3 is a complete set for 4 cells, 2 dual range current sensors, with Bluetooth. 

123SmartBMS gen3 is an easy to use yet advanced, modular BMS to keep your lithium batteries in perfect condition, increasing the lifespan of the battery pack.

Easily connect your phone to the BMS to see and adjust relevant information. 

Get it on Google Play Download on the Apple Store

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The BMS measures important data like cell voltages, cell temperatures and in- and outgoing currents with the two included highly accurate, dual range current sensors. By using two current sensors you can measure the incoming and outgoing currents independently and read them in the app. If you only want to be able to read the charge status of your battery (ie the sum of the incoming and outgoing currents) then the 123SmartBMS G3 4S, 1x I-sensor 2021 is the right choice.

The system balances all cells to the same voltage during charging.

The two signal relays with galvanically isolated contacts can be used to switch on/off relays of the current to chargers and/or user. This protects your battery against overcharging, deep discharge and overheating.

New in gen3:

  • Highly accurate SOC, dual range current sensors to measure a wide range of currents up to 500A.
  • Over the air software update.
  • LTO compatible, Operates on cell voltages between 1.5V and 5.0V, bypass adjustable between 1.9V - 4.9V.
  • Error history to see when, what cell and which error occurred.
  • SOC logging of the last week.
  • More accurate temperature measurement near cell pole.
  • Easier configuration.

Main features:

  • Modular BMS which can be used from 2 to 255 cells.
  • Can be mounted directly on the cells, no external controller needed.
  • Two signal relays with potential free contacts which indicate the system is allowed to load and/or charge. This can be used to switch enable/disable signals or power relays.
  • Possible to use two current sensors instead of one to see consumed and produced energy independently.
  • Bluetooth 4.0 LE to see relevant data on your portable device.
  • Compatible with almost any cell chemistry including LTO, LiFePO4, NMC and NCA.
  • 1A balancing current. Even big cell capacities will be balanced.

Package content:

  • IN Cell Board
  • OUT Cell Board
  • 2 Between Boards
  • 2 Dual range current sensors 500A (diameter: 22mm, surface: 380mm2)
  • Piece of 0,75 mm² wire for the interconnections
  • Connector unlock tool

Installation manual:

Read the installation manual carefully. It contains further information about the BMS and is step-by-step clearly illustrated how you connect and configure the system. It also describes what information you can see using the app and which values you can set.

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Price €81.82
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