High Voltage / Relay BMS

3-32S Smart Relay BMS 96V 500A with BT/CAN/RS485

The smart relay BMS can be one of the perfect solution for large vehicle starting power, engineering vehicle, low speed four-wheel vehicle, RV or any other device you want to place it in.

It supports 500A continuous current output, and the peak current can reach 2000A. It is not easy to be heated or damaged. If damaged, the main control will not be affected. You only need to replace the relay to reduce maintenance costs. You can also develop your own application system according to your own needs. We can provide BMS interface communication protocol.

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Product Detail

Product Tags


  • 3-4S
  • 6-8S
  • 10-24S
  • 25-32S

Product Information

Brand Name: HeltecBMS
Material: PCB board
Origin: Mainland China
Warranty: One year
MOQ: 1 set
Battery Type: NCM/LFP/LTO


  • Customized logo
  • Customized packaging
  • Graphic customization


1. Smart Relay BMS *1set. (Other parts according to your needs)
2. Anti-static bag, anti-static sponge and corrugated case.

Purchase Details

  • Shipping From:
    1. Company/Factory in China
    2. Warehouses in United States/Poland/Russia/Brazil
    Contact Us to negotiate shipping details
  • Payment: TT is recommended
  • Returns & Refunds: Eligible for returns and refunds


  • Built-in BT module:
    view battery parameters on the phone (Android only, IOS is under development).
  • Various protection functions:
    overcharge protection, over discharge protection, over current protection, balance protection, short circuit protection, BMS low voltage sleep, NTC temperature control protection, etc.
  • The application can adjust hardware and software parameters.
  • Static balance:
    setting the battery voltage difference between 0.02V-0.05V, it will automatically turn on the balance function.
  • Protection parameter settings and modifications:
    It can modify the high and low temperature of charging and discharging, over-voltage and under-voltage of battery packs and of individual batteries, short-circuit and voltage difference, and balance voltage. It can also reset and restore factory settings.

Example of Package Details

32S 100A Split port BMS include:

  • 1* 25-32S BMS with harness(around 800mm)
  • 1* Hall
  • 3* Relay
  • 1* Pre-amp resistance
2-32S Smart Relay detail03


  • 1* UART Support Modbus protocol
  • 1* Isolated RS485 interface, support Modbus protocol
  • 1* Independent CAN2.0B interface

DC relay

2-32S Smart Relay detail02Customers need to equip their own relays, select the required current, and support the choice to cut off the positive or negative wire. Various mainstream relays can be used, with convenient selection and more stable use.

It can control 2-4 relays to control power off, connect with Hall sensor, shunt, and charge and discharge different ports.

The relay is a main circuit switch. You can choose different currents, but the maximum current does not exceed 500A. It is recommended that the working power consumption be less than 500mA. BMS only provides 12V control voltage to control the introduction of relay. (Current relay power consumption: 250mA.)

PC software

Our development and adaptation of the BMS PC software supports monitoring parameters, modify the configuration and other functions. Notice: It must be used with UART or RS485 module to USB. Please contact us to purchase if you need it.


The product has 3-4 temperature sensors with a length of 500mm. It can collect current battery temperature information.

Product Parameters

Technical Index



Overcharge protection



Charge release protection



Charge detection delay


Discharge and power failure protection



Discharge release protection



Discharge detection delay


Charging current

number of strings*4.2V

number of strings*3.6V

Continuous current


Overcurrent protection

200A *3-8 Times

Overcurrent detection delay


Overcurrent release protection

disconnect the load

Short-circuit protection

load short-circuit through the protection board
(no direct short-circuit BMS)

Charging and discharging temperature


Reset social equipment


Working temperature

-20°C ~85°C

Opening conditions of balanced pressure difference


Dynamic self-consumption


Static self-consumption


SOC estimation difference


Balance current


Single string voltage collection range


Single string voltage collection error

±10mV FS

Total battery voltage collection range

depends on specifications

Total battery voltage collection error

±100MV FS

Charge and discharge current collection range


Charge and discharge current collection error


NTC temperature control collection range


NTC temperature control check error


2-32S Smart Relay detail04
2-32S Smart Relay detail05
2-32S Smart Relay detail06

* We keep upgrading products to meet requirements of our clients, please contact our sales person for more accurate details.


1. Mobile APP is not available for BMS more than 32S and Master-slave design.
2. If you want to use it with RS485/CAN, you need to use a serial port module as below:

RS485 To USB Module

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