Heltec BMS Low-voltage Alarm Module for NCM/LFP/LTO Batteries, 5V/12V/24V Applicable, Alarms at 4.5V/11.5V/22.5V

Heltec BMS Low-voltage Alarm Module

Product Overview

The Heltec BMS Low-voltage Alarm Module is a compact, reliable solution for monitoring battery voltage in 5V/12V/24V systems. Designed to protect NCM, LFP, and LTO battery types, it triggers audible and visual alerts when voltage drops below a safe threshold, preventing deep discharge and extending battery life.

Core Functions

Low-voltage Monitoring & AlertWhen battery voltage falls below the preset alarm value (4.5V/11.5V/22.5V), the module’s red LED lights up, and the buzzer emits a continuous alarm. Once voltage rises above the threshold, the LED turns off, and the buzzer stops.

Plug-and-Play & Adjustable Sensitivity

Out-of-the-Box Use: Preconfigured with default alarm voltage—no setup needed for immediate operation.

Custom Adjustment: Use a multimeter to fine-tune the alarm voltage. Turning the blue potentiometer clockwise increases sensitivity.

Installation & Operation

Wiring

Connect the module to your battery pack via the green terminal block:

• + terminal → Battery positive

• – terminal → Battery negative

Alarm Triggering

• 5V battery: Alarms when voltage drops below ~4.5V

• 12V battery: Alarms when voltage drops below ~11.5V

• 24V battery: Alarms when voltage drops below ~22.5V

Application Scenarios

Ideal for:

• DIY battery-powered projects (robots, IoT devices, portable electronics)

• Solar energy storage systems

• Electric vehicle (EV) auxiliary batteries

• Backup power supplies

Package Include

Trust Heltec BMS to keep your batteries safe—monitor voltage, prevent deep discharge, and ensure long-term reliability.

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