1. Уводзіны
This manual provides essential information for the safe and efficient use of your DALY Smart BMS 4S 12V 120A LiFePO4 PCB Protection Board. Please read these instructions carefully before installation and operation to ensure optimal performance and longevity of your battery system.

Figure 1: DALY Smart BMS 4S 12V 120A LiFePO4 PCB Protection Board
2. Асаблівасці прадукту
- Комплексная абарона: Overcurrent, Overcharge, Overdischarge, Short circuit, and Temperature protection to maximize battery performance and extend lifetime.
- Палепшаная трываласць: Double protection via injection patent technology and patent shell, offering waterproof, dustproof, shockproof, and anti-static properties.
- Высакаякасныя кампаненты: Utilizes pressure-resistant and durable materials with high acquisition accuracy.
- Разумны маніторынг: Check battery status and modify parameters at any time through the Bluetooth app or PC Software (UART).
- Лёгкая ўстаноўка: Designed for straightforward setup.
- Гарантыя якасці: ISO/FCC/RoHS/PSE/CE APPROVED for reliable performance.

Figure 2: Visual representation of the 12 protection functions.
3. Змесціва ўпакоўкі
The DALY Smart BMS 4S 12V 120A package includes the following items:
- 3.2V Lifepo4 BMS (1 unit)
- Bluetooth Module (1 unit)
- NTC sensor (1 unit)
- Sampling cable (1 unit)
- UART cable (1 unit)
- Інструкцыя па эксплуатацыі (1 адзінка)

Figure 3: DALY Smart BMS and included accessories.
4. Тэхнічныя характарыстыкі
| Спецыфікацыя | Каштоўнасць |
|---|---|
| Марка | DALY |
| Назва мадэлі | lifepo4 |
| Колер | Разумная BMS |
| Уключаныя кампаненты | PCB BMS |
| тtage | 12 вольт |
| Выхад Voltage | 12 вольт |
| UPC | 714216177905 |
| Вытворца | Dongguan Daly Electronics Co., Ltd |

Figure 4: DALY Smart BMS dimensions.
Detailed Product Parameters (LiFePO4 4S BMS)

Figure 5: Detailed specifications for LiFePO4 4S BMS (Part 1).

Figure 6: Detailed specifications for LiFePO4 4S BMS (Part 2).
Detailed Product Parameters (LiFePO4 4S Smart BMS)

Figure 7: Detailed specifications for LiFePO4 4S Smart BMS (Part 1).

Figure 8: Detailed specifications for LiFePO4 4S Smart BMS (Part 2).
5. Тэхніка бяспекі
- Always disconnect the balance wires and BMS connection port before welding.
- Ensure all battery cells are balanced and at a similar voltage before connecting to the BMS.
- Verify correct wiring polarity (B- and B+) to prevent damage.
- Avoid short circuits during installation and operation.
- Do not expose the BMS to extreme temperatures or moisture beyond its specified operating range.
- If you are unsure about any step, consult a qualified professional or DALY customer service.
6. Installation and Wiring Instructions
Proper installation and wiring are critical for the safe and effective operation of your DALY Smart BMS. Follow these steps carefully.
6.1. Prepare Materials
Before starting, gather the necessary tools and materials:
- Soldering machine (suggested temperature: 662°F/350°C)
- Нажніцы
- Двухбаковы скотч
- Tin wire
- Мультыметр
- DALY matching balance wires
Video 1: Guide on preparing materials before DALY BMS wiring.
6.2. Determine SampЛінг Акуляры
Accurately identify the sampling points on your battery pack. This is crucial for correct voltagе маніторынг.
Video 2: Detailed guide on determining DALY BMS sampлінг -пойнт.
6.3. Wiring the Battery Pack
Follow the wiring diagram and video instructions to connect the balance leads to your battery pack. Ensure all connections are secure and correct.

Figure 9: Wiring diagram for DALY Smart BMS to a LiFePO4 battery pack.
Video 3: Step-by-step guide for DALY BMS wires welding.
6.4. Pre-Connection Voltagе тэст
Before connecting the balance leads to the BMS, test each cell's voltage to ensure they are within the acceptable range and balanced. This prevents damage to the BMS.
Video 4: Instructions on testing battery voltage before connecting with DALY BMS.
6.5. BMS Connection and Activation
Once wiring is complete and verified, connect the balance leads to the BMS. The BMS may require activation to begin normal operation.
Video 5: Guide on connecting and activating the DALY Smart BMS.
7. Operation (Smart Features)
The DALY Smart BMS allows for convenient monitoring and parameter modification via a Bluetooth app or PC software.
7.1. Bluetooth App Connection
Connect your smartphone to the BMS via the Bluetooth module to access real-time battery status and adjust settings.
Video 6: Demonstrates DALY Smart BMS UART RS485 CAN with cooling fan and Bluetooth connectivity.

Малюнак 10: Выпample of the DALY Smart BMS app interface showing battery status and parameter settings.
8. Выпраўленне непаладак
If you encounter issues with your DALY Smart BMS, refer to the following common problems and solutions. For more complex issues, contact customer support.
8.1. Common Wiring Errors
Incorrect wiring is a frequent cause of BMS malfunction. Review the wiring instructions and the video below to identify and correct potential errors.
Video 7: Highlights 5 common errors during DALY BMS wiring and how to avoid them.
8.2. BMS Not Activating
If the BMS does not activate after initial connection, ensure all cells are properly balanced and the activation procedure (e.g., connecting a charger) has been followed correctly. Refer to Video 5 for activation steps.
9. Гарантыя і падтрымка
Your DALY Smart BMS comes with a 1-year warranty. For any technical assistance, troubleshooting, or inquiries, DALY offers 24-hour one-on-one customer service and lifetime technical support.
Please refer to the contact information provided with your product or visit the official DALY webсайт для падтрымкі.