1. Introduction
This manual provides essential information for the safe and effective use of your ExpertPower 12 Volt 3.3 Amp Hour Sealed Lead Acid Battery (Model EXP1233). This battery is designed as a direct replacement for various APC Back-UPS ES 350 series models, including BE350E, BE350C, BE350R, and BE350U. Please read this manual thoroughly before installation and operation.

Figure 1: ExpertPower 12V 3.3Ah Sealed Lead Acid Battery (Model EXP1233)
This image displays the ExpertPower 12V 3.3Ah Sealed Lead Acid Battery, highlighting its compact black casing and F1 terminals. The label on the battery provides key specifications and safety warnings.
2. Important Safety Information
WARNING: Failure to follow these safety instructions could result in fire, explosion, electric shock, or other injury.
- Risk of fire, explosion, or burns: Do not short the battery terminals.
- Do not disassemble, heat above 40°C (104°F), or incinerate.
- Do not charge the battery in a sealed container.
- Keep away from sparks or open flame.
- Electrolyte (Acid) Contact: Flush with water at once if contaminated with electrolyte (acid).
- Recycling: Rechargeable batteries must be recycled. Refer to local regulations for proper disposal.
- Keep out of reach of children.

Figure 2: Quality and Safety Certifications
This image illustrates the quality and safety standards met by ExpertPower batteries, including ISO certifications and UL recognition, ensuring product reliability and user safety.
3. Setup and Installation
The ExpertPower EXP1233 battery is designed for simple, plug-and-play installation into compatible APC Back-UPS ES 350 series units. Ensure your UPS unit is unplugged from the wall outlet and turned off before beginning the installation process.
- Locate Battery Compartment: The battery compartment is typically located on the bottom or side of your APC Back-UPS ES 350 unit. Refer to your UPS manual for exact location.
- Remove Old Battery: Open the battery compartment cover. Carefully disconnect the existing battery by pulling off the red (positive) and black (negative) terminal connectors. Remove the old battery from the compartment.
- Prepare New Battery: The ExpertPower EXP1233 battery comes fully charged. Ensure the F1 terminals are clear and ready for connection.
- Connect New Battery: Connect the red cable from the UPS to the red (positive) terminal of the new battery. Connect the black cable from the UPS to the black (negative) terminal of the new battery. Ensure connections are secure.
- Insert New Battery: Carefully slide the new battery into the compartment.
- Close Compartment: Replace the battery compartment cover, ensuring it is securely latched.
- Power On: Plug the UPS unit back into the wall outlet and turn it on. The UPS should now operate normally without any "replace battery" indicators or beeping.
Video 1: Overview of a 12V 3.3Ah Deep Cycle Battery
This video provides a general overview of a 12V 3.3Ah deep cycle battery, similar in type to the ExpertPower EXP1233. It highlights key features and potential applications, offering visual context for the product.
Video 2: Casil 12V 3.3Ah Battery - CA1233
This video showcases the Casil 12V 3.3Ah battery, model CA1233, which shares similar specifications with the ExpertPower EXP1233. It demonstrates the battery's physical characteristics and potential uses in home security alarm systems.
4. Operating Your UPS with the New Battery
Once installed, the ExpertPower EXP1233 battery will provide reliable backup power to your APC Back-UPS ES 350 unit. In the event of a power outage, the UPS will automatically switch to battery power, allowing connected devices to continue operating for a limited time. This provides an opportunity to safely shut down equipment, preventing data loss or damage.
The battery is a sealed lead-acid type, designed for consistent voltage and long cycle life. It is maintenance-free and non-spillable.
5. Maintenance and Care
- Battery Lifespan: Sealed lead-acid batteries typically have a lifespan of 3-5 years under normal operating conditions.
- Storage: Store the battery in a cool, dry place. Do not store the battery in temperatures over 50°C (122°F).
- Cleaning: Keep battery terminals clean and free from corrosion. Use a dry cloth to wipe down the battery if needed.
- Recycling: When the battery reaches the end of its useful life, it must be recycled properly. Do not dispose of it in household waste. Many electronics stores or recycling centers accept lead-acid batteries.
6. Troubleshooting
- UPS Beeping Continuously: If your UPS is beeping and indicating a "replace battery" warning after installing the new battery, ensure all connections are secure. If the issue persists, verify the battery is fully charged (it comes pre-charged, but a short charge cycle might be needed if stored for a long time) and that it is the correct model for your UPS.
- Battery Not Fitting: Double-check the dimensions of your old battery against the specifications of the EXP1233. While designed for APC Back-UPS ES 350 series, slight variations in UPS models or older units might exist. The EXP1233 uses F1 terminals (0.187 inches wide). Some UPS models might require F2 terminals, which are slightly larger. Adapters may be available if needed, but ensure compatibility before purchase.
- Reduced Runtime: If the UPS runtime is significantly shorter than expected, ensure the battery has had sufficient time to fully charge after installation. Over time, all batteries will experience reduced capacity.
7. Product Specifications
| Feature | Detail |
|---|---|
| Brand | ExpertPower |
| Model Number | EXP1233 |
| Battery Type | Sealed Lead Acid (SLA) |
| Voltage | 12 Volts |
| Amperage | 3.3 Amps |
| Capacity | 3.3 Amp Hour (20 Hour Rate) |
| Terminals | F1 Terminals |
| Dimensions (L x W x H) | 5.28 x 2.63 x 2.42 inches (13.4 x 6.7 x 6.1 cm) |
| Item Weight | 2.8 pounds (1.27 kg) |
| Compatibility | APC Back-UPS ES 350, BE350E, BE350C, BE350R, BE350U |
| Safety Rating | DOT Certified, UL Recognized |

Figure 3: Technical Specifications Overview
This image provides a visual summary of the ExpertPower EXP1233 battery's technical specifications, including weight, voltage, watt-hour, amp-hour, and F1 terminal type.

Figure 4: Battery Dimensions
This diagram illustrates the precise dimensions of the ExpertPower 12V 3.3Ah SLA battery, showing its length, width, and height in both inches and centimeters, crucial for ensuring proper fit.
8. Warranty Information
ExpertPower batteries come with a limited warranty. For specific details regarding the warranty period and terms, please refer to the warranty information included with your product packaging or contact ExpertPower customer support.
9. Customer Support
For any questions, technical assistance, or support needs, please contact ExpertPower customer service. Our support team is available to assist you.
- Operating Hours: Monday - Friday, 9 AM - 6 PM PST
- Contact Information: Please refer to the product packaging or the official ExpertPower website for the most current contact details.

Figure 5: ExpertPower Customer Support
This image highlights the availability of ExpertPower customer support, indicating operational hours and the commitment to customer satisfaction.





