1. Introduction
This manual provides instructions for the HP 45 Black Ink Cartridge (model 51645A). This cartridge is designed to deliver consistent print quality and reliability when used with compatible HP printers. It features pigment ink technology for sharp black text and graphics.
The HP 45 Black Ink Cartridge is engineered to work with HP printers to provide consistent quality, reliability, and value. It offers an approximate yield of 930 pages.

The HP 45 Black Ink Cartridge is supplied in a sealed package, ensuring product integrity until use.
2. Compatibility
The HP 45 Black Ink Cartridge is compatible with a range of HP printer models. Refer to the list below to confirm compatibility with your device:
- HP DeskJet Series: 710, 712, 720, 722, 820, 830, 832, 850, 855, 870, 880, 882, 890, 895, 930, 932, 935, 950, 952, 960, 970, 990, 995, 1000, 1100, 1120, 1220, 1600, 6122, 6127, 9300
- HP DesignJet Series: 700, 750, 755
- HP OfficeJet Series: G55, G85, G95, K60, K80, R40, R60, R80, T45, T65
- HP OfficeJet Pro Series: 1150, 1170, 1175
- HP PhotoSmart Series: P1000, P1100, 1115, 1215, 1218, 1315
- HP Color Copier Series: 110, 120, 140, 145, 150, 155, 160, 170, 180, 190, 210, 260, 270, 280, 290
- HP Fax Series: 1220

This image displays a comprehensive list of HP DeskJet, DesignJet, OfficeJet, PhotoSmart, Color Copier, and Fax series printers that are compatible with the HP 45 Black Ink Cartridge.
3. Installation
Follow these general steps to install the HP 45 Black Ink Cartridge into your compatible HP printer. For specific instructions, always refer to your printer's user manual.
- Ensure your printer is powered on and open the printer's access door to the cartridge area.
- Wait for the print carriage to move to the center of the printer.
- Carefully remove the old ink cartridge by pressing down on it or pulling it out, depending on your printer model.
- Unpack the new HP 45 Black Ink Cartridge. Remove any protective tape or plastic from the cartridge, being careful not to touch the electrical contacts or ink nozzles.
- Insert the new cartridge into the empty slot. The cartridge is designed for easy drop-in/snap-out action for quick and clean replacement. Push firmly until it clicks into place.
- Close the printer's access door. The printer may perform an alignment process automatically.
4. Operation
Once installed, the HP 45 Black Ink Cartridge is ready for use. The cartridge provides high-density pigmented ink, producing sharp black text and graphics for various printing needs.

This image highlights the print quality achievable with HP ink, showcasing the clarity of black text and the vibrancy of colors in printed documents and images.

Printed documents featuring sharp text and brilliant colors are shown, demonstrating the output quality of the HP 45 Black Ink Cartridge for various applications.

An HP printer is depicted in operation, producing documents that exemplify consistent quality, reliability, and value, as engineered by HP.
The cartridge body includes an easy-to-view ink level indicator, allowing users to monitor ink supply.
5. Maintenance
Proper maintenance ensures optimal performance and longevity of your ink cartridge and printer.
- Storage: Store unused cartridges in their original sealed packaging at room temperature. Avoid extreme temperatures and direct sunlight.
- Handling: Avoid touching the electrical contacts or print nozzles on the cartridge to prevent clogs or damage.
- Printhead Cleaning: If print quality degrades (e.g., streaks, faded prints), your printer's software may offer a printhead cleaning utility. Consult your printer's manual for instructions on how to perform this maintenance.
6. Troubleshooting
If you encounter issues with printing, consider the following common troubleshooting steps:
- Poor Print Quality: Check the ink level indicator. If ink is low, replace the cartridge. Run the printhead cleaning utility from your printer's software. Ensure you are using appropriate paper for your print settings.
- Streaks or Missing Colors: This often indicates clogged nozzles. Perform a printhead cleaning cycle. If the problem persists, try a deeper cleaning cycle if available in your printer's software.
- Cartridge Not Recognized: Ensure the cartridge is correctly seated in its slot. Remove and reinsert it. Check for any protective tape that may still be covering the electrical contacts. Clean the electrical contacts on the cartridge and in the printer with a lint-free cloth if necessary.
- Error Messages: Refer to your printer's display or software for specific error codes and consult your printer's user manual for solutions.
For further assistance, consult your HP printer's specific user manual or visit the HP support website.
7. Specifications
| Feature | Specification |
|---|---|
| Model Number | 51645A (also 51645AE) |
| Ink Color | Black |
| Printer Ink Type | Pigment |
| Approximate Page Yield | 930 pages |
| Item Weight | 4.2 ounces (0.12 Kilograms) |
| Product Dimensions | 4.56 x 6.2 x 1 inches |
| Maximum Black and White Print Resolution | 600 x 600 DPI |
| Included Components | Inkjet Cartridges |
| Material Type | Ink |
| Total Recycled Content Percentage | 80% (of the cartridge) |
8. Safety Information
This product is an ink cartridge. Handle with care to avoid ink spills. Keep out of reach of children. Do not ingest ink. In case of contact with skin or eyes, rinse immediately with plenty of water. If irritation persists, seek medical attention.
9. Warranty and Support
The HP 45 Black Ink Cartridge comes with a limited warranty. For details regarding the warranty period and coverage, please refer to the documentation included with your product or visit the official HP support website.
Original HP printer ink and toner cartridges are designed to provide dependable performance, consistent page yields, and quality results. Using non-HP cartridges may affect print quality and printer performance, and could potentially void your printer's warranty.

This image illustrates the security features integrated into HP cartridges, designed to protect the printer and data through tamper-resistant chips and firmware.
10. Recycling Information
HP is committed to environmental responsibility. This ink cartridge contains recycled content, with 88% of Original HP Ink Cartridges containing recycled plastic. HP offers a recycling program for used cartridges.

A hand is shown placing an empty ink cartridge into a designated recycling bag, demonstrating the ease of participating in HP's recycling program. For more information on recycling, visit hp.com/recycle.

This image shows a pile of recycled plastic flakes alongside HP ink cartridges, emphasizing that a significant percentage of original HP ink cartridges contain recycled plastic.

The image visually represents the environmental impact of HP's recycling efforts, showing plastic bottles that have been upcycled into new Original HP Ink Cartridges.