IWISS SN-2549
IWISS iCrimp SN-2549 Ratcheting Wire Crimping Tool User Manual
Model: SN-2549
1. Introduction
This manual provides detailed instructions for the safe and effective use of the IWISS iCrimp SN-2549 Ratcheting Wire Crimping Tool. This tool is designed for crimping uninsulated open barrel terminals across various pitch sizes, including JST, Dupont, and Molex connectors. Please read this manual thoroughly before operation to ensure proper usage and to prevent damage to the tool or injury.
2. Safety Information
Always observe the following safety precautions when using the crimping tool:
- Wear appropriate personal protective equipment, such as safety glasses, to protect against flying debris.
- Ensure the work area is clean, well-lit, and free from obstructions.
- Do not use the tool for purposes other than its intended use (crimping open barrel terminals).
- Keep hands and fingers clear of the crimping jaws during operation to avoid pinching.
- Inspect the tool for any damage before each use. Do not use a damaged tool.
- Keep out of reach of children.
3. Product Overview
The IWISS iCrimp SN-2549 features a robust design for reliable and consistent crimps. Key components include:
- Ratcheting Mechanism: Ensures a complete crimp cycle for secure connections.
- EDM Processed Jaws: High-precision jaws for accurate and even crimping.
- Non-Slip Handles: Ergonomically designed for comfortable and secure grip during operation.

Figure 3.1: Overview of the IWISS iCrimp SN-2549 Ratcheting Wire Crimping Tool.

Figure 3.2: Detailed features including the ratcheting mechanism, EDM processed jaws, and non-slip handles.

Figure 3.3: Close-up view of the precision EDM jaws, designed for accurate crimping.
4. Operating Instructions
Follow these steps for proper crimping of open barrel terminals:
- Strip the Wire: Carefully strip the insulation from the end of the wire to the appropriate length for your terminal. The exposed conductor should match the length of the terminal's conductor crimp section.
- Position the Terminal: Open the crimping tool and select the correct crimp slot for your terminal size. Insert the open barrel terminal into the chosen slot. Partially close the handles until the terminal is held securely in place by the tool's ratcheting mechanism.
- Insert the Wire: Insert the stripped wire into the terminal. Ensure the conductor is fully seated within the conductor crimp section and the insulation is positioned correctly within the insulation crimp section.
- Crimp the Terminal: Squeeze the handles of the crimping tool firmly until the ratcheting mechanism completes its cycle and releases. This ensures a full and consistent crimp.
- Inspect the Crimp: Remove the crimped terminal and inspect it. The conductor should be securely crimped, and the insulation should be held firmly without being cut or damaged. Gently tug on the wire to verify the connection's strength.

Figure 4.1: Visual guide to the four-step crimping process.
5. Applications
The IWISS iCrimp SN-2549 is suitable for a wide range of electrical and electronic projects, including:
- Creating custom wiring harnesses for JST, Dupont, and Molex connectors.
- Repairing or modifying wiring in rechargeable battery packs and battery balancers.
- Connecting components in 3D printers and other hobby electronics.
- Working with radio-controlled (RC) servos and other RC equipment.
- Prototyping circuits on breadboards.

Figure 5.1: Examples of common applications for the crimping tool.
6. Maintenance
To ensure the longevity and optimal performance of your crimping tool:
- Keep the tool clean and free from dirt, dust, and debris. Wipe it down with a clean, dry cloth after each use.
- Periodically apply a light coat of machine oil to the pivot points and moving parts to ensure smooth operation and prevent rust.
- Store the tool in a dry environment to prevent corrosion.
- Do not attempt to disassemble the tool beyond routine cleaning and lubrication.
7. Troubleshooting
If you encounter issues with your crimping tool, consider the following:
- Poor Crimp Quality:
- Ensure the correct crimp slot is selected for the terminal size.
- Verify the wire is stripped to the correct length and fully inserted into the terminal.
- Confirm the ratcheting mechanism completes its full cycle.
- Tool Jams:
- Check for any foreign objects or debris in the jaws.
- Ensure the terminal is correctly aligned before crimping.
- Stiff Operation:
- Apply a small amount of lubricant to the pivot points.
- Clean any accumulated dirt or grime from the moving parts.
If problems persist, contact customer support.
8. Specifications
| Attribute | Detail |
|---|---|
| Model | SN-2549 |
| Brand | IWISS |
| Crimping Capacity | AWG28-18 (0.08-1.0mm²) |
| Compatible Terminals | JST ZH 1.5mm, PH 2.0mm, XH 2.5mm, VH 3.96mm, JWPS 4.0mm Pitch, Dupont 2.54mm Pitch Open Barrel Terminals |
| Tool Type | Ratcheting Wire Crimping Tool |
| Handle Material | Ergonomic, Multicolor |
| Item Weight | 13.8 ounces (approx. 391 grams) |
| Product Dimensions | 7.48 x 2.56 x 1.1 inches |
| Manufacturer | ZHEJIANG IWISS ELECTRIC CO.,LTD |
9. Warranty and Support
For warranty information or technical support, please refer to the official IWISS website or contact their customer service directly. Keep your purchase receipt for warranty claims.
IWISS Customer Service: Visit IWISS Contact Page
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