Introduction
The AngelaKerry EF851S is a wireless pet containment system utilizing GPS positioning technology. This system is designed to provide a safe and adjustable boundary for your dog within an outdoor area, offering greater accuracy and stability compared to traditional radio-frequency fences. It aims to prevent accidental warnings and injuries by minimizing interference from metal or obstacles.

Image: The AngelaKerry EF851S GPS Dog Fence System, featuring the blue collar receiver and a small dog wearing a similar collar.
Key Features:
- Adjustable circular boundary radius from 20 meters (22 yards) to 800 meters (850 yards).
- Covers an area ranging from 0.3 acres to 496 acres.
- Rechargeable and waterproof collar receiver with beep and static correction functions.
- Five levels of static correction to suit various dog sensitivities.
- All functions are integrated into the collar for ease of use and portability.
- Suitable for dogs weighing between 15 pounds and 120 pounds.
- Automatic protection design limits stimulation duration and suspends operation in the absence of GPS signals.
Package Contents
Verify that all items listed below are included in your package:
- 1 x Pet Receiver (GPS Collar)
- 1 x TPU Belt (Collar Strap)
- 4 x Metal Contact Points (two short, two long)
- 1 x LED Test Light
- 1 x 5V Charger
- 1 x USB Charging Cable
- 1 x English Manual (this document)

Image: An illustration showing all components included in the AngelaKerry EF851S package: GPS collar, TPU belt, metal contact points, LED test light, 5V charger, and USB charging cable.
Setup Instructions
Follow these steps to set up your AngelaKerry EF851S system:
- Charge the Receiver: Before first use, fully charge the pet receiver using the provided 5V charger and USB cable. A full charge typically takes 2-4 hours and provides up to 12 hours of continuous working time.

Image: The AngelaKerry EF851S GPS Pet Fence receiver connected to a laptop via a USB cable for charging, illustrating its rechargeable nature.
- Identify a Central Point: Choose a central point in your desired outdoor play area. This point will serve as the center of the circular containment zone for your dog.
- Turn On the System: Take the fence system (receiver) to the chosen central point. Press and hold the power button to turn it on.
- Set the Radius Distance: Use the '+' and '-' buttons on the receiver to set the desired radius of the play area. The radius can be adjusted from 20 meters to 800 meters.
- Position the System: After setting the radius, the device will begin positioning. Ensure the unit remains stationary during this process. The "00" on the screen will flash until positioning is complete. Once "00" stops flashing, the unit has successfully connected with satellite signals and established the boundary.

Image: A visual guide demonstrating the three initial setup steps: turning on the device, adjusting the radius distance using '+' and '-' buttons, and initiating the GPS positioning process.
- Attach to Dog: Once positioning is complete, attach the receiver to your dog's collar. Ensure the contact points are making proper contact with your dog's skin.
Operating Instructions
Once the system is set up and the collar is on your dog, it operates automatically:
- Boundary Detection: The system continuously monitors your dog's position relative to the established circular boundary.
- Correction Sequence: If your dog approaches or crosses the boundary line, the collar will first emit a beep sound as a warning. If the dog continues to move beyond the boundary, it will receive a static correction. This sequence is designed to encourage your dog to return to the safe play area.
- Correction Levels: The system offers five levels of static correction. Adjust the level based on your dog's temperament and response.

Image: A circular diagram detailing the 7 sensitivity levels, indicating how beep warnings are followed by static corrections of varying durations, and the system's sleep mode after repeated corrections.
- Automatic Protection: To prevent over-stimulation, if your dog remains outside the boundary, the stimulation is limited to 20 seconds. It then automatically shuts off for one minute before repeating the stimulation for another two 20-second intervals. In the absence of a stable GPS signal, the system will automatically suspend its correction functions.

Image: A map overlay demonstrating the operational principle of the GPS dog fence, with a central point and a circular boundary indicating the safe play area for the dog.
Important Considerations & Troubleshooting
- Training Period: It is crucial to train your dog for approximately 3 weeks to help them understand how the system operates and to associate the warnings with the boundary.
- Repositioning Required: Due to the nature of GPS positioning, the system requires repositioning every time it is turned on. The central point must be re-established for accurate boundary definition.
- Dog Suitability: Do not use this fence system on aggressive dogs. Avoid using the collar on any dog for more than 12 hours per day.
- Environmental Limitations:
The system relies on strong GPS signals. Therefore, it is not recommended for use in the following conditions or locations:
- Rainy or cloudy days, or areas with dense tree cover, as weak GPS signals can lead to inconsistent boundaries.
- Near tall buildings or inside a house, where GPS signals can be blocked or significantly weakened.

Image: Visual representations of environmental conditions and locations where the GPS dog fence system may not function optimally due to weak or blocked GPS signals.
- Inconsistent Boundary: If the boundary seems inconsistent or your dog receives corrections unexpectedly, check the GPS signal strength. Ensure the device is used in an open outdoor area away from obstructions. Repositioning the device may be necessary.
- No Correction: If the collar is not providing corrections, ensure it is charged, turned on, and has successfully acquired a GPS signal (display shows "00" steady). Verify the contact points are properly touching your dog's skin. Use the LED test light to confirm static correction functionality.
Maintenance
- Charging: Regularly charge the receiver to ensure optimal performance. A full charge provides approximately 12 hours of operation.
- Cleaning: The collar receiver is waterproof. Clean it with a damp cloth as needed. Avoid using harsh chemicals.
- Contact Points: Periodically check the metal contact points for corrosion or damage. Ensure they are securely attached.
- Storage: When not in use for extended periods, store the device in a cool, dry place.
Specifications
| Feature | Detail |
|---|---|
| Model | EF851S |
| Positioning Technology | GPS |
| Adjustable Radius | 20 - 800 meters (22 - 850 yards) |
| Coverage Area | 0.3 - 496 acres |
| Correction Types | Beep, Static Correction (5 levels) |
| Battery | Rechargeable (internal battery) |
| Charging Time | 2-4 hours |
| Working Time | Up to 12 hours (continuous) |
| Waterproof | Yes |
| Suitable Dog Weight | 15 - 120 pounds |
| Parcel Dimensions | 17.6 x 12.2 x 6.1 cm |
| Weight | 350 g |
Warranty and Support
The AngelaKerry EF851S comes with a 1-year warranty. For support in setting up the dog fence, training your dogs, or troubleshooting any issues, please contact AngelaKerry customer care. Refer to the product packaging or official website for specific contact information.
In most cases, if you are not satisfied with the item, you may return it for a full refund within 90 days of receipt of shipment.