What to Do If an Electric Fence Is Not Working
By JD Gates Pretoria • Complete Troubleshooting Guide • 8 min read
An electric fence that's not working properly leaves your property vulnerable. Before calling a technician, there are several checks you can perform yourself. This guide walks you through systematic troubleshooting to identify and potentially fix common electric fence problems.
Safety First
Always turn off and disconnect your energizer before making any repairs or touching fence wires directly. While electric fence voltage is high, the amperage is low, painful but not lethal, however, always exercise caution.
Step 1: Check the Power Source
For Mains-Powered Energizers:
- Verify the power outlet is working (test with another device)
- Check if the circuit breaker has tripped on your DB board
- Look for blown fuses on the energizer input circuit
- Ensure the energizer indicator lights are functioning
For Battery/Solar Energizers:
- Test battery voltage, should be 12V+ for most systems
- Check battery terminals for corrosion and clean if necessary
- For solar systems, ensure the panel faces south and is unshaded
Step 2: Test the Energizer Output
Perform an isolation test to determine if the problem is with the energizer or the fence line:
- Turn OFF the energizer
- Disconnect both the fence wire and ground wire from the terminals
- Turn the energizer back ON
- Using a fence voltage tester, measure between the + (fence) and - (ground) terminals
Results:
- Under 5,000V: Energizer or battery is faulty and may need replacement
- Over 5,000V: Energizer is working, problem is on the fence line or grounding system
Step 3: Check the Grounding System
Poor grounding causes 80% of electric fence problems. Your ground system should have:
- At least 3 ground rods, each 6-8 feet long
- Ground rods spaced 10 feet apart
- Ground voltage reading under 300V (test with fence tester touching ground terminal)
- Clean, tight connections with no corrosion
Step 4: Inspect the Fence Line
Walk the entire fence perimeter looking for:
| Problem | Solution |
|---|---|
| Vegetation touching wires | Clear all grass, weeds, and branches |
| Broken or cracked insulators | Replace damaged insulators immediately |
| Wire touching posts or ground | Reposition wire through insulators |
| Broken or rusty wires | Splice or replace damaged sections |
| Corroded connections | Clean and tighten all terminals |
Target Voltage Levels
- Energizer output (isolated): 5,000V+
- End of fence line: 3,000V minimum (4,000-5,000V ideal)
- Ground system: Under 300V
- Critical minimum: Never below 2,000V
When to Call a Professional
- Energizer has been damaged by lightning
- Control board shows signs of burning or damage
- Voltage remains low despite troubleshooting
- You need to add or relocate ground rods
- Wiring needs replacement or major repairs
Need Electric Fence Repairs?
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