Technical Specifications
Important: Use only rechargeable lead-acid batteries. Non-rechargeable batteries must NOT be used. The energizer must be installed in a well-ventilated area as lead-acid batteries require venting.
Earth Loop Monitoring Options
No Earth Loop
Bridge the earth OUT to earth RETURN. Functions like the original Wizord energizer without earth monitoring.
Good Soil Earthing
Standard earth loop monitoring for properties with good soil conductivity. Recommended configuration for most installations.
Poor Soil Earthing
Enhanced configuration for rocky or sandy soil with poor conductivity. Uses separate earth wire not coupled to fence earth.
Key Features & Benefits
Programmable Installer Options
Siren-On Time
Configurable from 10 seconds to 4 minutes. Sets how long the siren sounds during an alarm.
Siren-Off Time
Silent period between siren cycles. Configurable from 10 seconds to 4 minutes.
Siren Sound Count
Number of times the siren will sound after an alarm. Options: 1, 2, 3, 6, or 10 times.
Gate Delay Time
Time allowed for gate to remain open before triggering alarm. 15 seconds to 4 minutes.
High Power Fence Voltage
Open circuit voltage when mains is present. Adjustable from 3.0kV to 7.0kV.
Low Power Fence Voltage
Voltage during battery operation. Adjustable from 1500V to 1900V for battery conservation.
Programming requires the 6-digit installer PIN (default: 012345) followed by * 0 # to enter programming mode.
LED Status Indicators
| Condition | Power | On LED | Service | Siren |
|---|---|---|---|---|
| Normal | On | On | Off | Off |
| Power Failure | Off | On | Off | Off |
| Battery Low | Off | On | Pulse (5s) | Off |
| Battery Flat | Off | - | Flash | On |
| Low Voltage | On | Flash | Off | Off |
About Nemtek
Nemtek is a proudly South African manufacturer of electric fence energizers and security products. The Merlin 4 is manufactured by IO Tech Manufacturing (Pty) Ltd and distributed through Nemtek outlets in Randburg and Edenvale.
The Merlin 4 is designed to comply with international safety and environmental standards, making it suitable for residential and commercial electric fence installations across South Africa.
Nemtek Randburg: +27 11 462-8283
Nemtek Edenvale: +27 11 453-1970
What's Inside This Manual
Frequently Asked Questions
What battery does the Merlin 4 use?
The Merlin 4 uses a 12V 7AH rechargeable lead-acid battery. Non-rechargeable batteries must NOT be used. The battery requires venting, so the energizer must be installed in a well-ventilated area.
What is earth loop monitoring?
Earth loop monitoring detects tampering or fence cutting by monitoring the return path through the earth wire. The Merlin 4 offers three options: no monitoring, standard monitoring for good soil earthing, and enhanced monitoring for poor soil conditions.
What voltage does the electric fence produce?
The Merlin 4 produces between 3.0kV and 7.0kV when connected to mains power (default 7kV). During battery operation, it automatically reduces to 1500V-1900V to conserve battery life while maintaining security.
How many keypads can I connect?
You can connect up to 4 keypads or FOB units to one Merlin 4 energizer. Each must have a unique address setting. The keypad cable must not exceed 100 meters in total length.
What happens during a power failure?
The Merlin 4 continues operating on its 12V 7AH battery during power outages. It automatically reduces fence voltage to conserve battery life and uses a unique algorithm to extend operation time.
How do I reset the energizer to factory defaults?
Disconnect mains and one battery terminal. Reconnect the battery and apply mains. Within 38 seconds, enter 2 3 8 9 # on the keypad. The energizer will turn off to confirm defaults were loaded.
What causes the service light to flash?
The service light flashes for 5 conditions: communications failure (if keypad detect is enabled), fence interference, over temperature, energizer fault, or flat battery. Open the lid to see diagnostic LEDs.
Does the electric fence use a lot of electricity?
No, the Merlin 4 is very energy efficient. Typically consuming only 10 Watts, 100 hours of usage costs approximately one unit of electricity, making it economical to operate.