This 12V DC Overcurrent Protection Sensor Module is a precision safety device designed to monitor AC current and protect your equipment from electrical overloads. It utilizes an onboard current transformer to detect the magnetic field of an AC line, converting it into a measurable signal. When the current exceeds your user-defined threshold, the integrated relay triggers instantly, allowing you to cut power to the load, sound an alarm, or signal a PLC.
This module is an essential fail-safe for industrial motors, household appliances, and DIY automation projects. By providing a hardware-level cutoff, it prevents overheating, fire hazards, and expensive hardware damage caused by mechanical jams or electrical shorts.
Key Features
- Precision AC Detection: Monitors AC currents from 0A to 5A with high sensitivity and accuracy.
- Adjustable Threshold: Features a multi-turn potentiometer for fine-tuning the exact “trip point” where the relay activates.
- Isolated Protection: The current transformer provides physical isolation between the high-voltage AC line and your low-voltage DC control circuit, ensuring maximum safety.
- Switching Relay Output: Equipped with a high-quality relay (typically 10A capacity) that acts as a dry-contact switch for controlling external loads or sirens.
- Visual Status Indicators: Onboard LEDs provide immediate feedback on power status and relay activation.
- Compact Mounting: Industrial-grade PCB with pre-drilled holes for easy installation into control panels or project boxes
Q: Can I use this to monitor DC current?
No. This module uses a current transformer, which relies on electromagnetic induction. It is specifically designed for AC current detection only.
Q: Why do I only pass one wire through the transformer hole?
If you pass both the Live and Neutral wires through the hole, their magnetic fields will cancel each other out, and the sensor will read zero. You must isolate a single wire to detect the current flow accurately.
Q: Is the 5A limit the maximum the relay can handle or the maximum it can sense?
5A is the maximum sensing range of the transformer. The relay itself can typically switch a load up to 10A. If your AC line routinely carries more than 5A, you would require a module with a larger transformer.
Q: Can this module be used for "Undercurrent" detection?
While primarily used for overcurrent, you can use the NO (Normally Open) contact to trigger an alert if a machine stops drawing current (indicating a belt break or motor failure).
Q: Is this suitable for commercial motor protection?
Yes. Business purchasers frequently use this module for protecting small industrial motors, pumps, and fans where a mechanical jam could cause the motor to burn out. It provides a much faster response time than a standard thermal fuse.
Q: Does the module reset automatically?
Yes. Once the AC current drops back below the set threshold, the relay will release and return to its original state. If you require a “Latch” (where the power stays off until manually reset), you will need to add a simple external latching circuit or use a microcontroller.
