5A Range Single-Phase AC Active Output Current Transducer Module

Description

The 5A Range Single-Phase AC Active Output Current Transducer Module is a compact, high-precision current sensing board designed for measuring alternating current (AC) in energy monitoring, load management, and protection applications. Built around the ZMCT103C precision micro current transformer and paired with a high-precision operational amplifier circuit, this module provides an active analog output that is proportional to the primary AC current, making it suitable for direct connection to microcontroller ADC inputs.

At the heart of the module is the ZMCT103C current transformer, a PCB-mount device with a 1000:1 turns ratio. When the primary AC current flows through the conductor passing through the transformer’s center hole, the secondary winding produces a proportional current. At the rated input of 5A, the output is 5mA . The onboard sampling resistor converts this current into a voltage signal, which is then amplified and conditioned by the onboard op-amp circuit for accurate sampling and appropriate compensation .

The module features an adjustable output via an onboard potentiometer. The amplification ratio can be tuned from 0 to 100 times, allowing you to optimize the output voltage range for your specific measurement setup. However, the maximum output voltage (OUT) is capped at 1/2 VCC to ensure compatibility with standard ADC input ranges . The module operates from a wide DC supply voltage of 3V to 35V (some variants specify 5–30V), making it compatible with standard microcontroller power rails .

Important Note: This module outputs an analog AC voltage signal, not a DC voltage. The output waveform corresponds to the primary AC current waveform, with the maximum value not exceeding 1/2 VCC . To read it with a microcontroller ADC, you must either bias the signal to mid-rail (using a voltage divider or op-amp level shifter) or use a bridge rectifier and filter capacitor to convert it to a proportional DC voltage. The transformer provides galvanic isolation (typically rated 3000V–4500V), but proper safety precautions are still required when working with mains AC . The module is not intended for DC current measurement. For precise energy metering applications, calibration against a known reference load is recommended.

Whether you are building a home energy monitor, a solar panel current tracker, or an industrial load monitoring system, the ZMCT103C active output module provides a reliable, isolated solution for AC current sensing with built-in amplification.

Features

• ZMCT103C precision current transformer — 1000:1 turns ratio for accurate AC current sensing

• Onboard high-precision op-amp circuit — Amplifies and conditions the signal for direct ADC input

• Adjustable gain (0–100x) — Potentiometer allows tuning of output voltage range

• Galvanic isolation — Separates high-voltage AC line from low-voltage measurement circuit for safety

• Wide supply voltage — 3V to 35V DC operation (variant dependent)

• Active analog output — Output signal is an AC voltage waveform proportional to primary current

• Compact PCB form factor — Approx. 38 × 18.5mm for easy integration

• High linearity — 0.2% linearity for accurate current-to-voltage conversion

• Wide linear range — 0–10A (with 100Ω load) for measurement headroom beyond the 5A rating

• Wide application range — Energy metering, motor monitoring, overcurrent protection, solar systems

Technical Specifications