CURRENT MEASUREMENT IN LARGE AREA: In my research on the forum’s request, I came across an intriguing circuit. Although I haven’t personally tested it, I’m sharing it with the belief that it has the potential to work effectively. I plan to experiment with this circuit in the future and will gladly share the results with you. I’m always available to assist friends who decide to try out this circuit, and I wish you success in your endeavors.
Now, let’s take a brief overview of our circuit and attempt to explain its operational principles. When examining the datasheet of the Hall effect element UGN3503, we find that it operates in an analog manner. In other words, it converts the magnetic current amplitude into a voltage signal. Doesn’t this principle sound similar to that used in pen ammeters?
The UGN3503 takes on the role of the bobbin in this application, offering a sensitivity of 1mV per 1 Ampere. Trm1, one of the trimpots in the circuit, is adjusted for this specific purpose, while Trm2 serves as the reset adjustment. To achieve this setup, Pot1 is positioned in the middle, and the instrument is connected to the DMM (Digital Multimeter) circuit. The DC 200mV range is selected. While the measuring head is in an idle state, it should read 00.0mV on the DMM scale. If your multimeter has an automatic range, please ensure to manually select the 200mV range.
UGN3503 Ratiometric Linear Hall Effect Sensor:
Making the measurement head:
The measuring system of both pencil meters incorporates a mechanism for measuring the current flowing through the conductor under examination. This system functions consistently in multi-phase measurements as well.
One of these pencil meters determines the current by measuring the voltage induced in a coil wound around the conductor and displays it in amperes. UGN3503 is situated at the outer end, which is more suitable for the range corresponding to these pencil meters. It is connected to the electronic unit via a shielded cable using an appropriate connector.
Calibration:
Another ammeter is utilized to gauge the current draw of an electrical device. Before conducting the measurement, the measurement unit is reset. A conductor representing the specified load is inserted between the measurement unit’s terminals. Trm1 is adjusted to ensure that 1mV corresponds to 1 ampere. If the current to be measured is direct current (DC), the DMM (Digital Multimeter) should be set to the DC200mV range. On the other hand, if the load is alternating current (AC), the DMM should be configured to the AC 200mV range. It’s important to note that while this circuit has not been physically tested, it is expected to operate in principle. For instance, if the load current is 10 amperes, it should register as 10 millivolts.
Achievements to friends who will try.
SCHEMATIC CIRCUIT DIAGRAM:
