The single-phase current transmitter is an electrical power testing substation developed based on research in motor testing and measurement technology, and in accordance with IEC and relevant national standards for motor testing, specifically for single-phase AC power measurement in motor testing. It employs advanced filtering technology and a reasonable software algorithm to solve the problems of low measurement accuracy and unstable measurement data found in general-purpose instruments. The single-phase current and power transmitter features low power consumption, high accuracy, and light weight. Its customized design digitizes the measured front end, outputs digital signals, and transmits them via a serial fiber optic bus. Centralized management through a distributed measurement and control master station, it possesses excellent voltage isolation and electromagnetic compatibility, and strong anti-interference capabilities. It is suitable for front-end electrical power acquisition in distributed measurement and control systems.
The characteristics of a single-phase current transmitter are:
1. High accuracy (typically 0.2%, best 0.05%);
2. It exhibits extremely high linearity across the entire measurement range;
3. High degree of integration, simple structure, excellent temperature characteristics and long-term working stability, which eliminates the need for periodic calibration of the transmitter.
A single-phase current transmitter converts the measured signal into a voltage, which is then directly converted into a voltage with excellent linearity and complete isolation from the measured signal by an HCNR200/201 linear optocoupler. This voltage is then sent to the output via a constant voltage (current) converter. It boasts advantages such as a very simple operating principle, refined circuit design, high reliability, and convenient installation.
A single-phase current transmitter can directly convert the AC current in the measured main circuit into a DC 4-20mA constant current loop standard signal (converted to DC 1-5V through a 250Ω resistor or DC 2-10V through a 500Ω resistor) output in a linear ratio, and continuously transmit it to the receiving device (computer or display instrument).
Single-phase current transmitters have highly insulated primary and secondary sides and are available in two-wire and three-wire output wiring configurations. Three-wire transmitters have a positive terminal, a negative terminal, and a signal output terminal for an auxiliary power supply of +24V.
Single-phase current transmitters feature high accuracy, small size, low power consumption, wide frequency response, and strong anti-interference capabilities. The two-wire ports offer strong protection against induced lightning strikes and surge currents. They are particularly suitable for intelligent monitoring systems of load currents from generators, motors, intelligent low-voltage distribution cabinets, air conditioners, fans, streetlights, and other similar devices.
The single-phase current transmitter has ultra-low power consumption, with a static power consumption of 0.096W, a full-scale power consumption of 0.48W, and an internal power consumption limit of 0.6W for the output current.
