What is Current Transducer



Current transducer is a device, which converts current into a proportional industrial standard electrical signal.
Current Transducer Definition
Basically current transducer is formed by four parts, sensitive component, conversion component, conversion circuit, power circuit.
Current Transducer component, sensitive component, conversion component, conversion cirsuit, power circuit

How current transducer works?

The current goes in, usually it is current, voltage, frequency, power, etc. Then the sensitive component will detect the electrical parameter and give a signal.
After that the signal will be passed to conversion component, which can convert the signal to a small current signal. Then it will be passed to conversion circuit, which process the small current signal and provide an industrial standard electrical signal, usually is 0-5V, 4-20mA, RS485.
At the end the output signal goes to terminal equipment, such as display, PLC, alarm unit, automation control, etc.
Current transducer usually has a power circuit, which provide the power to conversion component and conversion circuit.
Current Transducer workflow

Why current transducer is important in many different industry systems?

1. Isolated function.

In the design of current transducer, the input current is absolutely isolated from output current. As in the industry environment, there are a lot of interferences which cause measurement signals to be inaccurate. Using current transducer can get rid of the interferences, so the output signal can fully represent the measured signal.

2. Conversion function.

Current transducer can convert any non-standard electrical current to industrial standard electrical signal, which is much easier for terminal equipment use.

3. Enhance signal for long distance transfer.

Current transducer can enhance week current to easy-received standard signal, so the output signal can be transferred for long distance, such as 4-20mA signal can be transferred up to 1000 meters.

4. Safety function.

When current transducer suffers high voltage or current impact, it will go into protection mode, cut off conversion process, totally isolate between input and output. So that it will keep the safety of terminal equipment, keep the whole system safety.

A power system requires some form of instrumentation to monitor and control its operation. In the past, this function has been performed by electro-mechanical devices. With these devices their use was limited by being confined to close to the point of measurement. Replacing these mechanical devices with their electronic equivalents has allowed the monitoring system to become more versatile. A modern system usually involves the transmission of information from the point of measurement to other points where this data is processed, recorded and used to control the system parameters. The conversion and transmission of physical parameters on the system requires the use of transducers at the points of measurement. These transducers act as the interface between the power system and the measurement system. Current transducers are specifically transducers for converting the raw voltage and currents in a power system into useful and meaningful electrical signals which can be used in and transmitted about the measurement system. The inputs to these devices are usually currents and voltages from instrument transformers such as current transformers (CTs) and voltage transformers (VTs) whilst the outputs are standardised DC currents (0-5V or 4-20mA) or digital signals (RS485).