Signal Converter

Every signal contains information. Much of this information can be used for warning, control or measurement purposes. In order to be perceived and correctly interpreted, the signals often need to be adapted for the intended purpose and to the receivers. Signal converters are needed to separate, convert or measure technical signals. Those transducers that are used for measurement are also called measuring transducers.

In most cases, the signals recorded by the signal converter are to be converted into a standard analogue or digital signal that can be easily evaluated. In addition, the signals can be filtered or linearized. In industry, the signal converters are used, for example, to monitor machines, materials or processes during the manufacturing. When classifying according to the signal form, a distinction is made between:

• analogue-to-digital converters,
• analogue-to-analogue converters and
• digital-to-analogue converters.

Analogue-to-digital converters or AD converters are signal converters that pass on the analogue input values as digital output values. These signal converters are often installed in digital measuring instruments and measuring devices in order to be able to show the acquired analogue values as numerical values on a display. Analogue-to-analogue converters usually scale or convert analogue input values so that the complete range of values can be passed on via a standard analogue output. Digital-to-analogue converters are signal converters that output the digital input values as analogue values.

Preconfigured or adjustable signal converters
Signal converters can be preconfigured to a specific input variable, such as PT-100 temperature sensors, or used for different sensors and measured variables. The signal converters adjustable by the user can be adapted for different measuring tasks. The adjustment can be made, for example, via DIP switches, via keypads or by means of a PC and programming adapter. Make sure that the type of the setting is suitable for the intended application.

Input and output variables
The electrical voltage, the electrical current and the temperature which is determined, for example, via electrical resistance, belong to the very common input signals for transducers. When using a signal converter for these physical variables, care must be taken to ensure that the measuring range of the converter meets the requirements. However, the signal converters are also used to convert the interface signals output by the measuring instruments into another format. As type for the signal output, for example, analogue standard outputs with 0 ... 20 mA, 4 ... 20 mA, 0 ... 10 V, switching signals, pulses or RS232 or RS485 data can be selected.

Display and keypad
Some signal converters offer a digital display in addition to the signal output. The measured values can also be read out directly on this display. Devices with digital display and control keys on the front panel can be easily and quickly reconfigured at the push of a button.

Mounting requirements
The signal converters that are offered as individual components usually have mounting aids. Many can be mounted directly on C-rails or top-hat rails without the need for screws. The size is usually very compact and is based on the grid for control cabinet installations. For the connection, it is important, when selecting the device, to pay attention to the voltage with which the signal converter can be operated and which conductor cross-sections may be connected. When using the device in a damp or dusty environment, it is important to ensure that it is adequately protected by an additional housing or a suitable IP protection rating.