Registration technology
The registration technology consists of data recording devices for industrial use for measurement data acquisition / logging. Other terms that depend on the recording method used are paper recorders , paperless recorders or screen recorders .
operation area
The recording of measurement data in industrial processes begins very early with the aim of controlling or regulating the running processes, ensuring and reproducing quality, optimizing processes and reducing the use of materials. Current or voltage signals that are supplied by the corresponding measuring sensors are recorded.
The measurement parameters that are still most common today are temperature , pressure , flow rate , level , pH , conductivity , and others, i.e. properties of the medium to be monitored, but also current , voltage , power , etc. from the field of energy generation are often measured and recorded. It is only in the last few decades that measurement parameters such as vibrations , acceleration , magnetic fields , etc., which are mostly related to the devices used in the manufacturing process such as e.g. B. Engines employ to record. The aim is to plan and initiate maintenance or repair work in good time before a device is damaged or fails.
Recording technology devices (process recorder)
In principle, a distinction is made today between two device variants. On the one hand there is the category of "paper recorders" which use paper as a recording method, on the other hand the "paperless recorder" where the measurement data is displayed on a screen and simultaneously saved on internal or external media.
When paper Schreiber the paper (mm / h, typically 20) "drawn past" at a set feed rate of write units. This creates the writing strip with the recorded measuring lines. Depending on the type of device used, pre-printed, partially printed or white paper is recorded. There are also recording technology devices that work with time offset compensation, so that all recorded measured values correspond to the same time base.
When paperless recorder measurement lines / values constantly updated on the screen. Recently, SD cards (typically in digital cameras) and USB sticks have been used as storage media. However, floppy disk drives , hard drives, permanent storage and flash cards are still used . In addition, there are recording technology devices that offer both options, i.e. paperless recorders with paper recording or paper recorders with measurement data storage.
List of recording technology devices still used today
(All device types listed below relate to an installation variant of 144 × 144 mm switch panel cutout.)
Hang-up writer
The recording method is derived from the name. A bracket is moved over the paper and when the measured value is reached, it falls onto a ribbon and prints a point on the paper. This process is repeated at regular time intervals with simultaneous forward movement of the paper, so that it becomes a measuring line on the paper.
Advantages: The device structure is simple, there are few mechanically moving parts and can therefore be manufactured inexpensively.
Disadvantages: Not suitable for rapidly changing signals, as up to a minute can pass between the individual recording points.
(Color) line writer
With the line recorder, up to four writing units are staggered one above the other. Each writing unit has its own color cartridge / ink tank with it. Typical colors are blue, red, green and purple.
Advantages: By using separate writing units, the measurement signals are continuously scanned. Signal changes within 0.5s can typically be processed.
Disadvantages: Many mechanical components from the writing units to the paper transport. Ink tanks have to be replaced regularly, otherwise the measured value recording will be lost.
Variants: A variant that is frequently used is the "alphanumeric or hybrid writer". A printer unit that prints alphanumeric characters is installed in addition to the writing units (lines). Thus z. B. time, measurement channel designations, limit violations, etc. can be printed directly on the paper.
(Color) dot printer / writer
The point printer / writer differs from the line writer only in that instead of several line writing units, a single point printing unit with up to 6 colors is used.
Advantages: More measuring channels can be recorded. Fewer mechanical components compared to the line recorder.
Disadvantages: The measurement signal is not read in continuously because it switches between the input signals. Ink tanks have to be replaced regularly, otherwise the measured value recording will be lost.
Variants: A variant that is frequently used is the "alphanumeric or hybrid writer". The dot printing unit is used to print alphanumeric characters. Thus z. B. time, measurement channel designations, limit violations, etc. can be printed directly on the paper.
Thermal paper printer / writer
Here, too, the recording method is derived from the device name. So-called thermal paper (heat-sensitive paper) is used instead of conventional paper. A “thermal comb” is often used as a “pen”, which is heated at a certain point and thus leaves a (mostly black) point on the paper according to the measured value. Here, too, the image of a measuring line is created by the simultaneous paper transport.
Advantages: Modern devices achieve a very high recording speed of up to 100 ms
Disadvantages: Complicated device structure, expensive electronic and mechanical components, temperature-sensitive paper (loses the recording if stored improperly), recording only in black and white
Variants: The predecessor of the thermal paper writer is the metal paper writer (no longer in use), a needle was moved over the paper and a current discharge (spark) was triggered. The metal paper was colored black by the current discharge. A hybrid pen with thermal paper and simultaneous color line recording is still in use today. The advantages of the thermal paper recorder are used and the disadvantages of black and white recording are compensated for with a color line unit.
Paperless recorder
In the case of the screen recorder, paperless recorder or display recorder, no mechanical components are used, apart from data storage devices such as floppy disk drives or hard drives, and are a special type of data logger . The measured value is displayed on a screen in line format, as a digital value, as plain text information up to the free setting option. The data is recorded in the paperless recorder itself and is read out at regular intervals. The measurement data is evaluated and saved on a PC with the associated software. Videographic recorders are the most widely used recording technology devices today, as they offer the greatest benefit and flexibility at the same time.
Advantages: No mechanical components, free setting options up to free programming, monitoring of many measurement signal inputs, standardized storage media, simple archiving of the data (several cabinets of paper rolls fit on one DVD), certified software, low maintenance costs, recording interval is mostly due to alarms (limit value exceeded, digital inputs etc.) customizable
Disadvantages: A PC is required for data archiving and data evaluation.
Typical manufacturers of "recording technology devices"
Since the 1990s there has been a major shake-up in the market , so that today there are only a few providers of paper and paperless recorders. This is especially true for the hardware, some of which is sold by several companies:
- Endress + Hauser Messtechnik GmbH
- Sitrans R or Sirec D display recorder from Siemens AG
- Camille Bauer and Gossen Metrawatt
- Temptron data loggers
- For all other manufacturers or devices for video recorders, see the market overview of the SPS magazine
Individual evidence
- ↑ Siemens - Automation Technology - Display Recorder ( Memento of the original from October 26, 2010 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Camille Bauer - overview of process management
- ↑ Temptron - measurement data acquisition
- ↑ SPS-MAGAZIN: Product catalog screen data recorder (1 + 2/2012) ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.
