Digital Panel Meters
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Useful information about digital installation measuring devices
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What was digital panel-mounted measuring devices?
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The versatile application possibilities of digital installation measuring devices
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What digital panel-mounted measuring devices does Conrad offer?
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FAQ – Frequently Asked Questions about Digital Mounting Meters
What was digital panel-mounted measuring devices?
Digital panel-mounted measuring devices are electrical test devices for detecting certain electrical parameters . The values determined are displayed as digital numbers or as graphics, depending on which display format is best suited for the respective measured variable. In this category you will also find products that use high-resolution graphics to simulate the pointer of analogueue measuring instruments.
With the help of complex converters, digital panel-mounted measuring instruments convert the electrical quantities to be determined into usable measurement results. Individual values, measurement series and continuous measurement sequences can be recorded (saved) over different time periods. Digital measuring instruments are often programd for measuring and testing tasks, so that they can be measured independantly of human activities. Most devices are equipped with backup batteries to store the programd operating state of the measuring device independantly of external power sources. Programming of the measuring instruments is possible on several ways : on the one hand external programming sources are applicable via interfaces, on the other hand the measuring instruments are equipped with DIP switches or jumpers for programming, which is described in detail in the respective operating instructions. There are also digital measuring devices with menu-driven setting and operation with plain text display on the display.
The versatile application possibilities of digital installation measuring devices
The digital panel-mounted measuring devices available from Conrad can be used to record numerous parameters and for different purposes, depending on the model:
- Voltage
- Current
- Neutral current
- Apparent, active and reactive power
- Power factor
- Frequency
- Minimum/maximum values with date and time (time stamp)
- Non-linear distortion factor
- Distortion current strength
- Phase angle
- Harmonics
- For recording the consumption of a part or production process
- As operating hours counter or limit value monitoring with event recording
When programd, measurement results can be classified as information, warning or alarm. By means of extensions with digital or analogue modules , processes monitored by these measuring devices can be triggered, controlled or stopped.
For connecting digital panel-mounted measuring devices to the components to be monitored, certain cables with twists and screens are recommended, which you can also buy from Conrad, for example data cables or network cables.
The measuring instruments are usually installed in control panels with the common installation dimensions 144 x 144, 96 x 96 or 68 x 68 millimeters. Rectangular designs are also available.
Many of the devices available from Conrad are suitable for use in industrial environments , often the visible front has a guaranteed protection class (up to IP 65: Dust-proof, complete touch protection and protection against all-sided splash water).
What digital panel-mounted measuring devices does Conrad offer?
The measuring instruments can be selected in the Conrad online shop according to price segment, new products and offers (with RoHS), customer evaluation, branch availability and manufacturers.
In technical terms, a distinction is made between the available interfaces on the respective measuring instrument. A part of the devices has several interfaces :
Ethernet/LAN
Connection to networks for programming the measuring instrument and/or for evaluating the measurement results either via LAN connections or other forms of network cables
RS 232 Modbus RTU
Industrial bus architecture for master-slave communication with connected components via a cable with a limited cable length
RS 485 Modbus RTU
Like RS 232 Modbus RTU, but with up to 32 subscribers and large cable lengths
RS 232
Recommended Standard 232 from the early 1960er for serial interfaces to computers
RS 485
Industry interface standard for asynchronous serial data transmission with better electromagnetic compatibility
USB
Universal Serial Bus, which was to replace all existing serial interfaces from 1996
PROFIBUS DP
Master-slave data exchange via a fast serial connection with distributed devices via a defined system architecture
No interface
Simple measuring devices with their own battery, which are connected directly to the measuring point
Optional interface
Measuring instruments with the option of retrofitting with interfaces
Manuals, some of which are multilingual, are available for download for the products on offer.
FAQ – Frequently Asked Questions about Digital Mounting Meters
Where are digital panel-mounted measuring devices used?
Mainly in the professional industrial sector for monitoring complex processes and in the domestic installation. Simpler devices are suitable for testing, troubleshooting, analysis and repair in the home and hobby area.
- The handling of these devices requires special knowledge by suitably qualified personnel.
- Take the devices out of the transport packaging with care and only with suitable tools and carry out a visual inspection for damage.
- Check the package contents for completeness before starting the installation.
- Only operate digital installation measuring devices according to the information in the operating instructions and, if necessary, observe the legal and safety regulations required for the respective application. There may be country-specific deviations.
- When laying signal and control cables, observe the rules of electromagnetic compatibility: Mains cables, motor supply cables, supply cables of rectifiers and the like do not belong in the vicinity of measuring and control cables. These lines should be routed in conductive, grounded cable ducts. This is especially true for long cable runs. Control panels should always be grounded.
- Lay signal cables within control cabinets as far away as possible from protecting, control relays, transformers and other sources of interference.
- To clean the display, you should use soft cloths with a mild detergent and not aggressive cleaning agents.
- In the event of any visible damage or malfunction, immediately discontinue use.
- Before opening a device, inform yourself about the warranty conditions and disconnect the power supply.
- Digital panel-mounted measuring devices can be recycled as electronic waste in accordance with the legal regulations.
How do errors in digital panel-mounted measuring devices become apparent?
- No indication on the display due to a defective measuring device, missing supply voltage or missing measurement results from the measuring point
- Poorly readable display due to incorrectly set contrast regulator
- For programmable measuring devices, the date can jump to 1.1.1970, the start of the so-called UNIX time. In this case, the backup battery is usually exhausted.
- Output of a sequence of the letter "E" in the display indicates an error ("Error"), which is usually provided with additional information, for example "V" for "faulty voltage measurement".
- Digital measuring devices can become unusable due to prolonged storage under unfavorable conditions (outside the permissible climatic limits, humidity, condensation) or during transport.