The ALMEMO® system
The ALMEMO® system comprises an ALMEMO® measuring instrument and intelligent ALMEMO® connectors for the relevant sensor equipment. An extensive range of measuring instrument variants is thus available - from the single channel transmitter right through to data acquisition systems with over 1000 measuring points. The only differences between most of the measuring instruments in the ALMEMO® series concern their housing (i.e. handheld instruments, desktop instruments, 19-inch systems, fitted panel instruments, transmitters, etc.), the number of measuring inputs (1 to 250), the display, output, and operating controls, and their respective power supplies. As soon as a sensor or interface cable is connected, the ALMEMO® measuring instrument will, thanks to the intelligent ALMEMO® connector system, be completely programmed right through to process scheduling. These measuring instruments provide a uniform range of functions with many configurable options. All parameters can be accessed via the interface and can, since the media in the connectors are always overwritten, be freely modified as and whenever necessary.
»Only one measuring instrument for all sensors !«
An extensive range of transducers, sensors, and signals can be connected to any measuring input on virtually any ALMEMO® measuring instrument - all via the patented ALMEMO® plug system Since all the sensor data is saved in the connector, no extra programming is required; as soon as a sensor is connected, the measuring instrument is configured automatically. The sensor data memory (EEPROM) ensures that each sensor can be identified, scaled, and calibrated - all on the basis of its own unique designation. This system of individual sensor designations avoids confusion and makes the measuring setup clear and logical. Sensor errors can be corrected within the plug, turning simple sensors into precision transducers.
Standard signals can be displayed in their original dimensions. For multi-purpose sensors (e.g. temperature and humidity) only one shared plug will usually be required. Programming can be protected by a graduated locking function.
New ! for digital sensors see ALMEMO® digital connectors
What happens with your own sensors ?
With ALMEMO® measuring instruments you will not need new sensors. For your existing sensors we will provide you with a matching adapter that you can fit quickly and easily. You can also program ALMEMO® plugs yourself quickly and easily via keypad, terminal, or software. The data medium in the plug can be overwritten as and whenever necessary.
ALMEMO® measuring instruments are ideal for all sorts of application. All incorporate the same measuring input circuitry. For applications that are not sector-specific there are more than 60 standard measuring ranges available, e.g. for measuring :
Temperature, humidity, flow velocity, flow rate, heat flow, pressure, rotational speed, frequency, resistance, current, voltage, force, strain factor, displacement, pH value, redox potential, conductivity, O2, CO2, CO, O3, etc. Maximum and minimum values are saved automatically. Measured values can be averaged over a series of individual measurements, over the output cycle, or over the actual measuring duration; limit values can be monitored in terms of programmable maximum / minimum values. Measured values can be corrected with regard to zero point and gain and can be scaled by factor, base value, exponent, and units.
ALMEMO® measuring instruments are real individuals. ALMEMO® instruments automatically recognize the specifications of a sensor as it is connected. Specific functions will only be activated as and when the appropriate connector, interface cable, or module is detected. With humidity sensors the dew point, mixture ratio, vapor pressure, and enthalpy will be calculated automatically. Measuring operations involving psychrometers, dynamic pressure probes, or probes for solute oxygen may require pressure compensation; for this purpose the prevailing atmospheric pressure can be entered manually or calculated automatically by an integrated pressure transducer. When measuring dynamic pressure, pH value, atmospheric humidity, solute oxygen, or conductivity it is possible similarly to perform temperature compensation. When using flow sensors to measure volume flow the appropriate cross-section can be entered. For certain special sensors there are connectors available incorporating an integrated adapter circuitry.
most stringent requirements
ALMEMO® measuring instruments meet even the most stringent requirements. ALMEMO® devices incorporate a high-resolution 16-bit A/D converter, digital linearization (for Pt100 sensors with the new ITS 90 temperature scale), and digital calibration. Optimal cold junction compensation is ensured by means of precision thermistors incorporated in the socket spring. Measuring inputs, power supply, and interfaces are all electrically isolated from each other.
The ALMEMO® data acquisition system adapts to your requirements. The internal measured data memory incorporated in ALMEMO® data loggers can be expanded by adding external capacity and can be configured either as linear or ring memory. This memory can be read out selectively according to time or number. The switchover between measuring points is electrically isolated using semiconductor relays that are totally wear-resistant. Continuous measuring point scanning at 10 or 50 measuring operations per second can thus be performed trouble-free. Measuring point scans can be individually programmed. Measuring cycles and output cycles can be selected independently; measured values, average values, and maximum / minimum values can be selectively output and / or saved to memory. The start / stop of each measuring point scan can be variably controlled (by keypad or interface, by date and time-of-day, by limit values, or by an external signal). All measuring instruments can be addressed via interface and are thus fully network-capable. Up to 100 devices can be networked either via cable or over a wireless link. The output of measured values from all devices in the whole network can be initiated from any one such device. For covering longer distances RS422 drivers and distributors are available. This system minimizes hardware requirements, cabling costs, and possible EMC problems, and can be expanded as and when required.
accept virtually any peripheral equipment
ALMEMO® measuring instruments accept virtually any peripheral equipment. while maintaining optimal data transmission. Analog or digital interfaces are not integrated in the measuring instruments themselves but in the connectors and connecting cables. Depending on requirements a wide variety of adapters can be connected, e.g. analog outputs, various interfaces (RS232, RS422, optic fiber, current loop, Ethernet, Bluetooth), alarm signaling devices, or trigger inputs. Data can also be transmitted via a standard fixed-line telephone (analog or ISDN) or a wireless modem at a maximum baud rate of 9600 baud for remote interrogation purposes.
provide evaluation of measured data easily and conveniently
ALMEMO® measuring instruments provide evaluation of measured data easily and conveniently. Suitable output formats are provided for printers or spreadsheet software. For the graphical presentation and the evaluation of measured data there are various software packages available.
can be programmed quickly and easily
ALMEMO® instruments can be programmed quickly and easily. The software protocol and the commands list are identical for all devices. Only one terminal is enough to program all parameters and to scan the measured data. There is a free WINDOWS configuration software, AMR-Control, with terminal, available for this purpose.