indoor air and environmental monitoring

 
electronic systems - data loggers
Data loggers are devices that are used both at environmental and at industrial applications. Such data collectors can be operated stationary (net operation) or mobile. The different variants offer numerous possibilities for recording and evaluation. It is possible to store the data on the device (offline-mode) or to visualise them directly on an operating PC via the suitable software (online-mode).

At environmental applications data loggers are frequently used outdoor; whereas at industrial applications predominantly indoor. For this, data collectors must be configured for net-dependent as well as for a mobile, net-independent use. For each data collection task in industry and environment the following 4 central questions have tob e asked:
 

• Which sensors do you wish to integrate? Which expectations concerning the sensors do you have referring to accuracy and long-termed stability?
• How shall the data logging system be equipped, unflexible (fix number of channels) or flexible (extendible)? How shall the system be supplied, net-operating or by means of solar power? How long shall the system run (5 years or rather 15 years)?
• How shall the data be read out (via TCP/IP, ethernet, GSM, GPRS, UMTS, other remote methods, phone net, etc.)? Shall the system be read out online (real-time) or cyclic (offline)? How often do you wish to read out? Do you wish to integrate an on-site memory for a higher data security at online systems? How reliable shall the registration work? Is a "risk-sharing-architecture" important in order to share the risk of data loss to various system modules? Are alarmings or on-site displays requested?
• Which requirements do you have concerning the software? Is an interface requested for further processing of data (file or data bank, tamper-proof data or editible data, flexible data retrieval to optimise costs)? Are there special wishes (system specifications requested)?

mechanical systems – pen recorders
Pen recorders are used for continuous logging of physical variables. In addition to their use for weather observation and weather forecast certain working processes are also possible application fields, provided that the climatic conditions are important e.g. in computer rooms or in graphical business. For controls on the storage of products these devices have been well proved. Theis use in the horticultural business is also appropriate.

Further application fields are the natural scientific research, laboratories, university institutes, museums, etc.

The climatic measuring variables (pressure, temperature and humidity) are transferred from the measuring element via a level mechanism and the the writing arm to the diagram fixed at the reel of the clock work. The registration is carried out automatically. By means oft he registration curves the history of the measuring values can be seen any time. Registration is done by means of quartz-controlled, electronical writing reel gear onto diagrams with different periods.

All devices are ready for operating at dispatch. Without any larger preparations they can immediately be used by the receiver. The built-in measuring harp of the construction types with internal measuring element can be unhooked and moistend with distilled water to regenerate the hygrograph. Hygrographs with external measuring elements that are installed in protective cages can be checked and regenerated by pulling over a moistened cloth cover. The external dimensions of both of the construction types are different.