Monitoring the environment
The Humigraf measures the temperature and the humidity of the air around it. From this, the dew point can be calculated. The stylus presses against the waxed paper roll, leaving a permanent record of Relative Humidity, Temperature or Dew point. The record is immediately visible in the display as a clear, continuous trace – produced on a rectilinear axis without the use of ink or pens. (Note – to guarantee perfect recording, ensure that the apparatus, and in particular the stylus, is not contaminated with sand, dust or dirt and is not blocked by ice.)
Because the stylus acts on the reverse side of the paper roll, this is as easy to load in the instrument as a roll of film in a camera.
Modern concept
It is the application of modern technology (microprocessors, surface-mounted components) that gives the Humigraf an advantage over both mechanical (conventional Hygrograph, Thermograph) und purely electronic (Data logger) devices. This combined with minimum physical dimensions and weight and maximum precision. Ease of operation and excellent readability are naturally to be expected, along with attractive practical features such as Alarm and display of Minimum and und Maximum values.
Maximum accuracy
A microcomputer controls all the functions of the Humigraf. The analogue sensor signals are amplified and digitalised in the Signal Processor and then input to the Microcomputer, which then calculates relative humidity and temperature. The compensation algorithm applied to the sensor guarantees an extremely high accuracy throughout the full operating (i.e. temperature) range. The application of modern electronics (no need for trim potentiometers!) ensures the long-term stability of the Humigraf.
Quartz precision
The paper feeder is controlled using a quartz precision servo motor. A second servo controls the movement of the stylus via a spindle
Digital display
In addition to the primary display (i.e. the paper roll) the Humigraf has a secondary LCD display, capable of showing Temperature and Relative Humidity, Dew point, or Data required during set-up of the instrument.
Here, for example, the display shows 12.5°C, 74%
Minimum and Maximum Values
Can be shown on the digital display at the touch of a button.
Alarm
An acoustic and visual alarm indicates that the limit levels set by the user (temperature and relative humidity) have been exceeded.
Self-contained
To conserve power, the microcomputer automatically switches to standby mode between readings. Only the LCD display, and other basic functions, operate continuously. Power consumption is so small that the Humigraf can run on a single standard battery for a whole year. It needs no mains connection.
Further details
Battery voltage is regularly measured and shown on the LCD display. The battery can be changed without using tools. Battery life exceeds one year.
To guarantee optimum reliability, gold-plated contacts are used throughout the Humigraf. The battery connections use multiple contacts to ensure no open circuits.
A special waxed paper is used for recording – one roll is sufficient for a whole year. The paper record will not degrade even after many years' storage and can therefore be used as formal evidence in, for example, legal liability or insurance assessment cases. (This is of course not possible with conventional electronic data logger data, as this can easily by manipulated by PC.)
PC-Interface
Humidity and temperature data from the last 20 days is stored in a buffer memory. Data resolution is 0.1°C / 1%. Using the adapter cable supplied, this data may be loaded onto any PC for recording or processing. The system software is compatible with Windows from 95, to 07. Using Excel, graphical display of the data recorded can be automatically generated – we have developed a Macro for this application, which we can be supply as an option.)
The use of open software enables the user to manipulate the data recorded as he or she requires.
Applications
Museums, Galleries, Libraries, Warehouses, Meteorology. The paper, printing, textile, musical instrument or tobacco processing industries,Wine cellars, the storage of antique furniture, etc.
Swiss Quality
The Humigraf is a true European product - over 90% of all components are manufactured in Europe. The instrument itself is assembled and tested only in Switzerland. A Swiss Precision Instrument!
