Hydrometeorological Instruments and Facilities

Kiefernring 47,
D-14478 Potsdam

Company Profile

H.I.M. is a specialist provider in the field of meteorology, hydrology and aerology.
It offers sales, maintenance and service of high-quality meteorological and hydrological measuring instruments. The products are designed for professional use, but are also suitable for the interested layman.
The product portfolio of H.I.M. consists of 6 columns:
1. distribution of complete meteorological stations or parts of them. Here, quotations and complete projects are prepared and implemented on customer request, and all maintenance is carried out on customer request.
2. production of OEM products The company H.I.M. manufactures parts of conventional meteorological instruments.
3. production and exclusive distribution of an own industrial PC line for digital sensors Software http://www.himcomp.net..
4. OEM distribution of software including MDO software and energy data software in the new German states.
5. exclusive distribution of fine dust measuring technology of a German and Italian manufacturer.
6. exclusive distribution of wind sock stations for airports and helipads.





Windsock station HIM 120 MB according to FAA / ICAO standard with illumination

Windsock station HIM 120 MB according to FAA / ICAO standard with illumination for estimation of wind speed and wind direction, with illumination.
Consisting of:
- Wind bag cover max. Ø 100 cm , L: 600 cm, standard 90 x370 cm
- Mast Ø 120 mm, red/white powder-coated,
- Foundation plate for wind bag station
- Mast foot,
- Steel basket with extender, and fixing material
- Bracket cable winch for aluminium mast (optional)
- Aluminium mast Ø 120 mm / 6000 mm, wall thickness 3mm
- rotating basket 90 cm for windsock station
- 4 halogen rings for light cross of the windsock station
- Obstruction light for the light crown of the windsock station
- 10 meter cable+box for light crown of the windsock station
- Wind bag cover for wind bag station
NATO certified wind sock station.

Other stations on request.

Windshield acc. to Tretjakov

The wind shiels  according Tretyakov is equipped with vertically arranged in a circle metal slats. The metal blades are movable horizontally and combined tapered at the base of the rain gauge. The individual slats are interconnected by a chain, which has the very good aerodynamic properties.

The draft shield according Tretyakov composed of:

· Standpipe for the rain gauge
· frame
· Metal slats
· Small parts for assembly

Measuring height

The windshield after Tretyakov is for measuring heights:

100 cm
150 cm and
200 cm offered.

To install the existing foundations and screws are used in the measurement field.

The windscreen is made of V2A 1475 The life of 10 years can not be guaranteed when used under average meteorological conditions. For use on islands this guarantee can not be given.


2.1. The ring

The windshield after Tretyakov consists of 24, 35 cm long, circularly arranged metal fins. The metal strips are trapezoidal and have a U shape. The windshield is adjustable in height.

The arrangement on the circle having a diameter of 1060 mm is carried out at the same distance by means of slots. This also enables easy replacement of the metal blade is guaranteed.

The slats are arranged vertically movable. This allows a pendulum motion of the slats depending on the inflow direction and the wind speed with the aim to reduce the turbulence occurring at the rain gauge and thus to increase the collection efficiency.

Structurally there is provided a swivel range of 30 °.


In the aerodynamic shape of the upper ends of the metal plate was made, as this leads to deposits of snow. The deposition of hard rainfall leads to delayed rainfall measurement when the precipitation is entered by wind in the encoder.

The modified in this way wind shields are used in the offered version for years successfully in precipitation measurement network of CHMI.

The metal strips have been connected at the lower end with a rope V2a. The plastic parts shown are replaced by V2A components.

The cable limits the pendulum movement and increases the rigidity of the system, whereby the metal fins remain at higher wind speeds at the ring and the effectiveness of the overall system .4 increased.


To facilitate the maintenance of the rain gauge is an element of the ring is designed foldable. The element is secured with thumbscrews and can be removed without tools.

5.The Frame

The supports are placed offset in 120º and are tapered at the foundation base. The supports are fixed using the existing foundation on pins.

The supports and all the connecting components are made of V2A. The whole is also height-adjustable on the supports. This allows the system to be re-leveled and the requirements of the measuring point to be adjusted.


The windshield can be retrofitted with a holder for an anemometer for correcting the precipitation values.

Psychrometer table according Assmann

All Products are avalable as CD,USB Hardcover and Paperback version.
Product information "Psychrometer table according Assamnn Volume 1 CD, Tables about Saturation Vapour Pressure on Ice and Water- Psychrometer Tables on Ice and Water for artificially ventilated Assmann Psycrometer"

In this edition of the psychrometric table the current changes of the psychrometric constant have been considered. The basis for the calculation is the psychrometer formula according to Dr. Sonntag as well as the psychrometer formula recommended by the WMO (CIMO Guide No.8, Issue 1128 pp., 2014, update 2017). This aspiration psychrometer table allows the determination of the saturation vapor pressure over ice and water in a temperature range of max. -60 °C to +60 °C and the rel. Humidity in the measuring range from 1-100 % r. F. The assumption is always the knowledge of the psychometric difference and the dry temperature which is readable in 0.1-K-steps in the tables. All calculated measures refer to the international standard atmosphere (ISA). The atmospheric pressure is 1013.25 hPa. Corrections must be made when calculating saturation vapor pressures in high and low pressure ranges. The buyer of both Books gets an CD and a PDF from the author

The starting point are measurements with a naturally ventilated Assmann psychrometer, described in WMO CIMO Guide no. 8 of 2008 [2] as a standard psychrometer. (Sections 4.2.2 / 4.2.6 / 4.9.7)
In Part 1, the saturated vapor pressure in [hPa] is reported over ice and then over water according to two different formulas in a table for comparison.
The partial vapor pressure PVp [hPa], the relative humidity U = R.Hum [%] and the frost point temperature tFrost [° C] are calculated from the temperatures measured on the dry and wet thermometer, whereby only the values ??U = R.Hum and tFrost [° C] are listed in the tables.
All values ??were calculated using a C program in Visual Studio 2010 on a 64-bit platform with double precision. The relative humidity and the frost point temperature were calculated for the output
with a decimal place that gives saturated vapor pressure with four decimal places. The decimal separators are represented as, (comma), for better readability be thousands separators than. (Dot) inserted.

Psychrometer table according Assmann