MECHANICAL HVAC CONSULTING ENGINEERING.                                              DESIGN & INSPECTION: Water, Cooling, Piping, Heating, Ventilation, Air Conditioning, Automatic Control.              Slide Rule Engineering Design      

Decimal Point Slide Rule Calculator IWA1633 & 1638.  

 P-Phone Control AB

   PeriProx Control Solutions.


WERN INTER AB started 1963 in Sweden as the HVAC consulting engineering company         

Wern Inter VVS AB. It was founded by Carl R. Wern, a Registered Professional Mechanical Engineer in the state of Michigan, USA. Carl´s brother George joined in 1964 the company. 

Its present name Wern Inter AB was registered 1984.

The company has been engaged in,

Mechanical HVAC Engineering design, Control and Inspections for

 Apartment, Hotel, Shopping, Office and Recreational buildings etc

- Swedish Embassy buildings in Europe, Africa, Asia and North America

Slide rule and calculator design

- Slide rule design awarded with gold medal to the Wern brothers

- Slide rule calculator design and production for various clients


- Touch control for lighting installations patented in 1972

- Patent licence  for picture telephony on an ordinary subscriber line, sold 1976 to Ericsson.

Wern Inter AB  HVAC engineering service was closed down year 2000.

P-Phone Control AB

The company (PPC) was founded 1992 by Carl together with his brother George in a joint

venture agreement with their brother Lars who is a registered European Patent Attorney.

PPC is specialized in proximity sensing R&D starting from a sensor device patented 1972 by

the Wern brothers in its first digital version following analog versions inspired by the Serbian -

American inventor Nikola Tesla. The first patent of interest to mention was registered 1928 in

the USA by the Soviet inventor Léon Theremin. He developed an electronic musical instrument controlled without physical contact.

The Wern brothers proximity sensor was first used in lighting installations for touch control and

thereafter in art museums as invisible shields preventing exhibited objects from being touched.   

Today called PeriProx, the technology has been shown applicable for providing enhanced security 

in 2000 to a Saab car and in 2009 to a Scania truck. Its usefulness for precise proximity sensing  was shown in 2010 by Ericsson´s Connected Tree at Barcelona, Hannover and LasVegas international fairs followed by a permanent exhibition at Ericsson Studio in Kista and by a PeriProx patent in 2012 on a monitoring system for prevention against natural as well as man-made disasters.

In possession today of some patents originally filed worldwide by Scania, we want to

offer interested companies freedom to use the PeriProx technology with these patents for

developing proprietary artificial intelligence (Al) controlled proximity sensors providing

vehicles and others objects with invisible shields tailored to their periphery.

Read more below about PPC offer and historic in www.periprox.com.

Slide Rule Design

System Wern Slide Rule IWA 1633 & 1638. 

Gold medal award at the International Exhibition in Brussels 1966. http://americanhistory.si.edu/collections/search/object/nmah_1811360

National Museum of American History: System Wern ABC Circular Slide Rule.

Slide Rule Reference 

Oughtred Society, Roseville, California. USA.                      www.oughtred.org

International Slide Rule Musum, Denver Colorado, USA.    www.sliderulemuseum.com

National Museum of American History. http://americanhistory.si.edu/collections/object-groups/slide-rules

Wikipedia.                                              https://en.wikipedia.org/wiki/Slide_rule


                                           IWA 1633

Manual 1     Manual 2

IWA 1638

Note:  IWA1638. Pat.Pend. has a black washer in the slide rule center with Manual 1 and Manual 2/Except Example #28 & #29.

           IWA1638. Patended has a red washer in the slide rule center with Manual 2.

  Manual     Manual 1    Manual 2     

          1966.IWA1633                   DYNAMIC ART IWA1638                  2016.IWA1638

Slide rules manufactured by IWA Rechenshieberfabrik, W. Germany.


Special calculators                 

Design layout made by WERN INTER AB for some of our Clients.

IWA07133.  Air Duct Calculator        SI75.   Conversion Factors                kv81.  Valve Factor

1972. Metric System. 170x240 mm               1975. Technical system. 90x120 mm               1981.Water, Steam & Air. 90 x 120 mm

Manufactured by IWA, W. Germany.              Manufactured by INPLASTOR,  Sweden.        Manufactured by INPLASTOR, Sweden.

Draftsman triangle   SI-GUIDE  NavigationRuler   EO70.EconomicOrderSize

HVAC Mechanical Prototype Calculators

Water - Heating - Ventilation.  Prototypes to be shown later.


MECHANICAL ENGINEERING DESIGN PROJECTS                                

Åhléns City 1963.

Wern Inter AB - Mechanical Engineering Projects 1963-2000 - HVAC design (to be added soon)   


Conversion Factors IWA1638

Air Duct friction                 


Energi-miljo-SwedishTidskrift        HVAC VVS - Swedish Museum in Sweden       ASHRAE SOCIETY 

CRW Background

1946. Hermods Correspondence Institute, Malmö: Mathematics, Building Design Construction, etc.

1949. Stockholm Technical Institute, Sweden: Swedish HVAC Engineering Degree.

1960. Registered Professional Engineer in Michigan, USA.     

1960. ASHRAE Life Membership. 

1963.HVAC Technical Asociation in Sweden - Membership

1983. Registered Professional Engineer in Minnesota, USA.

1994. Swedish Institute for Technical Approval in Construction: Function Control/Ventilation.

Stockholm, Sweden

Copyright Carl R. Wern