16  266CRH / 266CRT, 266CSH / 266CST MULTIVARIABLE PRESSURE TRANSMITTER  |  OI/266CXX/MODBUS-EN REV. A   
 
6  Installation 
Mounting 
 
 
Before installing the pressure transmitter, check whether the 
device design meets the requirements of the measuring point 
from a measurement technology and safety specifications point 
of view. 
 
This applies in respect of the: 
• Measuring range 
• Overload resistance 
• Temperature 
• Explosion protection 
• Operating voltage 
 
The suitability of the materials must be checked as regards their 
resistance to the media. 
This applies in respect of the: 
• Gasket 
•  Process connection, separating diaphragm, etc. 
 
In addition, the relevant directives, regulations, standards, and 
accident prevention regulations must be observed (e. g., 
EN 61140, EN 61010, IEC 60364, EN 60079-14, DIN 19216, 
VDI/VDE 3511 Bl.5, etc.). 
 
Measurement accuracy is largely dependent on correct 
installation of the transmitter and, if applicable, the associated 
impulse line(s). 
 
As far as possible, the measuring setup should be free from 
critical ambient conditions such as large variations in 
temperature, vibrations, or shocks. 
 
Note 
If unfavorable ambient conditions cannot be avoided for reasons 
relating to building structure, measurement technology, or other 
issues, the measurement quality may be affected. 
 
If a remote seal with capillary tube is installed on the 
transmitter, the additional operating instructions for remote 
seals and the related data sheets must be observed. 
 
 
 
 
 
IP rating 
The housing of the 266CRH / 266CRT, 266CSH / 266CST 
pressure transmitters satisfies the requirements of IP degree of 
protection IP 66 / IP 67 (NEMA 4X) in accordance with IEC 60529. 
 
The first digit indicates the protection of the integrated 
electronics against penetration of foreign objects, including 
dust. 
•  The digit ‘6’ means that the housing is dust tight  
(for example dust cannot penetrate).  
 
The second digit indicates the protection of the integrated 
electronics against the penetration of water. 
•  The digit ‘6’ means that the housing is watertight and can 
even withstand a strong water jet under the specified 
conditions. 
•  The digit ‘7’ means that the housing is watertight and can be 
temporarily immersed at a specified pressure and for a 
specific time, without water penetrating. 
 
 
Factory settings 
 
The pressure transmitter is factory configured according to the 
customer’s order specifications. 
Under normal conditions no additional settings are required. 
The typical configuration includes: 
•  Number of the measuring point tag 
• Calibrated span 
•  Configuration of the flow or liquid level calculation 
•  Configuration of the LCD display