Device description, 7 temperature classes – KROHNE OPTITEMP TCA Ex EN User Manual
Page 11
DEVICE DESCRIPTION
2
11
OPTITEMP TRA/TCA
www.krohne.com
10/2010 - 4001087001 - Ex AD OPTITEMP TRA/TCA R02 en
2.7 Temperature classes
The permitted ambient temperature range of the industrial thermometer without temperature
transmitter on the measuring insert ("head-mounted transmitter") is:
T
amb
= -40...+100°C / -40...+212°F
Due to the influence of the product temperature, no fixed temperature class is assigned to
industrial thermometers. The temperature class of the devices is instead a function of the
following parameters:
• Present product temperature (T
M
)
• Maximum value of sensor output of connected temperature transmitter (P
O
)
• Maximum permitted temperature at the process connection of the measuring point (T
P
)
• Surface temperature of the sensor (T
O
)
The classification for the respective model is outlined in the following subchapters.
DANGER!
If you are using an industrial thermometer with head-mounted transmitter, refer to the Ex-
documentation of the temperature transmitter for the permitted maximum values for the
ambient temperature.
WARNING!
The maximum permitted product temperatures and process connection temperatures in the
tables of the following subchapters are only valid if you observe the following points:
•
The industrial thermometer has been installed in accordance with the assembly instructions
in these supplementary Ex instructions and the manual.
•
There is no additional thermal radiation at the measuring point (solar radiation, adjacent
equipment) which could heat up the industrial thermometer causing the maximum permitted
ambient temperature to be exceeded.
•
There is no additional convection from the container wall or adjacent pipes which could heat
up the industrial thermometer and cause the maximum permitted ambient temperature to be
exceeded.
•
The connection head is adequately ventilated.
•
All insulation measures only include the pipes, never the components of the industrial
thermometer.
.book Page 11 Friday, November 19, 2010 2:23 PM